Wight loss and performance in sprints?

[runjumpleah]

a coach told me that if you lose 10lbs you will decrease your 100m by 1 sec. This was supposed to have been determined in the 80's i was wondering if someone knows where I could find the information that "supports" this

[gh]

Re: Wight loss and performance in sprints?

I believe that's Chapter 113 of Mother Goose (either that or 121 of The Brothers Grimm).

[Class Clown]

Re: Wight loss and performance in sprints?

My doctor tells me I'm 100 pounds overweight, but after learning this I finally have motivation to lose weight. A year from now I'll be a svelte 130 and by far the world's fastest man, running 5-flat as I will be.

[abinferno]

Re: Wight loss and performance in sprints?

Pretty sure you won't find any substantiation of that claim. Think of the physical limits involved. If you lost too much weight, you won't have muscle to run fast anymore. If someone weighs 300lbs and drops to 290lbs, are they gonna drop a second on their hundred? No, if they run far enough, they might drop dead from a heart attack.

[Leo62]

Re: Wight loss and performance in sprints?

Brilliant!

[Cerutty Boy]

Re: Wight loss and performance in sprints?

Runner's World often cited a 2 second per pound per mile rule for distance running. Peter Coe (Better Training for Distance Runners) has a metric formula, but I have never bothered to see if the same relationship is predicted (as the RW formula). Of course, this is not what you were looking for anyway...

[runjumpleah]

Re: Wight loss and performance in sprints?

no crap you would lose muscle the point was to make sure his claim was false he is a nationaly recognized division one coach who said it

[Asterix]

Re: Wight loss and performance in sprints?

> the point was to make sure his claim was false

So what, exactly, was his claim?

Was it that the formula of 1 second per 10 pounds of body weight dropped applied universally to everyone?

Or was he referring to a specific athlete at a specific time (say, early season and the sprinter is out of shape and overweight)?

The first is obviously farcical, while the second appears to be entirely reasonable.

[eldrick]

Re: Wight loss and performance in sprints?

we have discussed this IAAF BB before.

simple physics tells you that if you have a loss in wt.,but same power output, you will become quicker (sensible parameters)

consider a 75kg guy who runs 10s. his average power output for that race = energy/sec is

0.5*m*v^2 = 0.5* 75* (100/10)^2 = 3750 W

(compare this to a fan-heater)

now, consider he loses 1kg in wt., but crucially, maintains same power output

then

3750 = 0.5* 74* v^2

where v turns out to be 10.06m/s & his 100m time becomes

9.93s

therefore, roughly for peak athletes, a drop in wt. of 1 lb would make them 0.03 - 0.04s quicker, with the all important proviso, that the loss in wt. is not a loss in muscle & therefore power.

the trouble is with this, is that the top guys are so finely tuned & at their peak, it is virtually impossible for them to lose any wt. & still maintain the power

[gh]

Re: Wight loss and performance in sprints?

Then, of course, it also seems true that adding muscle weight can make you faster. Viz the 10.00 Carl Lewis who was 170 in '81, vs. the 9.91 Lewis who was 175 a decade later.

[Powell]

Re: Wight loss and performance in sprints?

If my weight drops down to zero, I'll be able to run 100 meters in negative 5 seconds... pretty good :-O