Weight and Marathon Time

I did that experiment two years ago running half. At 51 weighting 184 I finished half marathon in 1:41. One year later, after slowly loosing 28 pounds, I run the same course 1:26. I did similar 10 week half marathon training running 5 days a week averaging 35-45 miles per week

since than i gained 10 pounds and dropped al little in average pace numbers

It's true that combination of losing weight and improved running fitness helped to drop time. When I started I was mostly riding bike and could barely run 5-6 miles without killing myself. Now I can go for a 1.5-2 hours run just because i feel like that

I am thinking to test that theory again. This time my running fitness level should be about the same and I can drop up to 15 pounds. I don't expect the similar time drop this time tho. If I don't drop much time it still should be much easier to run race with fewer pounds to carry

Thanks all for the advice, as well as encouragement.

There's a lot to take into account - I'm going with a lower carb (under 100g a day) whole food diet, no alcohol, and supplementing amino acids, potassium, magnesium, as well as whey protein.

I want to be as objective in this experiment as possible - will likely get body fat % and a VO2Max test completed in short time.

I'm targeting an a fall marathon - 16 or so weeks. Every 2 weeks I'll have some sort of time trial and weigh-in. I'll slowly increase mileage from my current baseline of around 50mpw.

One piece that is encouraging (in a sense), the last 7 weeks leading up to the sub-3 hour marathon week were only 25 miles per week. The average for 12 weeks leading up to the week of the marathon week was 32 miles per week. So that's even lower mileage than I thought. I'm also 33 years old, and began running regularly at 30 years old.

I'll also share my progress via a blog for anyone interested in the coming weeks. I would suppose there are some others in similar kind of camps with this kind of thing. Thanks again.

You won't run 2:34 in the fall. You need to get to 150 and train there for it to count.

I set my marathon PR at 5' 7" at 127. Now at 162 I'm running 30 minutes slower because I can't handle the mileage or the pace without sucking wind.

I don't like how you picked 150 out of thin air. 155 or 160 might be more realistic targets. IF you get down to 150, if anything I expect you to go a little faster.

1:41 vDot of 44 at 184 lbs

1:26 vDot of 53 at 156 lbs

Formula Predicts : 184 / 156 x 44 = 52.89 vDot which is about a 1:26 half!

I'll add that I know of a guy who's 5'10", 183 and has gone from 3:11 to 2:37 without losing a pound - so it can definitely be done. He runs 60-80 mpw and eats a TON while doing quite a bit of upper body lifting to maintain his weight...

Small world, I'm the exact same height and weight and ran a 2.59 a couple of weeks ago

Bump.

I just wanted to +1 the observation that weight doesn't just "auto-correct" for everyone to an ideal point when you just increase training volume.

I'm 6' tall and my ideal race weight seems to be about 160, or a few pounds lighter, when I'm glycogen loaded and hydrated, ready to run a marathon. This might mean I weigh in as low as 152 or so if I'm depleted and dehydrated after a long workout while cutting weight. If eat the same foods and maintain the same diet I use to reach this weight, but just eat an amount that I decide intuitively, I will sit at about 170, even running 70+ mpw consistently for months. I have to actively pay a little attention to the number of calories I'm taking in and enforce at least a small deficit, occasionally sustaining hunger, to get to my ideal weight.

On a side note, I'm not entirely convinced of rules of thumb for performance improvement with weight loss. I've lost 15 lbs in 10 weeks before leading into a marathon training block while hitting decent training and I can tell you I did not see the predicted changes in my running paces. I've also gradually put on 10 lbs during training while not tracking calories and actually been running faster than at the start of the training block. Of course it makes sense that being leaner must physically be better, but I don't think it's right to expect to drop so much time by just cutting weight.

How did the race go? Were you able to get to 150lbs? Did you run faster?