GCN and Zone 2

 

Two posts ago, I talked about my attempts to come up with a training plan to reverse the decrease in cycling speed I have been experiencing. In that post I said, with regards to my plan to cut back on long, slow rides in favor of faster, shorter rides, that I had the following concern: "... my slow training in 2021 was based on some of the most respected and widely accepted training advice in the cycling community, the value of Zone 2 training. Even to myself, increasing my speed seemed more like flailing than an upgrade." To address that concern, I am continuing to read and think about Zone 2 training.

[Brief Tutorial: The Intensity (e.g. how fast it is) of a bicycle ride is is usually described in terms of Training Zones, with Zone 1 being the easiest (slowest) ride and Zone 7 being the hardest (fastest.)]

Global Cycling Network (GCN) is an online cycling magazine which I have come to really like. When I have a question about cycling, they often have an answer that is comprehensive, clear, and plausible. I recently stumbled across a four part series they did on Zone 2 training that I found very helpful.

Part 1 was an interview with Iñigo San Millán, PhD, of University of Colorado School of Medicine. He is an exercise scientist and coach to a number of Tour de France riders, including the current wunderkind of cycling, Tadej Pogačar. I did a bit of research on his credentials and I was impressed. He talked about how the slow twitch muscle fibers which are developed by Zone 2 training are critical for supporting the fast twitch muscle fibers used during high intensity racing because they metabolize the lactate generated by those fast twitch muscle fibers. His bottom line recommendation is the same advice I have been reading from several other sources, that the optimum training schedule consists of 80% Zone 2 training and 20% training at higher intensity targeted to one's goals.

Part 2, which was narrated by GCN reporter Simon Richardson, was about how to identify your Zone 2. According to him,  heart rate and power are not good ways to do this, though they are useful for tracking zones once calibrated. Simon's definition of top of Zone 2, confirmed by Dr. Millán, is the point where fat metabolism plateaus. This is determined by measuring O₂ consumption and CO₂ generation during exercise.

The top of Zone 2 is also where blood lactate goes from flat to increasing. There is second level of lactate that is considered significant which is identified by a further increase in the slope of the lactate vs exercise graph and it is useful to describe these two lactate levels together.  As noted above, the first increase in lactate defines the upper boundary of Zone 2. The further increase in the slope of the line defines the upper boundary of Zone 4. Unfortunately, the terminology used for these two levels of lactate is inconsistent and therefore confusing. Even within this series of four videos, different terminologies are used at different times. Some of the names used for the lactate level at the top of Zone 2 are Lactate Threshold (LT), the first Lactate Threshold (LT1) or the Aerobic Lactate Threshold (AeT.)  Similarly names used for the lactate level at the top of Zone 4 are the Lactate Turn Point (LTP), Lactate Threshold 2 (LT2) or the Anaerobic Lactate Threshold (AnT or simply AT.) 

Both lactate and respiratory gas measurements require a laboratory. In the absence of a laboratory, breathing tests are the best measure according to Richardson. The top of Zone 2 where conversation is forced but possible and where one can breathe entirely through the nose. An alternative is to use Relative Perceived Exertion (RPE.) On the standard 6-20 RPE scale, the top of Zone 2 is 12.

Part 3 was both narrated by and focused on GCN reporter Manon Lloyd. (The picture at the top of the post is of Lloyd.) Lloyd had been an elite cyclist earlier in her life, but, in her words, she was "ten times as unfit" now had she had been back then. The premise of this and the next video is that she is going to use herself as a test case for the benefits of Zone 2 training. Besides the results of the experiment, we also get to see a state of the art version of how such an experiment is done.

Lloyd worked with the Human Performance Laboratory of the University of Bath in order to determine her fitness level at the beginning of the test and to establish her heart rate and power output at Zone 2. To do that, her blood lactate and breath O₂/CO₂ were measured every few minutes while she rode an exercise bike at increasing speeds:

Lloyd then met with her former coach to develop a six week Zone 2 training plan.

Part 4 reported the results of that training plan. The same tests were repeated and the results were compared to the results at the beginning of the test. Lloyd saw a significant improvement not only at the lower intensities around Zone 2 but at the high intensity zones as well:

I will go through these results line by line. LT (W) is how much power Lloyd could generate at her lactate threshold. At the beginning of the experiment, it was 140 watts. Six weeks later it was 160 watts. My estimate is this roughly corresponds to an increase in speed on a flat, windless road from 17 mph to 18 mph. LTP (W) (AP on the graph above) is the same value for the Lactate Turn Point and roughly corresponds to an increase in speed from 18 to 19 mph. It can be hard to accurately identify the points on the graph where these two increases in slope occur, and so sometimes these blood lactate levels are identified as absolute concentrations, e.g. 2 mM and 4 mM. The power levels at these two lactate concentrations is shown on lines 3 and 4.

The remaining four lines refer to VO₂peak. This is the more cautious, scientific version of the more commonly used VO₂max and for the purposes of this post, we can consider them to be the same thing. This is the maximum amount of oxygen an athlete can use and occurs near or at their highest level of exercise. Line 5 gives the ratio between the power Lloyd output at LT (the top of Zone 2) and her maximum power output. Line 6 shows the same thing for her power at LTP. Both of these increased during Lloyd's six weeks of training. The seventh line is the absolute value of VO₂peak itself. This increased by about 7% over the six weeks. The values both before and after training would be considered good but not elite. It might be expected that Lloyd could further increase this value with additional training. Finally, in line 8 we see that the maximum amount of power Lloyd could produce increase by about 12% over the six weeks. 

It is unsurprising that the Power Lloyd could generate at LT increased since that is the intensity at which she trained, but it is perhaps less intuitive that her power at LTP and at maximum power (power at VO₂peak) increased as well since these are levels of Intensity much higher than that at which she had trained. This is consistent with an article I posted about in 2021, a case study of an athlete who was having trouble increasing their VO₂max who, when he switched from the Zone 5 and Zone 6 workouts typically prescribed for increasing VO₂max to a three year program heavy on Zone 2, experienced a dramatic increase in his VO₂max.

Besides this four part series, I found some related articles from GCN, one on Sweet Spot training, one on Training Zone definitions, and one on Overtraining. The video on Sweet Spot training was the least useful, but I was pleased that the narrator, reporter Simon Richardson, suggested the same thing I had, that perhaps Sweet Spot training (training at the top of Zone 3 and the bottom of Zone 4) would be useful to cyclists whose time for training is limited. I noted that Dr. Iñigo San Millán was not featured in this video and suspect he would not have agreed. I found the use of training zones in the four part series to be inconsistent, so when I came across a video just about training zones, I had to watch it. The definition of Zones in this video was almost exactly the same as that used by Coach Hughes, which was comforting. The one difference was that Coach Hughes recommends Zone 6 for increasing VO₂max and GCN recommends Zone 5, claiming that Zone 6 is used to anaerobic capacity. That video credited Andrew Coggan as the developer of this 7-zone system, a fun fact I found of interest. Most significant was a third video which was again hosted by Richardson. This video consisted almost entirely of an interview of Dr. Iñigo San Millán. The topic of this video was overtraining. The symptoms of overtraining described in this video described how I am feeling right now with terrifying precision.

How did this series affect my training? As I note frequently, I try to limit the advice I take to one coach, Coach John Hughes, but Coach Hughes' advice is somewhat inconsistent when it comes to the value of training in Zone 2 and Zone 3. Thus, that balance is something I need to decide for myself. I go back and forth on this, and this series of videos pushed me back towards more Zone 2 training. However, the biggest impact on my training came from one of the three extra videos, the one on overtraining. Not that this video told me anything I hadn't heard before and it is not as if I were not wondering if I was suffering from overtraining even before I watched it, rather, it was more like perfect timing. I was ready to hear this message, especially because it came from a prestigious and credible coach and scientist. I let this message sink in, I watched it a second time, and then I decided to take a week off from training. This is not a violation of my determination to focus on Coach Hughes, Coach Hughes also recommends taking a week off from training at appropriate times. If anything, I had been taking off fewer weeks than Coach Hughes recommends. Thus, this video simply focused my attention on something I should have been doing anyway.

Some final, miscellaneous things I learned from this series of videos:

• Lloyd's coach noted that it is important that Zone 2 training rides be long in order to generate the stimulus needed to increased fitness. I have noted in the past that Polarized Training may be more about the lower end of that polarization (Zone 2) than the higher end. Similarly, I am getting the impression that it is the length of Zone 2 rides that makes them valuable.
• Decoupling is the well known phenomenon where heart rate increases at the end of a long ride with no increase in effort. For Zone 2 training, how do you handle that? GCN says when heart rate trends up, you should slow down to bring your heart rate back down. Coach Hughes disagrees. He says to maintain your speed and ignore your heart rate. I haven't decided what I think about this yet, but it is good hear the other side of the story.
• Manon Lloyd complained (as I have) that it is hard not to drift from Zone 2 up into Zone 3 when climbing hills. In the first place, it is comforting for me to realize I am not the only person struggling with this. In the second place, Lloyd's coach said 30 seconds in Zone 3 does not ruin a Zone 2 ride, so that within reason, hills can be ignored. Elsewhere in the series, however, it is noted that it is important to ride at a steady pace because it takes about 5 minutes to feel the intensity of a pace, so such drifts upwards should be kept short. GNC claims that if you do exceed Zone 2 for too long, it takes about 30 minutes to get back to the physiology of Zone 2 where you can obtain its benefits.

Implicit in this post is that I am reexamining my training schedule yet again. I plan to talk about that in more detail in a post in the near future. Stay tuned.

Update on the Banister Model

I track my training to help me train enough to reach my goals while not training so much as to result in overtraining, long term exhaustion, and failure. Listening to my body is my best defense against that, but I find it useful to compare what my body is telling me to how much riding I have been doing to help me decide what rides to do next. The tricky bit is what "how much riding I have been doing" means. It's easy to track how many minutes I spend riding (Volume) and it seems reasonable that, all things being equal, a two hour ride will make me twice as fit (Fitness) and twice as tired (Fatigue) as a one hour ride but how fast I ride (Intensity) during those minutes also affects my levels of Fitness and Fatigue. In that case, however, the question of "By how much?" is not so easily answered. The units of Fitness and Fatigue are arbitrary, so as long as I track only minutes, I only need to worry about relative values, absolute values don't matter.  But when I add how hard a ride was (how fast, how hilly, etc., known as Intensity) I am forced to ask how much an increase of speed of 1 miles per hour (for example) affects my Fitness and Form compared to the effect of adding 60 minutes to the length of that ride. Additionally, not only do Fitness and Fatigue increase in response to riding but both also decrease over time when I don't ride. Finally, how to Fitness and Fatigue interact? In my opinion, the answers to these questions are not known with certainty but I also feel like I should make my best guess to their answers and do the best that I can.

One tool many cyclists use to help answer these questions is the commercial Training Peaks software package. An alternative I have been playing with is the Banister model. Thus, I was excited to stumble across this blog post:  "Implementing the Banister Impulse-Response Model in GoldenCheetah". (GoldenCheetah is an open source software package for analyzing cycling data.) In addition to the contents of the blog post itself, the author cites a scholarly paper by Dave Clarke and Phil Skiba which contains a tutorial and review of the Banister model. The reasons I was excited was the confidence boost I got from the fact that someone besides me is interested in the Banister model and the hope that I could learn from their experiences. One big thing I learned was that the community of scientists, coaches, and athletes using the Banister model is focused on customizing the parameters of that model to each individual athlete, something I blogged about doing myself, though that is still a work in progress. This is a feature that Training Peaks does not have, so someone like me who is using the Banister model without customization is no worse off than one of the many Training Peaks users. Also, the Clarke and Skiba paper suggests that the model is not very sensitive to small changes in the parameters suggesting that customization might not be so important.

I have been using the Banister model for more than two years now and it certainly has not been perfect at predicting the impact of my training on my cycling ability, but I have the impression that it does give me hints that are helpful in combination with what my body tells me in optimizing my training. I hope to post more about this in the future as I learn more. So why post about it now?

Five months ago, I blogged that coming up with an equation for calculating my ride Load was a work in progress.The Banister model includes a formula for calculating Load. Load is a combination of Volume, the duration of a ride in minutes and Intensity (how "hard" a ride is.) They are linked as follows:

Load = Volume x Intensity. 

One way to measure intensity uses Heart Rate and there are many different formulas of calculating Intensity from Heart Rate.  I have compared several of these formulas and a number of them seemed fine. Given that, I decided to use the method proposed by Banister, thinking there might be some value in using the Intensity calculation and the accumulated Form, Fatigue, and Fitness model from the same author.

One disadvantage of the Banister method for calculating Load is that is more more complicated than it needs to be, in my opinion. That said, this complexity doesn't seem to make its estimates any worse and that once I coded this method into the spreadsheet I use to track my training, it didn't make tracking my training any harder, so this is what I am using for now to convert the heart rate I measure to Intensity. 

In an attempt to make Banister's method easier to understand, I am going to break it up into pieces. The first thing to know is that the Banister method is based on Heart Rate Reserve (HRR), the difference between the lowest heart rate an athlete exhibits, the resting heart rate, and the highest heart rate they can attain:

HRR = Heart Rate Reserve = (Maximum Heart Rate - Resting Heart Rate)

Intensity is related to how much of that reserve an athlete uses during a particular level of exercise, what I call Fractional Heart Rate Reserve (FHR):

FHR =  (Exercising Heart Rate - Resting Heart Rate) / (Maximum Heart Rate - Resting Heart Rate)

Finally, FHR is used to calculate Intensity:

Intensity = FHR x 0.64 x e^{(1.92 x FHR)}

0.64 and 1.92 are constants that Banister provides.

I went back and recalculated all my Intensity measurements since I obtained my TranyaG0 sports watch in 2022 and the results consistent with my subjective impressions. Problem solved!

How much of a difference does it make to my training if I track Load instead of just tracking Minutes like most coaches recommend? Not a lot, but some. The way I measure that difference is the ratio of Load to Minutes. If Load made no difference, that ratio would be 1. Since I resumed tracking my heart rate in July of 2022, that ratio (averaged over a week) has gone from a high of 1.5 to a low of 0.4. The 0.4 and similar low ratios occur during weeks when most or all of my rides are Zone 1 recovery rides on my trainer and thus those low values were expected. Perhaps Load is more useful for the weeks where Load is greater than Minutes. As noted on the graph above, it is fairly common for the Load to be 1.25 times as large as Minutes. I have noted in the past that I should try to ride at least 300 minutes a week but if I routinely ride much more than 400 minutes a week I risk buildup of Fatigue. Consider a week when I am feeling strong where I might ride for 400 minutes. I might feel like that was on the edge but not excessive. However, it would not be uncommon that the same week might have a Load score of 500 (Load/Minutes=1.25) making it something worth noting.

After the Birthday Ride

 

My last post, which was about my 75th Birthday Ride, was one of the posts that was the most fun to write because it was about a high point in my life. However, lurking in the background was a darker theme, one that I have been blogging about more and more: I am getting old, and getting old comes with limitations. Although neither a prediction nor a promise, I doubt I will ever do another birthday ride. One reason is that my 75th Birthday Ride was so special that future Birthday Rides would suffer by comparison. The more important reason is that part of what made my 75th Birthday Ride so special is that it was a challenge, a challenge that was quite difficult for me to meet, and each year that challenge will get greater. Obviously, adding 1 mile to the length of the ride each year is not a big deal (at least for a while) but each year I am also getting a year older and at this point in my life that is significant. What was a fun and healthy challenge in 2024 will quickly turn into an inappropriate risk as the years progress.

Given that, what have I been doing since the birthday ride? Have I been doing any riding at all? Is there any plan to that riding? Yes, I have been riding and yes, there is a plan. For the first four weeks after my birthday ride I was feeling very tired, which is as expected. To recover, I rode three to four moderate length (1½ to 2 hour) rides at low intensity (Zone 2 on a scale of 1 to 7) a week. By the end of those four weeks, I started feeling less tired so started upping the intensity of those rides from pure Zone 2 rides to rides that were about a 50:50 mixture of Zone 2 and Zone 3. Why did I make that change in particular? The answer to the question is the topic of the remainder of this post. As is shown in the graph at the top of this post, my ride speed has been dropping for the past several years and for the remainder of 2024 I am going to focus my training on trying to increase that ride speed.

What does it mean to say that "my ride speed has been dropping"? The usual way this would be determined, the way recommended by most coaches, is by riding periodic time trials, a ride on a fixed course ridden as fast as possible. I don't do that. Another way, which I would argue is every bit as good, is to do that ride not as fast as possible, but at a fixed heart rate. The name for such a ride is a MAF test, and between 2012 and 2017 I rode a total of 478 MAF tests. Once I moved to California, I was unable to ride MAF tests and eventually hit upon the idea of averaging my speed on a set of rides I refer to as the Alpine-Like rides. In theory, this is not nearly as reliable as a time trial or a MAF test, but in practice it turned out to be good enough to be useful, and the message of those 341 rides (displayed in the graph at the top of the post) is that I am getting slower. Since I move to California in 2017, my speed on these rides has gone up and down but overall, has decreased by about 1.6 miles per hour since the move. I have done this estimation in a variety of different ways, sometimes comparing average speed, sometimes comparing maximum speeds, and the overall decrease is always about 1.6 miles per hour.

Why did my speed on Alpine-Like rides decreased by 1.6 miles per hour between 2017 and 2024? There are many possible explanations. The obvious one, foreshadowed at the beginning of this post, is that it is due to the fact that I am getting older. Another explanation might start with the observation that I have not gotten slower at a slow, steady rate, but rather my speed has gone up and down. Most dramatically, my average speed increased by about 0.4 miles per hour between the middle of 2017 and the beginning of 2020, and then decreased by about 2 miles per hour thereafter (again, with ups and downs.) Perhaps I made different training decisions at different times and that it is the training decisions I have made since 2020 that are responsible for my current low speed. There are other explanations, of course, and these explanations are not, in general, mutually exclusive; poor training decisions combined with the effects of aging could have worked together to produce my current sad state. It occurred to me that deliberately focusing my training for the rest of 2024 on attempting to increase my speed on my Alpine-Like rides might have a number of benefits. First, it would give my training a focus, it would make it more fun and interesting. Second, I might learn something. To the extent my slowness is due to age, I should not be able to train my way out of it. To the extent it is due to training, then I should. Finally, if I do succeed in increasing my speed, that should benefit both my health and my ability to do more challenging rides in the future, perhaps even with my faster friends.

How would I change my training to focus it on speed? My guess is that well in excess of 90% the massive amount that is published about bicycling claims to provide answers to that question. This literature, besides being massive, is confusing, complex, and contradictory. At some point I decided to bypass all that by taking the advice of only one coach and and the coach I selected was Coach John Hughes. One of his eBooks that I use a lot is "Intensity Training for Cyclists". Hughes suggests that, to build speed, a rider like me might spend something like 20% of my training time in Zone 1, 40% in Zone 2, 30% in Zone 3, and 10% in Zone 6. 

I confess that Coach Hughes was not my first stop in pursuit of speed. I first came up with a training plan on my own. It was based on my history, my intuition, and listening to my body. One additional explanation for my falling speed, and one with particular relevance to my Alpine-Like rides, is that in 2021 I deliberately slowed my speed on those rides as a response to falling performance. So the first part of my plan was to reverse that decision. It even occurred to me that my recovery might be instantaneous - I might be riding slower just because I decided to ride slower. I quickly found out that was not the case. Even when I tried my best, my speeds on my Alpine-Like rides, both my top speeds and my average speeds, were much lower than back when I first moved to California.

My second thought was that if I maintained my higher speeds on my Alpine-like rides, I could train myself back to where I had been. There were two logical flaws with that line of thinking. The first was that from the day I arrived in California, I was achieving higher speeds on my Alpine-Like rides than I am now despite having arrived with a training history that was extremely weak. I had not trained my way into those higher speeds and so I should not have to train my way back into them. The second logical flaw is that my slow training in 2021 was based on some of the most respected and widely accepted training advice in the cycling community, the value of Zone 2 training. Even to myself, increasing my speed seemed more like flailing than an upgrade.

Besides increasing the speed with which I rode my Alpine-Like rides, the other change I decided to make was to try "sprint workouts" one more time. Specifically, I decided to try adding the Tamarack Sprint back to my schedule. In retrospect, my thinking on these kinds of "brisk" or "high intensity" or "sprint" workouts was extremely naive: simply dropping a ride of random intensity into my schedule was logically questionable.

So did I throw all the above ideas out when it finally occurred to me to look at what Coaches Hughes had to say? No, but I did modify them. Either by chance or because I have internalized the ideas of Coach Hughes, the training ideas I came up with on my own were not all that inconsistent with those of Coach Hughes. The main effect of looking at Coach Hughes' recommendations was to moderate my plans, to make my changes less drastic. 

One of the things I really tried to figure out this time around was the benefits that are supposed to accrue from interval training in different training zones. The Tamarack Sprint is a Zone 6 workout. Hughes is less than helpful in helping me figure out the benefits that come from Zone 6 workouts, he says somewhat cryptically that they improve "VO2 Max", but he does recommend Zone 6 workouts for riders like me, so I will keep the Tamarack Sprints in my current training plan. Besides, these rides give me an opportunity to enjoy my antique 1963 Bianchi Specialissima.

The word "speed" appears in Hughes' Intensity descriptions for two Intensities. He describes the purpose of Zone 5 workouts to "Increase Racing Speed" and the purpose of Zone 3 workouts to "Increase Cruising Speed". I'm not a racer and in any case I find it hard to do controlled Zone 5 workouts but increasing cruising speed seems like exactly what I am looking for. When I read Coach Hughes recommendations slowly and carefully I think there is more subtlety than is suggested by the above. What I think he is saying is that to increase my speed I should first do more riding in Zone 3, and then later in the Sweet Spot (an alternative Zone that is on the border of Zones 3 and 4) and only then start including workouts in Zones 4 and 5. When I say that I am riding my Alpine-Like rides faster, that translates to going from riding them almost 100% of the time in Zone 2 to some mix of Zones 2 and 3, with a little bit of Sweet Spot, Zone 4, and Zone 5 mixed in as a bonus, pretty close to what Coach Hughes recommends.

One surprising recommendation from Coach Hughes is that I should be doing more of the recovery rides on my trainer than I had planned to do. Something I struggle with is perverse incentives driven by my compulsive record keeping. Recently, my body has been quite clear in telling me not to overdo my training. What that meant is that when I choose to ride faster, I have to compensate by riding fewer minutes. However, when I project that the minutes I am going to ride in a given week may not reach the arbitrary minimum I have set for myself of 300 minutes, I am tempted to throw in an extra recovery ride just to get 30 more minutes. That logic is terrible! Every ride should have a purpose and gaming my training statistics is not a purpose. However, Coach Hughes has a recommendation for the percentage of my minutes that should be ridden as recovery rides, and the plan I had come up with on my own was well below his minimum, so I now plan to include more recovery rides in my schedule.

Another change reading Coach Hughes had on my training plans for the remainder of 2024 is to include more total minutes and more Zone 2 time in my schedule than I had planned. As noted above, my body is telling me to not overdue the total amount of my training, so if I am going to take that suggestion, I will probably need to cut back somewhere else. Thus, I am now planning fewer of the Tamarack Sprint intervals and fewer fast Alpine-Like rides that I had originally.

Some of this seems like I am giving up and just going back to what I had been doing before. That is an exaggeration. I think the characterization I made above, that I am moderating my changes, is more accurate. However, there is another point to make. If you look at the ups and the downs of my speed on the Alpine-Like rides, the trend for 2024 is quite encouraging. Thus, all things considered, while I still think it is appropriate to change the focus of my training as I am describing in this post, I now see that as a minor adjustment to a training plan that was already working fairly well rather than a major course correction. How will this work out? Stay tuned to find out.

Birthday Ride

There is a tradition in the cycling community of The Birthday Ride. Classically, the tradition is to ride your age in miles on your birthday, though there are variations. This year I turned 75. To me, this felt like a big deal: three quarters of a century! Short of living to be 100, I don't think I will ever have a more special birthday. Never in my life had I ridden a Birthday Ride but it seemed like if I ever were to do one, this should be the year.

I can't remember when it occurred to me that I should to do a birthday ride this year. I did consider a birthday ride in 2021. Back then, that ride would have been 72 miles long. What inspired this was that I was having a bad year. I had just failed to complete my training plan for the Art of Survival metric century and I thought I might be able to compensate for that failure with a Birthday Ride. Unfortunately, the same problems that kept me from preparing for the 60 mile long Art of Survival kept me from preparing for a 72 mile long Birthday Ride. I did have a plan to attempt a 75th Birthday Ride by last February because I mentioned it in a blog post. So it was probably sometime between May of 2021 and February of 2024 when I decided to attempt a 75 mile long birthday ride this July.

The Plan

I knew that completing 75 miles would be a challenge for me at my age and at my level of fitness so I focused on doing everything I could to make it possible for me to complete the ride. To that end, I decided the ride should be flat. To keep things simple, I decided to make the ride local. When I thought of rides that met those criteria, I decided that a ride along the Bay Trail was most promising. The Bay Trail is not yet complete, the current version consists of a collection of disconnected segments. There are two of these segments I ride regularly which I have named Bay Trail North and Bay Trail South. Back in 2019, I did a solo metric century in order to test my Metric a Month training plan and the route for that consisted of both of those segments as well as the city streets needed to get from one to the other. After a lot of thought, I decided that doing that for my Birthday Ride would make the ride too difficult so eliminated that option. If I were to ride only one of these segments, how would I get enough miles? In 2019, the parts of Bay Trail North and Bay Trail South with which I was familiar were similar in length. Since then, I have extended my knowledge of Bay Trail South, and, in addition to the Bay Trail itself, have explored four other high quality trails that connect with this segment of the Bay Trail: The Permanente Creek Trail, the Stephens Creek Trail, the Tomas Aquino Creek Trail, and the Guadalupe River Trail. Thus, I decided to string together a subset of these to construct a 75 mile long ride. The ride I actually did is shown in the figure at the top of the post and is discussed in more detail below.

Historically, I have favored bike rides that start and end at my house. More recently, I have been doing more rides where I put my bike on the back of my car and drive to the start point. I am working on a blog post explaining the advantages and disadvantages of each of these options but briefly, driving to the start of a ride opens up a lot of possibilities, especially now when I live in such a hilly neighborhood. For my birthday ride, I drove to the parking lot for Shoreline Lake Park which became the start and finish for the ride.

The Route

This ride took advantage of some of the wonderful cycling infrastructure provided by various governments in the San Francisco Bay Area. In addition to The Bay Trail about which I have previously blogged, I considered the four other trails listed above for inclusion into this ride. In the end, of the four other trails I considered, the ride included two: the Tomas Aquino Creek Trail, and the Guadalupe River Trail. I had ridden the full length of the Guadalupe River Trail during my metric century three weeks before and based on that experience decided to include only the first 6.7 miles of that trail in my Birthday ride. In earlier rides, I had ridden the first part of the Tomas Aquino Trail but had never ridden its full length, so took the opportunity of my Birthday Ride to do so. In the end, these two trails added 24 miles to the ride

The current version of the San Francisco Bay Trail has a somewhat complicated topography: it has gaps, it has branches, it merges with itself, and it has alternative routes. Sometimes it not obvious if one is on the Bay Trail or not and sometimes what the official map shows does not match what is on the ground. Given all that and knowing this section of the Bay Trail as well as I do, I decided that I would declare that everything that wasn't explicitly on one of the other two trails to be on the Bay Trail. Given that assumption, the Bay Trail accounted for 51 miles of the ride. 

Final statistic: If I leave off all the side trails and loops, a ride on the Bay Trail South segment from Cooley Landing to Alviso and back is 34 miles. A similar ride on the Bay Trail North segment from the Belmont Sport Complex through the Coyote Point Recreation Area and back is 20 miles.

The Training

2024 was something of a comeback year for my cycling. As noted above, 2011 was a bad year for my cycling. At the time, I blamed that bad year on my move from a relatively flat neighborhood to a very hilly one, though over time I have become somewhat skeptical of that idea. 2022 was a good year. In 2023, back problems interfered with my cycling, making that a bad year. On February 1, 2024, my level of fitness had reached to a very low level and it was from that low point that began a training program to prepare myself to ride the 2024 Art of Survival Metric Century at the end of May. By then, I had also decided to attempt a Birthday Ride, but did not have a clear plan for training for it. As I trained for and then completed The Art of Survival, I decided to use the Metric Century a Month training plan I had developed back in 2019 to prepare for my Birthday Ride. This plan was not a perfect fit in that the Birthday Ride was to be 75 miles long, longer than the 62 mile long ride for which the plan was developed, but I decided to ignore that mismatch. One implication of that plan is that I would need to ride an additional Metric Century between Art of Survival and the Birthday ride; the monthly Metric Century is an essential part of this training plan and there was two months between those two rides. I decided to do a solo metric century at the end of June to accomplish that requirement.

The Metric Century a Month Training Plan assumes a metric century ride every four weeks. This is somewhat unrealistic, metric century rides are not distributed that regularly across the calendar, and in response to that, it can be adjusted a bit by adding a week or two by repeating week 2 of the schedule, so I had planned to ride one four week schedule and one five week schedule, giving me some flexibility as to when to do my solo metric century; I could do it June 22 or June 29. As seems to always happen for me, my training schedule got disrupted so I was unable to ride my solo metric century on either of those weekends.  How did that happen?

The first four week block of the Metric a Month schedule went according to plan with the exception of one apparently minor change: the first week of that block, the recovery week, contained a few more miles than it should have. That was the result of me being undisciplined. I was feeling good that week and rode 33 miles on a day I was scheduled to ride 17. In retrospect, that may have been more of a mistake than I realized. But it was at the end of this block that my training plan really fell apart. The reasons for that were threefold:

1. I had a bunch of extra, unexpected babysitting to do. (Babysitting takes precedence over even a 75th birthday ride.)
2. There was a heatwave which made it unwise for a 75 year old to ride on some days.
3. The Art of Survival left me more tired than I expected and it took me longer than I expected to recover from that to a point where I felt I could ride a metric century.

These three things are not mutually exclusive, of course. The extra babysitting could have generated fatigue that contributed to my slow recovery, for example. The other thing that could have contributed to that slow recovery was the extra riding four weeks earlier, mentioned above. The result of all this is that I failed to ride a metric century four weeks after The Art of Survival and then again at five weeks. At that point, I was extremely discouraged, I was 90% convinced that I was not going to be able to do the Birthday Ride. What changed that was that one week later, six weeks after the Art of Survival and three weeks before my 75th birthday, I woke up one morning feeling pretty good. I decided to drive out to Shoreline Lake with no preconceptions to do a little scouting and to see just how good I felt. In the end, I rode 61 miles without undue fatigue. At this point, the Birthday Ride was back on, but how to train with three weeks to go? The following week, I rode the first, easy week of my Metric a Month schedule - which is what I should have ridden after the Art of Survival but didn't. Although I hadn't found the 61 mile ride tiring at the time, I felt quite tired during that week - I was having the same trouble with slow recovery as I had had during the previous five weeks. So instead of moving to a harder schedule for the second week, I rode the easy week of that schedule again. As I listened to my body, I had the feeling I was finally recovering from my solo metric century just in time for my Birthday Ride, suggesting this adjustment was a good one.

How Did It Go?

The day was magnificent both as a bike ride and as a birthday celebration. My son Michael decided to join me on the ride. We began by riding 45 miles southwest from Shoreline Park and back before stopping at the delightful restaurant in the park for lunch. My sister and brother-in-law. my son Matthew and his son Graham (age 2), and Michael's wife Robynn and their two children Julia (age 8) and Elliott (age 6) met us there and we had a delightful lunch, including a slice of birthday cake complete with a 75th birthday decoration provided by my cousin Rebecca. Michael and I then did a 3 mile loop around Shoreline Lake with Julia and Elliott so they could be participants in the ride. They are beginning cyclists and so found that loop just enough of a challenge to be exciting. Then Michael and I rode northeast to just past Cooley Landing and back which brought us to 69.7 miles total. We finished things off with two more laps 

around the 3 mile lake loop to reach our goal of 75 miles.

I felt comfortable and strong during almost all of the ride, it was only at the very end that I began to feel some fatigue. However, by the time I got home and took a shower, I was exhausted, a feeling that lasted through the following day. I am definitely riding a recovery schedule for the week after this ride!

My goal for this ride was that it should feel special. During the weeks before the ride when I was feeling like it might not happen, everyone I talked with urged me to scale back my ambitions rather than abandon the ride entirely. These suggestions ranged from riding 75 kilometers (47 miles) to making the visually minor adjustment of reducing it from 75 miles to 7.5 miles. None of these would have felt special. This 75 mile long ride was the longest ride I have done in over 10 years, the longest I have done since moving to California. That's special! Between the challenge of the ride, the delightful lunch, and the participation of my family, I cannot think of a better way to recognize this very special birthday.

Moderate vs. Vigorous Exercise

 

I have two reasons for riding my bike on a regular schedule. The less important reason is to be ready for long distance fun rides with my friends. The more important reason is for my health. What is the advice of the Medical Community for how much aerobic exercise (e.g. bicycle riding) I should do? Pretty universally, the Medical Community recommends a minimum of 150 minutes a week of "Moderate" exercise or 75 minutes a week of "Vigorous" exercise. These can be mixed and matched, e.g. one can meet that recommendation with 50 minutes of Vigorous exercise and 50 minutes of Moderate Exercise. This is a minimum recommendation. The ideal is twice that, 300 minutes a week of Moderate Exercise or 150 minutes a week of Vigorous Exercise in any combination. The key issue for me is the definition of Moderate and Vigorous Exercise. Originally, I kept things simple by assuming that all my cycling constituted Moderate Exercise. However, after looking at the guidance provided by various branches of the medical community as to what constituted Moderate and Vigorous, I felt like that was a very conservative assumption, that much of my cycling was at the Vigorous level. About 2012 I started collecting various heart rate zone systems. One of them was one that defined Moderate and Vigorous exercise in terms of heart rate, and it came from a source I trusted, the Mayo Clinic. That system said that Moderate Exercise is 50 to 70% Maximum Heart Rate and that Vigorous Exercise is 70 to 85% Maximum Heart Rate. If I use an estimate of 180 for my Maximum Heart Rate, the Moderate exercise zone goes from 90 to 125 beats per minute and the Vigorous from 126 to 153 beats per minute. Because so much of my riding was at a heart rate in the Vigorous zone, and because my recovery rides, easy rides from a training perspective, qualified as Moderate Exercise, I found it easy to reach the recommended amount of aerobic exercise. Recently, I went back to the Mayo website to confirm some aspects of this classification and I found that they had revised their recommendations; they now use a different set of  zone definitions. Using that new system and my maximum heart rate of 180 beats per minute results in Moderate exercise being 125 to 147 bpm and Vigorous being 147 to 164 bpm. This is a huge difference. This means not only are my Recovery Rides no longer Moderate Exercise and thus no longer count towards my 300 minutes but also that a significant fraction of my Zone 2 rides don't count either. Further, very little of my riding qualifies as Vigorous. To be honest, even before seeing these new recommendations I had been worrying that the old set of zones seemed a bit too easy. However, the second set of zones definitely seem much too hard. Not only would they make it difficult to impossible for me to meet the health guidelines, I would have to deviate significantly from the carfully thought out and extensively tested training plans I am currently following to even try to do so.

What accounts for the enormous change in the guidance the Mayo Clinic offers to Americans trying to figure out how best to exercise? This change is the result of Mayo switching from Percent Maximum Heart Rate to Percent Heart Rate Reserve for calculating the boundaries of of Moderate and Vigorous exercise. What is heart rate reserve? It is the difference between resting heart rate and maximum heart rate. For me, my maximum heart rate is 180 bpm and my resting heart rate is 70 bpm so my heart rate reserve is 110 bpm. The way the new method works is that heart rate reserve is multiplied by appropriate percentages and then the resting heart rate is added back. Using the percentages in the latest recommendations from Mayo, Moderate and Vigorous exercise are 50% to 70% and 70% to 85%, respectively, then the boundaries for the new system are:

(50% x 110) + 70 = 125 bpm
(70% x 110) + 70 = 147 bpm
(85% x 110) + 70 = 164 bpm.

But where did Mayo get these percentages? Why should they be the same as for the old Maximum Heart Rate system? Spoiler alert: I think the whole thing was the result of a misunderstanding by the Mayo Clinic and should be ignored. Who am I to accuse the Mayo Clinic of "a misunderstanding" especially after describing Mayo in this very post as a source I trust? Clearly I have to defend that charge, and in addition, I have to accept responsibility for my part in this confusion. I do consider the Mayo Clinic one of the most prestigious and trustworthy institutions in the medical establishment. The problem is, the medical establishment is really good at some things and less good at others, nutrition and exercise being areas in which the medical community is less good. My mistake was thinking that the Mayo Clinic would be an exception to these limitations, I put more trust in them with regards to exercise than I should have. The first thing that should have given me pause is their suggestion of using an age-determined estimate for maximum heart rate. In their old recommendations, they suggested the classic estimator of:

Maximum Heart Rate = 220 - Age

For me, that would be 220 - 74 = 146 bpm. Given that I routinely hit heart rates of over 160 bpm and that, about a year and a half ago, I reached a heart rate of 176 bpm, this is absurd. For their new recommendation, they suggest a more modern formula: 

Maximum Heart Rate = 208 - (0.7 x Age)

For me, that would be 220 - (0.7 x 74) = 156 bpm, a bit better but still absurd. 

Wikipedia notes that although these kinds of formulae are fairly good at estimating the average heart rate of a population, individual athletes can have maximum heart rates that are 30 bpm higher or lower than that average. For me that would be 116 to 176 for the first formula and 126 to 186 for the second. The fact that Mayo did not discuss or allow for this should have alerted me to their lack of sophistication. In fact, even back in 2012, I rejected the advice of Mayo on how to determine maximum heart rate but then failed to be as skeptical of the rest of their recommendation. It was only when their advice changed so dramatically that I called the entirety of their recommendations into question. What was the basis for their new recommendation?

When I researched Heart Rate Reserve, I found that it is associated with a Norwegian exercise scientist by the name of Martti J. Karvonen. Karvonen himself proposed definitions for Moderate and Vigorous exercise which, like Mayo's new definitions, use Heart Rate Reserve, but uses significantly different percentages to define the zones: 40% to 60% for Moderate Intensity and 60% to 90% for Vigorous Intensity. For me, that works out to 114 to 136 bpm and 137 to 169 bpm, respectively. Interestingly, these ranges are close to the definition of Hughes Zone 2 and Zones 3 + 4, respectively, and they match the recommendations of both the American College of Sports Medicine (ACSM) and the Centers for Disease Control (CDC) which the recommendations of Mayo do not.

Perhaps Mayo was simply the wrong choice of an institution. Perhaps I should follow the ACSM either directly or via the larger entities that pick up their advice, organizations like the CDC. One reason not to do that is that both the ACSM and the CDC use one of those age related formulae (220 - age, 208 - 0.7 x age) to determine maximum heart rate, an approach in which I do not believe and which does not work for me. Besides Wikipedia, many coaches object to this approach as well. Why then is the medical establishment so in love with these formulae? I don't know, but if I had to guess, I would say the medical community would defend themselves by saying that direct measurement of maximum heart rate is extremely difficult and even dangerous. In order to not let best be the enemy of good, they went with the less accurate but much easier and safer formulae above. They might acknowledge that I am a patient for which these formulae do not work but then note that there are many patients for which they do and so they have to reluctantly sacrifice me in the interest of helping the majority of patients.

But what is the scientific evidence in favor of any of this? I have researched this and as best I can tell there is little to no scientific basis for assigning any heart rate ranges to the Moderate and Vigorous levels of exercise. The medical community believes there are lots of health benefits that result from aerobic exercise; the ability to complete everyday tasks, reduction of depression, for example but the main benefit that is studied is reduction of "premature" death. The word "premature" here might seem a little confusing but what it really boils down to is how long you will live. If you engage in aerobic exercise you will, on average, live longer. Estimates of how much longer vary wildly (5 months to 7 years) and that wild variation is both interesting and humbling but is beside the point for this post. What we are focusing on here are how Intense that exercise should be, and, given an Intensity, how much should one ideally do? The official guidelines suggest that, ideally, one should do 300 minutes per week of Moderate exercise or 150 minutes a week of Vigorous exercise to maximize lifespan. This is based on a wide range of research, but perhaps the most relevant is that which asks people how long and how intensely they exercise. So finally we get down to it: what measure of Intensity is used in such studies? The most common one is based on the kind of exercise: walking, jogging, running, swimming, cycling, etc. Walking is Moderate. Jogging or Running is Vigorous. And most interestingly, all Cycling is counted as Vigorous exercise! I truly believe that the authors of these studies are well aware of how crude a measure this is, and once again, that results from not letting best be the enemy of good. As imperfect as this classification is, it is the best data that is available. The reason there are no scientific studies of this kind that use heart rate to classify Intensity is because so few people who might be in these studies have heart rate data. I do not believe there is any scientific evidence supporting the assignment of heart rates to the medical Intensity zones of Moderate and Vigorous, the best one can hope for is common sense. My common sense tells me that the new Mayo estimates are far from correct. For now, I am going to use Coach Hughes' Zone 2 as my definition of Moderate Exercise and Zones 3 and above for Vigorous exercise. In addition, I will use the results of Gillen et al. to define an Interval Session consisting of six all-out 20 second sprints separated by two minute recovery periods as providing the same benefit as 90 minutes of Moderate exercise. I am far from certain that these definitions are accurate and I am open to revising them should I encounter reliable evidence suggesting better definitions, but I feel like they are the best I can do for now.

While researching for this post, I came across those who dismiss heart rate as an acceptable way to discover Intensity Zones and who advocate in favor of ventilatory threshold,  respiratory exchange ratio, or blood lactate levels. If they are experienced coaches who have used this kind of data to improve the results obtained by their athletes, then I take them very seriously. If, on the other hand, they are advocating for using these measurements to establish the boundaries of Moderate and Vigorous exercise on purely theoretical grounds, then I will remain skeptical. If they want to convince me, they need to provide actual experimental evidence supporting their arguments. I don't believe there is any such evidence but very much hope to be proven wrong.

 I would like to propose a contrarian hypothesis of my own: 

"The bulk of the increase in longevity that comes from aerobic exercise comes from the fact that such exercise strengthens the heart muscle. Thus, heart rate is the perfect thing to measure to study the benefits of aerobic exercise. However, there are no Moderate and Vigorous zones, rather there is a continuum. The higher the heart rate during exercise, the faster the benefit is accrue and the relationship between heart rate and the benefit per minute is a smooth (if not necessarily linear) curve. It is your choice, cycle slowly for many hours or sprint all out for a few minutes, it's all the same." 

Do I really believe this hypothesis? No, it is a straw man argument and, at best, an oversimplification. Very few people read this blog and I doubt that any of them have any influence in the exercise and health branch of biomedical research but if this post were being studied at the highest levels of the health establishment, what would I want them to do with this hypothesis? I would want them to design and execute experiments to test it, not as a true or false binary, but to ask the question if there is any truth to it at all, and if so, how much?

So where do I go from here? Nowhere, as it happens. In all my years of cycling, I have never changed how or how much I cycle to try to improve its health benefits. My hypothesis has been that the most important thing for my health is to keep cycling, so I do whatever keeps me motivated. Perhaps there has been some thought that "the more cycling, the better" and every scrap of research I have ever come across has supported that. Of course, that cycling needs to be sustainable, overtraining in the short run leads to less cycling in the long run so, especially as an old man, I need to avoid that, but with that in mind I will follow the advice of the famous medical research scientist, Eddie Merckx: "Ride lots."

Preparing for Survival

 

...the Art of Survival Metric Century that is. This post can be seen as a companion to my 2019 post "Training for the Golden Hills" and could have had a similar title but, for better or for worse, I tried to be clever.

I have ridden The Art of Survival three times now, in 2018, 2019, and now in 2024. In 2020, the event was cancelled due to COVID. In 2021, I had trouble training for the ride so decided not to go, a decision I still question. In 2022, I feel like I was as prepared for this ride as I have ever been but didn't go at the last minute due to severe weather. 2023 is the year my back decided to get much worse and so I couldn't go again. For 2024, I desperately wanted to get my cycling back on track and successfully completing The Art of Survival was an important milestone on the way to doing that. I did attend and I did finish but somehow that was not enough. Why not? Or to ask that question in a different way, what do I mean when I say successfully completing the ride?

In my post about Training for the Golden Hills, I defined success as "a comfortable ride from beginning to end" and this year's Art of Survival certainly was not that! To be fair, a lot of my discomfort had nothing to do with my training. This year's ride was extremely windy. Many of the roads on this ride suffer from frost damage which results in cracks across the road and riding over them felt like someone hitting my handlebars with a sledgehammer about once a second. And then there were the swarms of insects. Yes, I am something of a whiner, but as I was enjoying the excellent lunch provided at the end of the ride I noticed I was far from the only one complaining about these things. Some of my discomfort resulted from the effort required to get to the ride. The seven hours of driving followed by moving my luggage and bike in and out of a second story hotel room left my back very sore. Cycling does not make my back worse but neither does it reduce any back pain that might be there. On top of that were other aches and pains of old age, my left knee, my right shoulder, etc. A final issue was psychological. If I perform well on a ride the happiness produced by that success makes that ride a lot more fun. I did not feel like I was performing well on this ride.

All three times I have ridden The Art of Survival I have ridden it with my High School riding buddy, Roger. In 2018 and 2019 I rode a normal bike (not an eBike) and both years I had trouble keeping up with Roger but I did finish under my own steam. For the 2022 Ride the Rogue, Roger and his brother-in-law David suggested that I ride my eBike to make it easier to keep up and that worked. Most of the time I rode with the eAssist turned off but when we got to a hill that made it hard for me to keep up I would switch it on. Because the eAssist was mostly off, I still felt some satisfaction from the ride. This year I hoped for a similar experience. In my optimistic moments, I even hoped I might not use eAssist at all. What actually happened was quite the opposite. I used the eAssist for almost all the ride and there were times I struggled to keep up with Roger even using eAssist. Although this was not physical discomfort, it was demoralizing and contributed to the lack of a feeling of success. After all, it was an electric motor that brought me to the finish, not my training.

But what does any of this have to do with the title of this post? How had I prepared for this ride and how did that preparation work out?  My training plan for the 7 weeks leading up to the ride was as close to a well thought out plan as I have managed in a very long time. As I result, I had hoped for a successful ride. There were, however, warning signs. The longest training ride I did in preparation for Art of Survival was 47 miles, 78% of the length of the ride which is plenty long, but I found it very difficult to complete and my average speed on that ride was low. Back in 2021 I decided not to attempt The Art of Survival because, although I completed a very similar 43 mile ride, my speed on that ride was only 11.2 miles per hour and I could not follow that up two weeks later with a 54 mile long ride. This year, my first 47 mile long ride was ridden at 11.3 miles per hour and two weeks later, although I completed a 46 mile long ride, I could not extend that ride to 57 miles as I had hoped I might. Thus, my successful training plan of 2024 looked a lot like my failed training plan of 2021. I was OK with that for several reasons. First, I thought I probably should have ridden Art of Survival in 2021. Second, my 46 mile long ride in 2024 was faster (11.6 miles per hour) and more comfortable than the ride two weeks earlier. Third, I have reconsidered the schedule I developed for The Golden Hills in 2019. I think a 55 mile long training ride is excessive as preparation for a Metric Century. To summarize, I think that it was the right decision to go ahead and ride this year and although my preparation was just fine, both the the length of my longest training ride and the speed I was riding were lower than in 2019 and so I think I can reasonably conclude my fitness was lower.

Why was my fitness lower? Starting with the most likely reason, I am 5 years older in 2024 than I was in 2019 and, at my age, that has to make a huge difference. All by itself, this could be the whole explanation for why I was more fit in 2019 than I am today. Unfortunately, there is nothing I can do about my age. Might there be contributing factors, something under my control? There are. In 2024, there was a lack of year around consistency in my training. Although the training schedules for 2019 and 2024 (shown above) look similar, some of that is an illusion. Seven weeks before The Art of Survival I began a very sensible training program but 10 weeks before that my fitness was very low because for the previous 18 weeks I did very little riding. Thus, as good as my 7 week program was, I was starting in a hole. My 2019 Golden Hills came at the end of a very active season and thus benefitted from that entire season of riding. In 2019, rather than starting in a hole, I was starting on a hilltop. To put that in concrete terms, I rode 3025 miles and averaged 338 minutes a week during the year before The Golden Hills but rode only 2625 miles and averaged only 283 minutes a week the year before Art of Survival. The good news is that I seem to be making some progress on this front, a topic for a future post. Finally, as good as my training during the 7 weeks before The Art of Survival were, there might be some room for improvement there as well. As just one approach towards that end, I continue to experiment with the Banister model of Form, Fitness, and Fatigue, most definitely a topic that needs to wait for a future post. Stay tuned.

50,000 Miles ... and now what?

This is my third round number of my miles posts. I posted The first one after I had completed 20,000 miles of riding. I started out that one with a quote from my wife: "You should be proud of yourself for sticking to cycling so long." That continues to be the most important thing about my cycling, that I have now stuck with it for more than 15 years. I believe that the impact of that consistent exercise has been enormously beneficial for my health. My second post came after 40,000 miles of riding. In that post, I predicted I would reach 50,000 miles in September of 2023. That was a bit optimistic, but I am extremely satisfied to have reached that milestone even if a bit late. 

Here is another optimistic prediction from that 40,000 mile post: "It is not impossible that, even riding against [the] headwind [of my old age], I might still be able to get a bit more fit than I am today." I no longer believe that is possible. Rather, I believe that I am engaged in a rearguard action to delay my decline and continue cycling in at least some form for as long as I can. 

Each of my three round number of mile posts have opened with a similar graph - my accumulated miles since I restarted cycling in August of 2008 through the present. For this one I added a trend line (in red) to help reveal times during those 15+ years when I have ridden more or less than average. Looking at my progress compared to that trend line, it is apparent that I am slowing down. Given that, how much longer can I keep this up? There is no way to know, of course, life just happens, but one can ask about the odds. A good starting point is to ask how much longer I might expect to live. Social Security provides a very basic prediction based only on my sex and current age and predicts I will live 12 more years, to age 86. To provide a more personalized and possibly more accurate prediction, I searched the Internet and found a government funded, peer reviewed (which is to say believable) research project at Boston University named Living To 100 that asked me a large number of questions about my weight, drinking, smoking, exercise, etc. Based on all this data about me, their algorithm also predicted I will live 12 more years, to an age of 86. But that is just an upper limit. It would be lovely if I could finish a bike ride, sit down by the side of the road, and peacefully pass into the hereafter, but the fates are seldom that kind. It is likely that I will be unable to continue cycling some time before the end of my life. 

To help me think about what the future might hold I have collected stats on all my previous 10,000 mile landmarks, whether I blogged about them or not, and then made some reasonable assumptions and projected forward to the next three 10,000 mile landmarks:

The key column in this table is the last, labelled Years. The more years it takes to complete 10,000 miles, the less riding I did on a per year basis. As can be seen on both the graph at the top of this post as well as in the table above, my first 10,000 miles were an outlier. One reason for that is, as I noted in my 20,000 mile post, the start of my second cycling career on 8/1/2008 was something of a false start. After cycling for about six months I stopped cycling for well over a year before restarting again on 5/3/2010. This long gap with almost no rides and thus almost no miles dramatically distorts the statistics. I tried a number of different ways of correcting for that and all of them make that first year less of an outlier, but in all cases the First 10,000 miles was slower than the Second 10,000 miles. From this I conclude that my cycling was improving during those first 10,000 miles. This is the second reason that the First 10,000 miles is an outlier: after that landmark, everything is downhill.

For each 10,000 miles (except for the first) the number of years required to complete those 10,000 miles is greater than the 10,000 miles before by about 6 months. To project what I might be able to do in the future, I assumed that trend would continue. Will I be able to reach a 6th 10,000 miles? There certainly aren't any guarantees, but barring any problems (a bit of an assumption at my age) it is certainly possible. How about a 7th? Should I be able to do that, I would count myself lucky indeed! I would say a 7th 10,000 miles is unlikely but not impossible. To complete an 8th 10,000 miles would require me to ride two years past the date projected for my death. Of course, the date of my death is impossible to predict precisely, and so nothing is impossible, but I am definitely not counting on reaching that milestone.

There are other reasons I believe my fitness is decreasing:

• From 2012 through 2015 my goal was 200 kilometer long rides. By 2018, I had lowered my goal to half that, 100 kilometer long rides. Of course, it is more complicated by that. By 2018 I had moved to hilly California from flat Texas and my goal was one 100 kilometer ride a month rather than one 200 kilometer long ride a year, but all things considered, I believe this was a step down in ambition.
• In 2021, I failed at even this less ambitious goal. I attempted to train for the Art of Survival Metric Century (100 kilometers) and fatigue prevented me from doing so. (I have blogged about that failure ad nauseum and may do so again.)
• In 2023 my back got worse. Although this does not affect my cycling directly, going for a ride is one of the most comfortable things I can do with regards to my back, but my back pain does create fatigue and thus inhibits my cycling indirectly.
• Recently, I realized my dream of riding a Metric Century a Month was never going to happen. Although this is not an event but rather the acknowledgement of a reality, I think I wouldn't have been driven to this acknowledgement except that I am no longer feeling as strong as I did when I first had that dream.

Cycling for Health

The primary reason I restarted cycling back in 2008 was because I realized my lack of aerobic exercise was threatening my health. The Medical community recommends I accumulate a minimum of 150 minutes a week of Moderate Intensity or 75 minutes of Vigorous Intensity aerobic exercise a week. Ideally they would have me accumulate twice that, 300 minutes Moderate or 150 minutes Vigorous Intensity a week. They also recommend that exercise be spread out over the week. For example, they suggest a 60 minute Moderate exercise session five days a week, with a recommended minimum of 3 days a week. For the purposes of this post, I am calling all my cycling Moderate Intensity even though I know that is not completely true. I am hoping it is a close enough approximation but will call out one case where I think that assumption might be problematic.

For the purposes of evaluating how my health-targeted cycling is going, I am going to look at two statistics: for what percentage of the weeks did I accumulate 150 or 300 minutes of cycling, and for what percentage of the weeks did I ride for 0, 1, 2, 3, 4, 5, 6, or 7 days? During my most recent landmark, 40,000 to 50,000 miles, I rode 150 or more miles during 78% of the weeks and 300 or more miles during 51% of the weeks. I did five or more rides during 39% of the weeks and three or more rides 77% of the weeks. So, not nothing but far from perfect.

Historically, I have not worried about riding for health per se, I figured my recreational riding should provide the health benefits I was seeking but is that true? My gut says yes but my annoying brain remains skeptical. I have blogged about the medical community's aerobic exercise recommendations a fair bit and plan to blog about it more in the future but very briefly, I take comfort from the following quotation from "Physical Activity Guidelines for Americans, 2nd edition" by The Department of Health and Human Services USA, 2018: "Some physical activity is better than none. Adults who sit less and do any amount of moderate-to-vigorous physical activity gain some health benefits." Similarly, I am inspired by the following quotation from the same source: "Additional health benefits are gained by engaging in physical activity beyond the equivalent of 300 minutes (5 hours) of moderate-intensity physical activity a week." So mostly I am going to go with my gut on this one. What I am doing is way better than nothing but I should continue to strive to bicycle as much as I can.

What does it mean, "mostly go with my gut"? Well, my brain has an important role to play here, and that is keeping me honest. One example of where this is an issue is the Recovery Rides on my trainer. One thing I hope to blog about in the future is the difficulty in distinguishing between Light, Moderate, and Vigorous aerobic exercise, but for the purposes of this post I am going to claim that those Recovery Rides are at an Intensity below Moderate so that I should not count them towards my health benefits. Unfortunately, the statistics I quote above do include them. At the time I was recording them, I believed they did count as Moderate exercise and now it would be too much work to go back and remove them. Does that mean I am doing even worse than I thought? Maybe not. Although I counted my Recovery Rides when I shouldn't have, I also ignored that part of my riding that is clearly qualifies as Vigorous or even HIIT. HIIT stands for High Intensity Interval Training. Here is what The Department of Health and Human Services (HHS) says about HIIT: "Recent research has examined high-intensity interval training (HIIT), which may provide similar reductions in cardiovascular disease risk factors as those observed with continuous moderate- intensity physical activity." HSS goes on to say that research remains to be done on exactly how much HIIT should count. The research I am reading says that, whereas minutes of Vigorous exercise counts double, minutes of HIIT may count as much as 45 times as much as Moderate exercise. So, for the purposes of this post I am going to hope that erroneously counting my Recovery rides is offset by failing to fully credit the parts of my rides that are Vigorous or HIIT. Of course, this assumes that I don't over-use my trainer (see below.)

Finally, how does my success during my last 10,000 miles compare to my previous 10,000 mile landmarks? During none of the five 10,000 mile landmarks was I perfect; I did not cycle 300 miles or more and 5 days or more for 100% of their weeks. The graph below illustrates how much I did ride for the last four landmarks:

I didn't include my first 10,000 miles on this graph because, as noted above, it was an outlier and including it made the graph harder to understand. The red line on the graph is average minutes per week, equivalent to the how many years it takes me to finish 10,000 miles already noted above as a declining indicator, and it is indeed declining. This is related but not identical to the percent of weeks in which I rode greater than 300 miles. The key difference is that, for the latter metric, it doesn't matter by how much I exceed 300 minutes whereas for the average, it very much does. My longest week, the week of my first 200 kilometer long ride, I accumulated 909 minutes while riding 197 miles. This week dramatically affects the average but counts no more than a week with 301 minutes towards the percent of weeks >300 minutes.

Looking at this graph, it is the case that my second 10,000 miles had the best score in all categories, but for the third, fourth, and fifth, each landmark may be better in one but worse in another. Especially relevant to this post, my most recent 10,000 miles had the worst score for percent weeks with greater than 300 minutes, but a pretty decent score for number of weeks with five or more rides; my consistency is good but my rides are too short. I feel like the overall message is that my performance on these metrics is declining overall but with some ups and downs along the way.

Cycling for Fun

I reached the 40,000 mile landmark during September of 2020, just about the time I moved from a relatively flat part of San Carlos to the well named Emerald Hills where I now live. This was during the peak of the COVID-19 pandemic and as a result all 2020 cycling events were cancelled. However, that didn't mean I had no fun. Rather, it meant the fun I had was that of exploring a new neighborhood and figuring out how to deal with its challenges, especially the hills. After the move, I could continue to ride my two favorite GoTo rides, my Alpine and Alpine-Cañada rides, almost unchanged. As for new rides, my son shared one of his favorite rides with me, the Huddart Park ride. It is a delightful ride in many ways, low traffic, amazing scenery, and at first I did one of these rides a week, but it is also a very challenging ride and I found I was building up fatigue and, as a result, started looking for alternatives. I tried coasting downhill from my new home to my old haunts in the flats of the East Bay to do some of my favorite rides there but always ran into the same problem. The hills back to my house from the east are all very steep and this converted what was supposed to be an easy ride into a hard one. (The reason the Alpine and Alpine-Cañada rides work is because they bring me home from the west where the hills are less steep.) Similarly, when I tried to explore my new neighborhood (one of my favorite things to do on a bike) the very steep hills made that extremely challenging to impossible, even for my Bianchi Volpe, my bike with the lowest gears. In fact, the new neighborhood had reduced my formerly respectable stable of bikes to a single usable bike, the Volpe being the only one with gears even close to low enough for the neighborhood. I knew I needed to find an easier ride. My first attempt was the Lake Loop. I rode that ride so many times I became a Legend on Strava. The ride itself was fine, but getting home from it was still too hard. Several years ago I had purchased a trainer but found it so boring I didn't end up using it very much. I set my trainer up in my bedroom with my Surly Cross Check dedicated to it, making it super convenient to use, I just hop on and go. It is still boring, but it allows for a very easy ride to help balance all the hills and so I find myself using it a couple of times a week. 

In early 2021, my son decided that I needed an eBike. Because of the pandemic, bikes were hard to come by, but he found an exceptionally good bike that I could get right away, an Orbea Gain. It arrived March 24, 2021 and by March 28th I had it set up and completed my first ride, that exploration of the neighborhood which that eBike finally made possible. The other thing it made possible was keeping up with riders who are much faster than I am, my son and my friends Roger and Dave for example. One of the most fun set of rides I did on that bike was one we called the Hot Chocolate Ride. The pandemic was still in full force so eating indoors at a restaurant was out and restaurants had not yet had time to build out the outdoor seating which they all have now. However, there was one restaurant that had always used outdoor seating and so Sundays, we would ride over the (steep!) hills to that restaurant, Michael on his normal bike, his wife Robynn on a cargo eBike with Julia and Elliott aboard, and me on the Orbea. When we started these rides, I was on my Volpe but Michael and Robynn had to slow down so I could keep up. Once I had my Orbea, they could ride as fast as they liked and I could keep up with them.

By 2021,  Art of Survival had come back after the pandemic, but when I attempted to train for it, fatigue prevented me from doing so, something about which I have blogged ad nauseum and which I may blog about even more in the future. I concluded at the time that this failure was due to overtraining and reacted accordingly. As time goes by, I become more and more skeptical of that conclusion and worry that my response to that hypothetical overtraining may be doing more harm than good, an issue to which I will return later in this post. One consequence of that was between the middle of 2020 when I moved to the start of 2022, with the exception of the Hot Chocolate rides, the only ride I did with anyone else, that I did not do all alone, was one ride with my friends Paul and Fringy.

2022 was a very good year. I began by riding with Paul and Fringy in February, April and July. In March, I completed a ride on my Hetchins with the local Classical and Vintage bike group. At the end of April/beginning of May I attended Eroica California. I successfully prepared to ride the Art of Survival at the end of May, but then couldn't attend due to bad weather.  Instead, I was able to attend Ride the Rogue in September of that year. This was also the year I got my TranyaGo sports watch and restarted tracking my heart rate.

2023 started out as another bad year due to a combination of my back getting worse and coincidentally, some severe dental problems. These exhausted me and my riding suffered. This reached a nadir in May, making attending Art of Survival impossible. Starting in July, my riding got better so I might have hoped to attend Ride the Rogue, but I had a scheduling conflict. By October, my riding again got worse due to a random combination of interruptions, weather, and illnesses. January 2024 was a continuation of that poor performance, but by February I started to improve again. If this continues, I am hoping to attend Art of Survival this year.

Final Thoughts

My gut is telling me that the big picture presented by the time course of my 50,000 miles of cycling is that I am getting older and that my ability to ride is fading as a result. My brain is not entirely convinced. One argument that my brain makes is to point out a possible wrong turn in my training that I may have made back in 2011. One explanation of my poor performance that year was overtraining and I really leaned into that one possibility. Two things I did which my brain is questioning are 1) I started overusing my Trainer, and especially riding too often at too low an Intensity. These are not training rides. One or two of these a week after a strenuous ride might help me harvest the benefits of that strenuous ride, but in excess of that, represent junk riding of no significant benefit, and yet I am counting them in my training statistics, giving myself a false sense of progress. 2) I started riding my long rides more slowly. There were logical reasons for doing that, the 80:20 rule (aka Polarized Training aka Zone 2 training) recommended by many coaches, for example. What my brain argues is that maybe I overemphasized the 80 and underemphasized the 20, that when I made my long rides easier I was not careful to make sure I included enough fast rides and to make sure that they were fast enough. Similarly, when I made my long rides slower, maybe I should have made them longer at the same time. Now my brain will concede that this is just a possibility, that I definitely need to listen to my body, and when my body says it is tired, I should act accordingly. In retrospect, however, even my gut will concede that I really overdid the easy trainer rides. In summary, maybe I should make sure that when I am riding less it is because I am tired not because I am lazy. Who knows, Paris-Brest-Paris* for my 90th birthday? (Just kidding.)

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* Paris-Brest-Paris is perhaps the most prestigious group ride there is. It is about 750 miles long and must be completed in 90 hours to qualify for an award. Sleeping is allowed but it does count against your time so sleep deprivation is common. It is tough, even for a very fit rider in their prime.