How much faster do you get by losing 10 lbs? (Read 2053 times)

well....I lost a bunch and I am definitely faster.....but I also train better so who knows. But I think my training this last year post baby is about the same as it was the year before I got pg and I am about 15 lbs lighter and about 45 seconds/mile faster depending on the length of the run. So pretty close to the 3 seconds/lb predicted. Mostly I just get injured less, and my feet dont hurt running long runs. For the opposite test, I ran through my last pregnancy and I swear to god I could feel each pound on my legs in a hurry. But I suppose you could blame some of the slow down on "other factors". But every time I had a 2lb gain in a week I slowed down another notch. However - I will say that running through a pregnancy does wonders for your hill running. The secret to great hill running: Run consistantly while gaining 40 lbs, then lose 55...really builds the legs. Purely subjective of course.

You'll know your getting close to your fighting weight when people start telling you to eat a sandwich.

Yeah, the "You're too thin, you need to stop running so much" line is also a good indicator. Obviously, these poor souls haven't seen me naked...

How about reversing the question and say, how much slower do you get by gaining weight?... it may be difficult to get an accurate #. It would probably help if anyone wishing to try this experiment uses a heart monitor, that way we can be totally objective. For this test, take (1) 20 lb. dumbell plate and find a way to secure it to your upper body. Go for a 5 mile run. Record your time. Subtract the difference of what you would normally run that distance / heart rate and there it is.

How about just using dumbbells for the test? One might have to repeat the test a few times (with and without) to make sure the "noise level" from other variables isn't too high. Go to a track (e.g.), warm up, run a given distance at a given heart rate without the dumbbells and record the time. Same thing with the dumbbells. Or maybe 1.5 miles without, 1.5 miles with, 1.5 miles without... all at the same HR. I used to run with 3 lb dumbbells all the time, and it got so that I didn't even notice them. That 6 lbs was about 4% body weight. Never could get used to the 5 lb ones so that I didn't notice them, though. If you do some of your weekly runs with dumbbells, you won't notice your shoulder muscles getting tired towards the end of a marathon anymore

Here's a calculator for such a thing, assuming no change in fitness (which is usually not the case -- usually weight loss is accompanied by improved fitness/conditioning).

Actually, the formula is quite accurate, though (as mentioned) it's difficult to isolate the fat variable, since training tends to change at the same time. Basically, you multiply VDOT by Initial Weight/Final Weight (in Kilos). This will give you your new VDOT. Since VO2Max is an averaged by mass, losing weight will increase your VO2Max, provided you don't lose functional muscle mass, which could affect the numerator.

I've got a naive question. I've seen a couple hardcore women in my area, hardcore as in bodies so slim, they look like tiny, breakable birds, though I realize they're at great "fighting" weight for a runner. Am I wrong to suspect that someone with so little bodyfat might have a weaker immune system then if they had a little more weight on them? On one hand, they gotta be tough because they're getting out there for huge mileage, but I wonder how they manage it when they look almost sickly. Am I basing too much on appearances?

Nobody has anything to say to Girl in Motion's comment? I remember Arthur Lydiard saying that, if you have body fat less than 5%, you might (not "will" but "might") run in a risk of "hitting the wall' in the marahton. Yes, I know our body has enough fat inside the body, not just subcutanuously, but still, after we run out of glycogen, and there is a limit to how much glycogen we can store in our body if I recall it correctly... Actually, my first reaction to this thread and all the replies is that I just hope some young teenage competitior, unfortunately more girls than boys, don't read this thread and get encouraged wrongly and start to go crazy about losing weight... Like someone else said (a few of them, I thought...), there's a better way to be a better runner than simply losing weight (like has anybody heard a word "training"?). In order to train well, you need energy. Losing body fat or excess weight is fine; but not eating to achieve that is not the way to go about. Has anybody read about the Olympic marathon champion, Naoko Takahashi, gubbling down 50 pieces of sushi? Besides uncooked fish, that's a lot of rice! That's what you can do if you run 70km a day...or she can run that much because she eats that much???

It depends on if you're talking about women or men. 10% is about where elite females are. Elite males are closer to 5%. They pretty much look the same. By the way, you're right to worry about young athletes and their eating habits. A huge percentage of female collegiate runners has anorexia. The problem is that they get positive feedback for a while: times keep dropping, so they keep starving themselves, until they get sick and injured.

Thanks for addressing the question, Nobby! It was funny, after I asked that, I saw Spirit Of The Marathon and man, Deena Kastor was soooo thin, and I know she has to be strong to be pulling in all those miles, but it seems like someone that skinny would more open to catching something as simple as the flu more than a normal weight person would.

Double funny you mention that... I remember watching that particular Chicago marathon and thought how skinny Deena looked. I thought a part of it could be what she was wearing... But I remember thinking if she could hold on to the wire. Lo and behold, it was so darn close! Elite runners are playing with a dynamite. They've got to train hard and with training comes "getting skinny"! It might be okay if you're competing a 5k or 10k (I'm talking here about being an elite and being lazer fast). But a marathon could be a bit different. I remember when Naoko Takahashi, then the defending Olympic champion from 2000, lined up at the Tokyo Women's Marathon in 2003; I couldn't believe how skinny she looked--I mean, you could see shadow on her cheeks (in her face, that is!). I seriuosly doubted if she could hold on till the finish. She took off very fast--and this is what could happen; when you are that skinny, you feel FAST. At the start of the marathon, you want to feel a bit heavy, somewhat, what we call, "90% ready coming up." She slowed badly and finished second and lost her spot on the Olympic team. Not too many people talk about it in this country; I don't know if it's praised to be skinny... I remember watching 1991 World Championship men's marathon; it was held in Japan and one of the local favorites was Takeyuki Nakayama. He's a tall skinny guy to beging with; but the commentator (it could have been Seko) said something about him being too skinny. He dropped out at half way. I don't know if there has been any "research" done on this; and I know some people stay skeptic until it's proven in the lab; but it's more or less, as far as I'm concerned, an intuitive sort of things. A good coach with experienced eyes can tell. Another issue with, particularly women, losing too much weight is skipping periods (I guess it has to be "particularly for women"; if that happens with a guy, that wuold be weird...). I know it happens and it's not that big of a deal...to a point. There's some sort of mechanism (and I can't remember exactly how...I have an article somewhere but I'm not going to dig it out) that links missing period to losing calsium which leads to weak bone which leads to stress fracture. I remember about this elite female athlete locally; someone said she looked awfully skinny and I mentioned about possibility of stress fracture. Within a couple of days, she was diagnosed with stress fracture... Okay, that was more of a coincidence. But I've actually seen more than a couple of insidences, having been a women's team coach, that I'd be VERY careful about the issue. Losing weight is something that happens as you train more. And, coupled with increased training, you'll get faster. Yes, losing excess weight WILL make you faster--it requires 0.71ml of oxygen to move 1kg of body weight every meter. So if you are carrying more (kilogram of body weight), it requres more oxygen to run. But that should NEVER be an objective to become faster. There are too many other things that could come along with it that we probably don't even know about. Lose weight to become faster is like tampering; it should happen naturally AS A RESULT.