gsmacleod - 2011-05-14 5:46 AM Not accurate at all. For athletes that are trying to track caloric expenditure, I suggest the following calculations as a staarting point and then watch what happens with your weight based on intake and training load. Swim - 100Cal/400m Bike - .35Cal/kgkm Run - 1Cal/kgkm Shane
Different units, but these are almost exactly the same as my estimates:
swim: 0.25 x yards
bike: 0.25 x miles x wt (lbs)
run: 0.75 x miles x wt (lbs)
I converted your formulas into mine as we're within ~2% for bike and run, while the swim remains off by the yard/meter factor, so about 10%.
Someone else asked about sourcing. For swim and run, I went to a bunch of those websites with tables for various speeds, effort levels, weight, etc. I dumped the tables into sport-specific excel tables and ran regression to solve for underlying relationship. I got ~90%+ r-squared with the simple stuff above.
Biking is a bit harder because it is more strongly non-linear. I saw estimates all over the place, but the one that sounded credible and matched my experience suggested the following:
10 mph -- 0.17 calories/pound
15 mph -- 0.2 calories/pound
20 mph -- 0.25 calories/pound
25 mph -- 0.3 calories/pound
30 mph -- 0.38 calories/pound
I've seen that chart attributed to Edward Coyle. Since I'm working to improve in the 15-20mph bucket I aspirationally give myself credit for 0.25.