Posted: 03/07/2013 at 11:26
I'm a bit sceptical of these "2 seconds per mile per pound lost" figures that are often quoted. There are two effects of losing weight that have to be taken into account, and they need to be thought of seperately.
- If you could "simply" lose the weight instantaniously, then I guess 2 second a pound seems reasonable, simply by carrying less lumber around.
- But a second effect is how you go about losing the weight: if you do it by more intensive training then your weight might drop, but you will be much fitter.
This second effect is more difficult to assess, and will all depend where you start from in terms of base fitness. Many people report, for example, completing a 16 week marathon training plan without losing any weight at all, but feeling much fitter, and running much faster. I would have thought this second effect is likely to exceed any effect of simple weight loss.
So the relationship between weight, fitness and speed is complex. Or in other words, I don't know!