I have determined that when I swim, based on my heart rate, I am burning an enormous amount of calories. The other day, I wore my HR monitor and based on my average HR, time spent swimming, and my weight, I burned 1053 calories. Now, the next day, I ran for 40 minutes and burned 453 calories.
I have noticed that when I just swim over a number of weeks, my LDL cholesterol readings go up and my body fat goes up as well. When I just run and don't burn as many calories (according to my HR monitor) my LDL drops, my HDLs go up, and my body fat decreases. I've noticed this now over the course of 13 years.
Anybody know of any studies out there that might explain this? Why would an activity such as swimming that obviously burns a bunch of calories cause an increase in body fat?
Chris - I agree with you somewhat on the calories explaination. The only thing that perplexes me is that in college as an 18-20 year old, I probably trained in swimming 15-18 hours a week. Even with all those hours of training, I still had to be mindful of my diet. In my mid-thirties, I trained only 12-15 hours a week for triathlons and could barely eat enough to keep my weight and body fat appropriate for my height and frame. It was bad enough that I wake up in the middle of the night starving and have to eat something.
I seem to recall reading once about a study of elite-level swimmers and runners. The investigators were puzzled by the fact that the swimmers tended to have higher body fat percentages than the runners (although both groups were quite low, as you might imagine).
Unfortunately I cannot find the article now but I seem to recall that the swimmers' appetites were generally greater than the runners -- they tended to want to eat more (relative to workload). After hearing about Phelps' routine daily diet, I guess I don't find that hard to believe...
Of course, it may well be that low body fat favors running as a sport more than swimming, so there is a self-selection problem going on here (ie, the elite runners are those people who tend toward lower body fat).
Chris - I agree with you somewhat on the calories explaination. The only thing that perplexes me is that in college as an 18-20 year old, I probably trained in swimming 15-18 hours a week. Even with all those hours of training, I still had to be mindful of my diet. In my mid-thirties, I trained only 12-15 hours a week for triathlons and could barely eat enough to keep my weight and body fat appropriate for my height and frame. It was bad enough that I wake up in the middle of the night starving and have to eat something.
I seem to recall reading once about a study of elite-level swimmers and runners. The investigators were puzzled by the fact that the swimmers tended to have higher body fat percentages than the runners (although both groups were quite low, as you might imagine).
Unfortunately I cannot find the article now but I seem to recall that the swimmers' appetites were generally greater than the runners -- they tended to want to eat more (relative to workload). After hearing about Phelps' routine daily diet, I guess I don't find that hard to believe...
Of course, it may well be that low body fat favors running as a sport more than swimming, so there is a self-selection problem going on here (ie, the elite runners are those people who tend toward lower body fat).
