The reason I ask is that Mon-Fri I run home from work with a 10 pound backpack and am wondering how to adjust my training paces for the extra weight.
As an example lets say I am suppose to train today at a 8 min/mile pace and I will be doing it with the extra 10 pounds. Should I keep to the 8 min/mile pace or should it be adjusted because of the extra weight? If I should adjust the pace by how much should it be adjusted?
Does anyone have any info on the affect of weight on running pace? Should I just suck it up and test with and without the extra weight to get two sets of numbers or is there a formula I could use?
Just make sure that those 10 pounds are evenly distributed and that you aren’t top heavy. Better still try and get as much of the weight around your hip area. And even better, ensure you have a REALLY good knapsack designed for running/long hikes. That added weight, not properly distributed can play havoc on your knees/back and shoulders.
I do all of the above. I have been doing it for the past 6 months or so with no problems.
The reason the quesiton comes up now is that before i was mainly training based on HR and now i am focusing more on pace. Just trying to figure out how it is affected. I am thinking about 30 sec/mile.
I have heard that it is 1 sec/mile for every 2 pounds. So in your case that 8:00 min/mile pace would be 8:05 for the same effort.
There’s been a few threads on this and my estimate has always been more like 2.5 sec/lb/mile but that’s for body weight which may be a higher number because of the metabolic cost of keeping that weight alive, (fat cells etc. not water weight) so added dead weight to the body probably costs less but I’ll bet it’s more than 1/2 sec/lb/mile.
If you search, you’ll find that this topic has been discussed many times before.
That said… I’ve found that the rule of thumb which says “a given percentage gain/loss in weight will result in the same percentage gain/loss in pace, all other things being equal” holds very well for me, at least over a 10-15 pound range.
If you search, you’ll find that this topic has been discussed many times before.
That said… I’ve found that the rule of thumb which says “a given percentage gain/loss in weight will result in the same percentage gain/loss in pace, all other things being equal” holds very well for me, at least over a 10-15 pound range.
The percentage thing seems to make sense to me. I am 160lbs so it is about a 6% incrase in weight so that would be about a 28 second affect per mile.
Oh , it wasn’t me that remembered… GMAIL NEVER FORGETS!
I remembered that the same day I read your post, I happened to quote it in an email to a friend that was asking about running efficiency… or was that economy… oh shit, what a can of worms.
The crude rule of thumb that came directly from Jack Daniel’s (the running coach/exercise physiologist - not the drink) is 2 seconds for every pound of weight; 20s/mi for every 10lbs. Of course that will not hold true if you are a freak of nature and are dipping too low to where it compromises performance. Of course if you are adding weights the distribution might cause it to impact your running mechanics some and it could be worse but unlikely less than that.
A guy in my n’hood “runs” with a lead vest. I asked him about it and he says its like a batter swinging a weighted bat before stepping to the plate. So maaayyyybe, you’ll run faster than 8’ miles by training “heavy”.
I have decided to adopt this approach in the off-season, but I will use a more “natural” approach to ensure a thorough and even spread of the desirable load. To this end, Krispy Kreme and Dominos will be seeing a marked uptick in their local business.
Sorry for the slow response. Initialy I would not had thought it would be related to what distance, but it is supposed to be roughly independent of the distance. I am certain, however that it gets worse the farther you go if you are not well trained at the longer distances. That calculation that was quoted above is interesting - I’d have to look it over more to see where that comes from. I originally was just taking the VDOT tables from Jack’s book and adjusting the VDOT for weight change as he describes for when one gets injured or sick (Essentially just multiply VDOT by the lower weigth devided by the higher weight times the VDOT -if you are projecting what a loss of weight would correspond to). You then get the adjusted VDOT and can see what paces for the different distances the new VDOT would give. When I corresponded with him, he said yeah that works but its about 2s/lb. If you have his book you can do that, but I think it is just an approximation. I’ll take his word for it. More importantly it is a lot more than most would think. The main thing is it is weght loss that does not impact your strength, hence without losing muscle mass. The majority of us, however have a few pounds we could shed and improve performance. There is a minority, however, that would suffer from weight loss where this would not apply.
