When backing way off from a heavy training workload, body weight can rise 2/3/4 even 5 pounds—this is the body taking on glycogen, which requires 3 parts water for every pound of glycogen.
Maximizing stored glycogen is not just energy storage; it is a sort of “camel’s hump” water storage system for long duration events, so it is generally a benefit in avoiding dehydration.
According to Wikipedia, a human body of 70 kg can store up to 120 grams of glycogen in the liver, and another 400 grams in muscle tissue — 500 grams. The discussion is absurdly general: is that 5% or 30% body fat and is it a couch potato body or a trained athlete? Very poorly articulated. Ditto for NIH.
I weigh about 77 kilograms /170 pounds when about 7% body fat. Taking the Wikipedia figures, I will assume 132 + 440 = 572 grams of glycogen (10% more body mass).
Storing 572 grams of glycogen implies storing 572 X 3 grams of water with it, for a total of 572 X 4 = 2288 grams / 5.0 pounds of stored glycogen in its water matrix. This figure corresponds very closely to my own estimates based on reduction in body mass after long events or training rides (accounting also for hydration).
Assuming 2500 calories of glycogen (rough estimate), this translate to about 653 kilojoules at 25% efficiency (if all muscular effort were from glycogen)—less than an hour of cycling at my double century pace. Of course the body does not do that—fat is burned up to the limits of physiology, including available oxygen.
My own experience suggests that I can burn off my glycogen over 3 hours or so at a moderately hard pace as the result of years of intensive training—much of the energy comes from fat, thus preserving the glycogen. But it is mandatory to take in a steady supply of a product like GU or Hammer Gel at 200 calories per hour or so—or you’re hosed in a double century. Failure to do so means misery by mile 120.
This might be premature, since I am expecting a further drop in body weight (body fat), but since I have to start tapering in about 3 days for the Feb 17 Camino real double century and the awesome summer-in-February weather might change, I thought I’d share and explain how weight (fat) loss occurs—sometimes in frustrating and confounding ways.
I weigh myself each morning on scale accurate and precise to 0.1 lb—without clothes after waking up and after the bathroom. It’s no good to eat and then weigh, or weigh with clothes on (an idiotic practice at doctor’s offices, which have indicated that at 10% body fat that I am borderline obese).
I also track food intake by the gram and total it each day along with my calorie expenditure according to the SRM power meter. This gives me a daily caloric deficit. While there can be some measure of error (mixed foods, losses from digestion, etc), it is far, far more accurate than moronic “serving size” figures for an “average” avocado or banana or whatever. In general caloric intake from food is overestimated, since it takes energy to digest many foods and energy to repair and build muscles.
About the graph below
Below, I started out at around 190 pounds in late December. Having some illness and traveling right after New year’s for 5 days, I had little or no exercise.
So the training really starts around Jan 7 2018. Which means that I have shed at least 13 pounds of body mass in 4 weeks (3.2 pounds per week). The 30-day caloric deficit line (dark orange) shows about 1256 calorie per day caloric deficit.
1256 calories * 30 / 3500 calories per pound of body fat = 10.7 pounds of body fat
Which is in line with the 13 pound drop in body weight—recovery and muscle growth and digestion losses chew up a lot of calories.
Note the early February green diamond weight points at far right, which for 6 days hover at around 179.5 pounds. This timeframe was during the outrageous 7-day goal I set for losing 4 pounds of body fat. All that effort (17000 calorie deficit) and weight stays the same?! Not really—this is the body adapting and recovering which means holding onto fluid in the muscles and gut. Always let a few days pass, and this is why daily weigh-in is a key psychological tool.
See how starting Feb 6 (4th green diamond from right), body weight starts to drop, then plummets—the body gives up the extra fluid and the numbers are back in line with the computation of fat loss from caloric deficit. This is typical of physiological behavior after hard workout(s) that stresses the body beyond what it is used to. What level of glycogen is present is hard to say, but the steady workload means that the numbers are consistent day by day, since there is no significant backing off from mid-January onwards.
- On the right, the vertical axis shows the day’s caloric deficit and the green axis shows body weight.
- The 7 day (light pink), 14 day (light orange) and 30-day (red-orange) caloric deficit lines show that for 30 days I have averaged a caloric deficit of about 1256 calories per day which is about 0.36 pounds of body fat per day, that is, 2.5 pounds of body fat per week. That trend accelerates hugely in late January, when my body acquired enough fitness and resilience to take a serious training “beating”.
Graph showing body weight and caloric deficit per day
Based on trends, I expect weight to drop down to the 173 pound range by Feb 13 or so.
My goal is 164 pounds, which is what I weighed in high school. At my goal of 165 pounds, I should have about 5.3% body fat in theory although muscle loss can also occur (2011-09-13 showed 7.9% body fat at 173.7 pounds), start to look gaunt, outclimb almost everyone and yet have the power to push through the flats and headwinds far more powerfully than the skinny and lighter guys. It will be very difficult to get to 165; the body fights back (to avoid starvation) and non-linear effects occur (metabolism, hunger, fat vs muscle loss).
- For climbing, it is all about power to weight ratio. Weight means total riding weight (TRW)—body weight plus bike weight plus food and clothing and so on. One pound less for a TRW of 184 instead of 185 means climbing speed on steep climbs should be about 1% faster. Not much? That’s 1.2 minutes on a two hour climb—the difference between first place and 5th place for top competitors. So contrary to silly assertions that defy the laws of physics, once you “lean out”, every pound count, particularly for lighter riders.
- For flats and headwinds, it is all about absolute power. Here, the big guys (or gals) win—with surface area not much different between riders, whoever can produce the most absolute power goes faster.
Assuming climbing at 280 watts average, power-to-weight would increase from (280/173.7) = 1.61 to (280/165) = 1.7. That’s 5.6% faster. Let’s assume a steep climb so most of that goes into climbing: 5% faster on a 120 minute climb means a 6-minute reduction, which means “bye bye” to most all riders. Consider that the 54000 vertical feet of climbing (approx) in the 2018 California Triple Crown means somewhere around 24 hours of climbing (8 hours per event), and the savings can be estimated very roughly at 24*60*.05 = 72 minutes. That’s top placement versus merely fast.
I have the intermediate build such that when really lean I can climb really fast (power to weight), and when it is flats and headwinds, all the more powerful riders (absolute power) are 15 minutes behind, still climbing—they may be putting out another 40 watts, but body weight just kills the climbing speed.
Double centuries are an ideal event for me when there is a moderate mix of climbing and flats. I welcome a headwind, because 90% of other riders cannot generate as much power as I can (this is not bragging, but observation as a matter of fact after 34 double centuries). But if I can lean-out, then at 165 to 168 or so my climbing speed is right up there with all but a handful of riders of similar age (again, experience).
So goes the theory and my hopes of winning some double centuries this year—but it is hard to compete with 30 to 60 minutes of time reduction from a massive workload reduction by hardly efforting most of the distance via drafting, so we’ll see if Chuck Bramwell agrees to my proposal.
The day after an amazing 82 mile ride which was after a 35 mile recovery ride which was after an 85 mile ride which followed losing 4 pounds of fat in a week, I did a 49 mile recovery workout, odd as that may seem—49 miles in a bit over 3 hours.
Setting out, I was flabbergasted that I could feel no soreness after the prior day’s 82-mile tough workout. A bit of quadriceps soreness did develop in the left quad, but I had to tense the muscle to feel it. What does this mean? Superb recovery—I guess my diet is working well, and also the Marc Pro. I feel 6 years younger and I mean that—in the space of a few weeks. No better Christmas present is possible (well, I have a bit more imagination than that, but it is almost true).
The very satisfying thing (have you felt it?) is doing a workout, even a recovery workout, and feeling just terrific as if there were some feel-good drug coursing through the system. But it is not so—it must be endorphins, or that 2011/2012 “everything hitting on all cylinders” thing that is incredibly satisfying.
2018-02-09: 3 hour and 49 mile recovery ride