Wednesday, April 16, 2014

Recovery Stories

From Joe Friel's Blog post of this April 2:

Q: Why should a runner resist the temptation to run day after day, with little or no breaks?

A: It always concerns me when someone tries to set a record of running some pre-determined number of days without a break. That's not good for either physical fitness or mental health. Typically, something bad is going to come of this.

But this advice is for runners and I am a cyclist. Perhaps it doesn't apply to me? Not so. In the introduction, Friel says:

The topic is a critical one for runners due to their propensity for injury. But recovery is also of great importance to athletes in other sports. 

Well, guess what I just did? I went 11 days without a rest day. Why would I do such a thing? Partly it was an experiment, and partly it was the vagaries of day to day life. I don't (yet) own an indoor trainer, I am insufficiently motivated to begin a ride in the pouring rain, and for the two days of the weekend that belong to my wife, I am never sure how much riding she will want to do. Knowing that, I hate to miss a ride when one is possible, worrying that I might then miss the next four or five due to circumstance. As it happened, for five days one week, every day was nice, so I rode 5 days straight. The following weekend, my wife chose to ride both Saturday and Sunday. The following week, Monday through Thursday were beautiful days and I continued to ride, resulting in eleven straight days of riding. The twelfth  day was also nice, but I could both feel the effects of fatigue subjectively as well as see them in my results, so I reluctantly chose not to ride on a perfectly nice morning. To make my point about circumstance, my wife then chose to skip riding both days of the weekend, giving me three days off when I was looking for one.

So that's the vagaries of life, what's the experiment? I am currently trying to figure out how my body responds to exercise and recovery. I had been collecting a lot of results suggesting that riding multiple days in a row, up to 5, is beneficial. The experiment was, "how far can I push that?" In my post "Stories We Tell Ourselves" I argue that such an experiment is very difficult to interpret; there are so many explanations one can give for any set of results, it's hard to know what to believe. With that warning in place, this post is my current story on days on and days off.

Bob Weinberg
My postdoctoral training advisor, Bob Weinberg, would get annoyed at those of his trainees who were too lazy to graph their data. To be fair, we didn't have computers to graph our data way back then, we had to use pencils and graph paper. So a lazy trainee would stare at the raw numbers from their experiment saying "I don't need to graph it, I can see the pattern." Bob would berate them until, with eyes rolled, they put pencil to graph paper, and, as often as not, their eyes would go from rolled to bugged as they realized that Bob was right, they had completely missed what their experiment was trying to tell them. The human brain understands pictures much better than it does numbers. So too with me and my training results. (You might have been wondering when I was going to get back to bicycles.) I always was a diligent grapher, even back in the pencil and paper days, and today, all my rides are graphed the day I complete them. That said, there are many ways to graph the same results, and figuring out what is going on sometimes depends on finding the best way to look at it.

I was first attracted to the MAF tests of Dr. Phillip Maffetone because he promised that they were good indicators of overtraining, something about which I worried a lot. Since I started riding them in 2012, I have not found that to be so true in general, but it seemed to be true last week. Note the four rides circled in red on the graph below:

Those were rides 8,9,10, and 11 in my unbroken series, and each was slower than the one before. This is very unusual! I have never seen rides with serially decreasing speeds like this, and there were no alternative explanations, such as increasing winds, for the decreases. What I usually see when I do rides 3 to 5 days in a row is that each ride is faster than the one the day before. This declining series, combined with my subjective feelings of fatigue, were what convinced me not to ride on Day 12. Based on this, I tentatively concluded that I need at least 1 rest day each week. However, when I looked carefully at the data in preparing this post, I noticed the previous 5 rides, circled in yellow. Although these were not decreasing, they were also not increasing.

One additional point: The black, straight line through all the blue points is the best fit line Excel draws; is is the average rate at which my speed is increasing or decreasing. The upward slope of this line indicates that my results are improving, but when I look at it closer, it looks like they were increasing faster at the beginning and then leveled off. To my eye, the "plateau" phase are the rides circled in green. What I then did was divide this into two separate graphs and had Excel fit the best straight line to each separately. First I plotted the rides outside the green circle, the ones I thought were improving:

Excel agrees they are improving, and at a rate of about 0.06 miles per hour per day. Over the 40 days of riding shown on this graph, my average speed increased by 2.4 miles per hour. I then plotted the rest of the data:

The line fit by Excel was almost perfectly flat. (Because it fell on top of the 15 miles per hour line on the graph, I highlighted it in purple to make it visible.) In summary, my original view of the data that my speed had been increasing at a rate of 0.02 miles per hour per day over the last 100 days is probably wrong. Rather, my speed increased at 0.06 miles per hour per day, from 12.6 miles per hour to 15 miles per hour over the first 40 days, and then has been varying around that average for the 60 days since. As all the experts would have told me, because I didn't change my training plan, I stopped improving.

How does this new theory on my training overall affect my thinking about the slow rides circled in red? What I think happens during this plateau phase is that if I take off a couple of days, I drop to the low end of the average, around 14 miles per hour (the first of the rides circled in green.) If I then ride for 3 to 5 days in a row, my speed will increase to somewhere between 15 and 16 miles per hour (the rides circled in green.) If I continue riding six days and taking off one day each week, I can keep my speed relatively constant in the 15 to 16 miles per hour range (the rides circled in yellow.) However, if I fail to take off at least that 1 day, my speed will drop despite my riding (the rides circled in red.) I do not consider these conclusions final, they are simply the stories I am telling myself today (my working hypotheses.) That said, they are totally unsurprising and I would bet they are correct.

What does this all mean in the big picture? It's way too early to say. I started my current training regimen at a time of despair when I realized that the cycling goals that had been driving me for four years were not attainable and that I needed a temporary training schedule that would keep me from abandoning cycling altogether. I picked daily MAF test rides because I had good experience with this schedule in the past and because it satisfies the healthy living exercise recommendations of the American College of Sports Medicine. I hoped this schedule would keep me healthy and give me a base from which I could build in the future. Over the last few years, I had developed the impression that I need at least one rest day a week, and my experiment confirms that. Recently, I have been feeling that it is time to change my training routine, and looking at the data confirms that as well. All I need to do is figure out a training plan to which to change and build up enough enthusiasm to actually make that change. Stay tuned.

No comments:

Post a Comment