21 December 2009

Strength to Weight Ratio: Does Weight Training Make Me Slower? Pt. Deux

In her article for Ironman.com, Jennifer Hutchison—who has a dossier a mile long that includes being a 9-time Ironman finisher, Board Certified Dietetics, and a USA Triathlon Certified Level 3 Elite Coach—defines strength to weight ratio this way:

"Simply defined, strength to weight ratio is the measure of a person’s strength divided by their body weight. When comparing two individuals who can generate similar amounts of strength, like reaching the top of a bike climb together, the person who has a lower body weight will have a higher strength to weight ratio. If the heavier rider, carrying more body weight (body fat) up the hill, exerts 100per cent effort in the climb, then his leaner counterpart should complete the climb with less effort. The leaner athlete, with the higher strength to weight ratio, will be over the hill and gone in no time when he or she increases their effort to 100 per cent."

I am not quite sure that I understand Ms. Hutchison's relationship of body weight to more fat, and I am not suggesting that she is incorrect, I just need some clarification. Body weight does not necessarily translate to more fat. It could mean that one athlete has more muscle density than the other. Muscle density is 1.06 g/ml and fat density is (about) 0.9 g/ml. Thus, one liter of muscle would weight 1.06 kg and one liter of fat would weight 0.9 kg. In other 
words, muscle is about 18% more dense than fat. Currently, I am 6'2, 180 pounds (81.8 kg.) My training partner Adam is ten to twelve pounds lighter than I am (and about an inch and a half shorter,) but my body fat percentage is still lower than his. What about sport specific training and an athletes cardiovascular fitness/VO2 levels as well? If both athletes have identical body types, one might still have a genetic predisposition to perform better. 

All I know, is that we are ultimately our own best coach. Don't get me wrong, I believe in coaching, for sure! But, I recommend that the individual athlete make an inventory of their performance based on the physiological differences that they encounter as a result of their strength training, and/or sport specific training. This is information that should be vital to your coach in helping them to determine your dietary needs, and strength training routine. 

Here are wifey and me this summer in Maine. This picture was taken about two weeks following the Musselman Half Ironman. I weighed in at 177 pounds race morning—the thinnest I've been since my freshmen year of college. The weeks immediately following the half, I was running the fastest I ever have, setting new PR's consistently. The only downside—if you can call it one—is that I had to eat constantly in order to maintain my weight, or I would have shriveled down. There were times on my rides when I felt that I did not have enough solid food in me to fuel the long rides. Ah, it is great fun learning how to balance it all. I am hoping for a more successful race season in 2010 based on the knowledge of strength and condition I gained this past season. 


Vertical Man said...

The strength-to-weight equation mystifies me too. I remember doing the Horribly Hilly Hundreds ride a few years ago and getting out-climbed by lots of "large" riders. On that day at least, my slight build seemed to be a distinct disadvantage.

Mark said...

Vertical Man, I hear you. One of the deceiving things about triathlon, or endurance events in general, is that you can not judge someone's cardiovascular fitness by looking at them. I hate to say it, but I also use to size up my competition—excuse the pun—and think, "There is no way this big dude is going to hang with me on the swim/bike/run," only to be passed somewhere along the course by some clydesdale. Strength to weight ratio is important, but perhaps less important than an athletes overall cardiovascular strength.