Saturday, September 27, 2014

Hanging It Up

This picture illustrates a number of points in this post: 1) The hanging bike illustrates the title of this post; once again, the vagaries of life have interrupted my randonneuring plans. 2) My dad's work clothes to the upper right of his walker. We were sad when Dad was driven to use a walker, making the use of his work clothes a thing of the past. Now, we just hope he can return to the walker. 3) The bike itself. My carefully crafted plans to prepare for a 200K brevet in November may be at risk, but even while taking care of Dad, I have a bike to ride.

"Man proposes, God disposes."1 For my first two brevets, in 2012 and 2013, I used long, rigid training plans to prepare. As regular readers of this blog know, I selected a much more relaxed training plan to prepare for a 200K brevet this November. It is so flexible, it should be resistant to most of life's surprises. Surprise! A few weeks ago I received a text from my sister: "Dad has fallen." A few days after that, "Dad has fallen again, and is in the hospital getting x-rays." I am delighted that the x-rays revealed no broken bones, but what about the next fall? My father-in-law died from such a fall. So, I post this from Dad's home in California where I am staying to both share in Dad's care as well as to help him plot the next stage of his life.

I prepared this post before leaving Houston; Dad's technology resources do not lend themselves to preparing a blog post, nor do I have access to my library of pictures and cycling data here. That being so, this may be the last post for a while, which is its main message. That, and that my plans for a 200K brevet in November are on hold, perhaps to be abandoned. I will ride as much as I can in California, but between the needs of my father and the absence of my familiar cycling environment, training for a brevet may be more than I can do. But who knows, I will ride as much as I can, substituting intensity for distance, and depending on how quickly my sister and I can get Dad settled, I will see how long it takes me to get back home and what my fitness looks like when do. Stay tuned.

1) A translation from "The Imitation of Christ" by the German-born Thomas à Kempis (c.1380-1471). I claim this proverb is religion neutral. Either take it at face value or use God as a stand-in for fate, luck, nature, the perversity principle or Murphy's Law, as you prefer.

Thursday, September 25, 2014

Fitness Smorgasbord

I was the team photographer for the Berkeley Wheelmen while I was in college in the late 60's/early 70's. This is a picture I took of the sprint at the end of a road race. I have included it here to illustrate the concept of training rides ridden at a brisk pace (e.g. intervals.)

Even though I am not an expert on cycling or training, I do value my own experience. That said, there is an extra confidence that comes when I meet a fellow traveler who has come to the same conclusion I have. This happened to me while reading a recent column by Lovely Bicycle. I had been speculating about the efficacy of using brisk training (intervals) to prepare for long rides and she speculates about the same thing. Additionally, Bicycling magazine has weighed in on the topic. As a follower of Bicycling on Google+ (yes, somebody actually uses Google+) I am offered articles on new training plans at least once a week. Examples include "Interval Training for Weight Loss - Burn More Fat", "Ride Faster in Three Days Per Week", and now, in "Quick Cycling Workouts for Power and Endurance." The last article presents a schedule of intervals that Bicycling Magazine claims will improve endurance. Honestly, I cannot tell if they are saying these specific interval schedules are good for endurance or if intervals in general are good for endurance. I hope it is the latter, because the intervals I have been doing don't look anything at all like these.

Another lesson I think I have learned is that it is much better to slightly under-train than to slightly over-train, that when in doubt, I should train less. Recently, Bicycling published an article about Meredith Miller, a professional cyclocross racer, who claims "she doesn't train." An actual reading of the article suggests something closer to what I have been finding; a valuing of resting over training. Once again, it is a comfort when I have made a discovery on my own and I am wondering if it is true or an illusion, to read about someone else making the same discovery.

When I restarted cycling, one of my first influences was Philip Maffetone. He advocates the virtue of training at a low heart rate, roughly Zone 2 on the Zone 1 through Zone 5 system I use. Zone 2 is a relatively easy ride; the test for the proper level of effort is that one should be able to talk in complete sentences while riding in Zone 2, but not sing. Since first encountering Dr. Maffetone's ideas, I have remained both interested and skeptical. Thus, it was of great interest to me when, once again, Bicycling Magazine published an article about the great success Tour de France veteran Fred Rodrriguez had with a training plan consisting entirely of training in Zone 2.

One of the most seductive fallacies in statistics comes from failing to correct for multiple sampling. In a statistical analysis, the result can often be expressed as a P value, corresponding to the chance that the result observed could have occurred by chance. The most common cutoff for statistical significance is P=0.05, meaning that there is only 1 chance in 20 that the result being tested is due to chance. However, if you do 20 different experiments, you are likely to see such a correlation even if all of them are random. Bicycling magazine publishes so many different training plans and articles about training, I have to wonder if I could find one to support almost any training idea I ever had; is this support even meaningful? One the other hand, the article by Lovely Bicycle may well be the only training article she ever published. That one I can take to the bank!

News Flash

On of my most common rides starts at my front door, goes about a mile on city streets to the middle of the Braes Bayou multi-use trail, and then heads west on that trail to its termination at Gessner Road. This is a 17 mile ride, round trip. About four or five months ago, I noticed construction at the end of the trail that promised to lengthen this ride, a welcome change. Unfortunately, after the initial construction, everything seemed to stop. Thus, I was enormously excited today when I got to the end of the trail to see that the previously dirt extensions were now paved:

This trail extension is not yet open, but it seems we are getting closer. I can't wait!

Wednesday, September 17, 2014

Tour de Pink 2014

Teams are a big part of the Tour de Pink. This is the team my wife and I rode for, the University of Texas Medical School, Houston (UT). From left to right is the zombie himself (team member by marriage), his wife (faculty at UT), our team captain (faculty at UT), and two UT graduate students. Not shown due to late arrival is the sixth member of the team, another faculty member. All teams, including ours, vary in size year to year. This was one of our smaller years. And yet, we were just about in the middle of all the teams in the amount of money raised.

This is the fourth year my wife and I have ridden the Tour de Pink, a ride that, besides being a delight to ride, supports an excellent charity. I have written about the Tour de Pink twice before, in 2012 and 2013, and I won't repeat myself in this post, so refer to those earlier posts if you'd like additional information about this ride. At least over the four years we have been riding, the ride changes very little year to year, the routes for the various distances are exactly the same for example.

My son and daughter in law are visiting us. My son was ill and was unable to join the ride, but my daughter in law grabbed her bike, joined us, and completed the 63 miles with no training. What a champ!

I had been aware of the Tour de Pink for some time because Baylor College of Medicine, where I worked, was a major participant. I could have ridden it as early as 2008, and don't really know why it took me until 2011 to finally do so. For that first year, my wife and I didn't do any special training for the ride. Our weekly long ride was usually in the 35 to 40 mile range, so we figured 47 miles was well within our grasp as it proved to be. In 2012, we set our sights on the next distance up, 63 miles, and were well trained for that distance when life intervened at the last minute, limiting us to a 12 mile ride. In 2013, we were finally able to train for and complete a 63 mile ride. My wife was beat by the end, not due to lack of training, but due to the heat. She resolved that, in future years, she would not try any of the longer routes, but work on riding faster so she could finish earlier in the day, thus beating the heat. That turned out to be a non-issue this year; the weather was delightfully cool, staying between 60 and 70 degrees for most of the ride. Should we have tried for a longer ride? That would require longer training rides, and although we were lucky and had cool weather on ride day, most of our training rides were done under extremely hot and humid conditions, discouraging us from making them too long. Our longest training ride this year was 48 miles, and with that as a base, my wife was able to complete 63 miles at a personal best average speed of 14.5 miles per hour. However, by the end, she was ready to finish; I do not think it would have been wise for us to try for a longer ride this year, even with the perfect weather.

As the sun rises to the right of the next picture, we begin the ride in the same way as the past three years, with the Star Spangled Banner and the riders released longest riders first.

This is the start of the race with the start marked with the same display I have shown in prior years. My wife is Team GPCR (an esoteric scientific reference that delighted her teammates), I am in front and to the right of her, looking to the right, and the woman hidden in shadows with no bike is the "starter" for the 63 mile group.

Last year, I raved about the mini-sausages at Pit Stop #5, but had not gotten a picture of them. This is remedied this year, in the next picture, which also shows some of the other treats.

Whenever a lot of people gather in public places to do something, there is a natural tension between the worthiness of the activity and the enthusiasm of the participants and the tendency for such a large group to be a bit of a disruption. People living near the pit stops are not, in general, delighted to have bicycles dumped on their lawns. This year for the first time the organizers addressed this problem by providing bike racks of a novel design. The bike is supported by hanging either the handlebars or seat over the cross bar. This completely solved the problem, no more loose bikes on neighborhood lawns.

My daughter in law, exasperated at having her picture taken. I actually am including this picture not to exasperate her but to show the bike racks.

The next picture shows me and my wife at the finish. The tents in the background is where lunch was served. You can also see the tables provided for eating lunch.

Every year a goodie bag is provided. Constant each year is a water bottle and a T-shirt, with the rest of the ingredients varying from year to year. In my opinion, the contents this year were the best ever. Among them were not one but two blinkie-lights, shown below. Since everybody was given them, and since assembly began before dawn, the vast array of blinking lights was truly awesome!

Events can be fun because they are completely novel, or because they are friendly and familiar. Tour de Pink definitely falls into the latter category. By and large, the route is great, with wide shoulders, low traffic, and pleasant scenery. By now, I pretty much know where I am at any point along the route, and how far it is to the next pit stop. And best of all, I am starting to know enough of the regulars that I have a set of old friends to greet here and there along the way. Stay tuned for my report on the 2015 edition of Tour de Pink.

Thursday, September 4, 2014

Thoughts About Fatigue

The Zombie and one of his fellow Modesto Roadmen in 1965, at the very beginning of their cycling careers, exhausted from an overly-ambitious bike ride.

What is fatigue? On the surface, this seems like a dumb question. Everyone knows what fatigue is. However, as I have been "training" over the past three to five years, as I have thought and read about this question, and as I compared my personal experiences to what I read, I have continued to wonder about the following questions:
  1. Is all fatigue the same, or are there different kinds of fatigue?
  2. What are the underlying physiological causes of fatigue?
  3. What are the best responses to fatigue? Does it differ depending on the kind of fatigue?

In response to question 1, I have tentative concluded that there are different kinds of fatigue. One reason I suspect that is that recovery from fatigue occurs at very different rates, depending on its cause. This makes me suspect that fatigue, like pain, is a symptom that can be a signal for a range of underlying conditions. At one extreme, there is the fatigue and rapid recovery (seconds to minutes) that occurs between intervals of interval training. I believe that this fatigue is fairly well understood. Fast twitch muscle fibers are active during the interval, using either creatine phosphate or carbohydrate as fuel. There is only a few seconds of creatine phosphate available, so it is soon exhausted. When carbohydrate is used as a fuel during intervals, it is metabolized anaerobically, generating lactic acid, which contributes the the sensation of fatigue. During the rest between intervals, aerobic metabolism regenerates the creatine phosphate and metabolizes the lactic acid, which allows me to ride the next interval.

The need to regenerate the fuel for fast twitch muscle fibers is not the only kind of fatigue I experience during interval training. After half an hour or so, I cannot do any more intervals, rest period or no. In fact, it will be two or three days before I can do intervals again. Why is that? The conventional explanation is that muscles are damaged by the intervals, and that days are required to repair the damage. I confess that it doesn't make sense to me that something as natural as exercise should damage muscles, but everyone seems to believe it is so, so I guess I have to accept it as true. However, this raises a further question: does muscle damage result only from the intense effort of interval training, or does it result from easy rides as well? My experience suggests that, if not the same thing, then something similar happens on slow rides, albeit at a slower rate. After I complete a day of intervals, my legs feel tired for the rest of the day; it is difficult for me to walk up stairs, for example. If I do a long ride at slow speed, I have the same sensation. Also similar is that it takes me days to recover from a long ride. If anything, it takes me longer to recover from a long, slow ride than it does from an interval workout. In fact, I have the subjective impression that long rides are the hardest to recover from and are the biggest cause of overtraining. This difference in recovery makes me wonder if fatigue from a long ride is signaling a different underlying cause than fatigue from an interval workout.

Another well known kind of fatigue that has a similar recovery time is bonking. This results from exhaustion of the glycogen reserves in the muscles. I happen to be fairly resistant to bonking, but have bonked once or twice and for me, despite eating extensively, I did not recover until the next day. This seems to be what others experience as well. The oft given advice to eat constantly on a long bike ride is intended, I think, to spare the glycogen reserves rather than to replace them, as the speed of replacement would appear to be too slow to be useful. I think bonking is a bad thing and should be avoided, but I suspect that it does not have a lot of long term consequences, and thus I will not discuss it further.

The kind of fatigue that is the most puzzling to me is that associated with overtraining. For me, this can take weeks to months to recover from. The classic explanation given for overtraining is illustrated in the following two figures (both from the Runner Academy website):

This first figure is the classic description of training; for each time you train, you first lose fitness and then regain even more fitness. If you train again during this period of increased fitness, you will become even more fit the next time. Almost everything about this cycle will vary from person to person, but typically it takes 2 to 3 days after a workout to reach peak fitness, and that you can repeat this cycle about 10 times before your fitness stops increasing and plateaus. The next figure describes what is thought to go wrong when you overtrain:

The classic explanation is that overtraining results when a subsequent workout is attempted too soon, while fitness is still depressed. The notion is that, when you do this, each cycle is worse than the one before, not better. With all due respect to Runner Academy, it is my fervent belief that this explanation must be incorrect, or at the very least oversimplified. Here are the ways my experience differs from the above two graphs:

  1. Just prior to experiencing overtraining, my progress looks like the first figure, not the second. Training works fine at first but, without changing the workouts or the time between workouts, my performance declines precipitously, not gradually as shown in the second figure.
  2. If one estimates timelines on the second figure, onset of overtraining and recovery take about the same amount of time, about 10 days. For me, I go from performance increasing from workout to workout, as in the first graph, to a precipitous decline in fitness between one week and the next. However, return to baseline fitness takes at least a month.
  3. If it were true that overtraining results simply from damaging muscle faster than they can be repaired, then training would simply be about damaging muscle at this fastest rate. This would lead to an optimal level of fitness that could be maintained indefinitely. What virtually every modern training book acknowledges is that this is not the case, all of periodized training is based on this not being the case, and this is very much not my experience. Rather, it is very easy to reach a level of fitness that cannot be sustained. Having reached that level of fitness and won a race or completed a brevet, you must then rest before striving for that level of fitness again.
All of the above implies that there is something other than the maximum rate of muscle repair that becomes limiting when you train for months. One explanation for this commonly given in the exercise community is adrenal fatigue; that the adrenal gland becomes exhausted and is unable to produce adequate levels of hormones. As readers of this blog know, I am a card carrying member of the medical establishment, and the medical establishment firmly rejects this hypothesis. That said, it does have the advantage of better explaining overtraining, and so even if adrenal fatigue is incorrect, then any alternative explanation must involve something similar.

Even though I have no credentials as a coach, I am going to offer a speculative explanation for overtraining. To that end, let me start with a result from animal studies. It is known that you can take half the blood from a rabbit without killing it, it will recover and be perfectly healthy afterwards. In fact, if you take half the rabbit's blood on Monday, you can do the same again on Tuesday. However, if you try it again on Wednesday, the rabbit will die. The reason is that the rabbit has "stem cells" that it can use to regenerate half its blood in a single day. However, once these stem cells are so used, it takes many weeks for them to regenerate. I wonder if, in successive cycles of super-compensation, I am using up muscle stem cells, and that once these stem cells are exhausted, I cannot recover from training until those stem cells have been replaced. As we get older, we lose the ability to replace stem cells, which would explain why training is so much harder for me today than it was 40 years ago. Of course, this is just wild speculation with no experiments whatsoever to back it up, but it is an idea I find intriguing.

Despite being rejected by the medical establishment, the adrenal fatigue hypothesis explains more than my stem cell hypothesis. To explain why, I need to describe one final piece of the puzzle; that things other than cycling affect cycling performance. If I am ill or stressed at work or worried about something, my ability to train is reduced; I overtrain sooner and respond less well to exercise. Thus, there must be some global reservoir of energy in our bodies that is shared by everything we do. We can deploy that energy for training, for work, to deal with problems at home, or to fight off an infection, but energy deployed for one purpose is no longer available for others. As a member of the medical establishment, I do not believe that the reservoir of energy is the adrenal gland, but I do have to say that some such reservoir must exist.

I remain puzzled about the underlying causes of fatigue, especially the long-term fatigue associated with overtraining. Fortunately, I think my ignorance is of little practical consequence. So long as I rest when fatigued, I think I can avoid the consequences of overtraining, even without understanding its cause. Just over a year ago, there was an interesting discussion on this blog about the "Recovery Based Training" approach developed by Iron Rider. Iron Rider has found that he can use changes in his resting heart rate to guide him as to when to train and when to rest. I have not been able to use my resting heart rate for this purpose, it does not change depending on my level of fatigue the way his does. However, I have been using other measures of fatigue; persistent muscle tiredness, being unusually grumpy, and disappointing performances during training; for the same purpose. I have been trying to pay close attention to my level of fatigue and moderate my exercise accordingly. I feel like this has been helpful, but have not been doing it long enough to be sure. I will be reporting on my experiences in future posts, so stay tuned.