Does Weight Gain Affect Running? (Should runners be skinny?)

[00:00] If you’ve been to any running event ever, you probably noticed that generally speaking, all runners in these groups are relatively thin, right? Or at least the ones that perform very well. And this lends itself to the idea, the must be skinny to run fast. Is there any truth to that? Well, I’m Jesse Funk. Today’s episode of Runner’s High, we’re going to talk about how does weight affect your running speed, and does gaining weight make you run any slower?

[00:44] This is kind of a hot button topic for me because although I had not struggled with issues of the scale itself, I know that weight can be a very touchy subject for a lot of people. And I mean that in a polite way, in the sense that it can be a big issue for someone who’s having trouble with body image issues, or feeling like they need to be skinnier, or prettier, or more handsome, or whatever.

[01:17] There are a lot of messages that we receive from the media, from articles, from publications, from people like me here on YouTube telling you what to do, what to think, that say you should be this or be that or need to do this or that. And it feeds into our own hopes, desires, fears, and those kind of things. So, this is meant to be a hopefully, honest discussion about the effects of weight, weight gain, weight loss, and how it fits into your running performance.

[01:48] Now, if you do any googling on this, kind of like I did, just as a precursor to see what other people are saying about this topic, you will probably come across these studies that have been done that basically say, for every pound gained or lost, that you improve or make your time slower two seconds per pound per mile. So, if I lost 10 pounds, then supposedly I would be 20 seconds per mile faster than my present weight.

[02:24] Now, this is all well and good. The efficacy of these studies is accurate in the sense that they do produce significant results. But the studies themselves are flawed. And the flaw in these studies is that they can’t measure things accurately in how we actually train and become faster runners.

What these studies do is they take say you and I were part of this participant group. And we set a benchmark speed by ourselves, right, just as we are. They take our weight and then one of two things happens depending on which study you’re looking at. Either and more commonly, they begin to add weight to you could be a weight vest or something like that.

[03:17] There’s also studies that have add weights to your legs, which shows to be even more detrimental than weight around your midsection. Which makes sense because those are the things that are moving. Or if they don’t add weight to you, then they’ll take weight off which we can do now with these nice zero gravity treadmills that adjust how much we weigh. It’s great for injury training.

[03:39] Now, if you think about this, you have to think, okay, if I gained this many pounds, then I’m going to be slower by two seconds per pound that I gain. That’s bad, right? So, I always want to be skinnier. Wrong. Absolutely wrong. Because in these studies, you’re putting completely non-functional weight on or off of a participant and saying this is what changes, this is the effect or the speed change that happens when we change weight.

[04:14] Now, I’m going to show you a few pictures here of me over my running career and into my triathlon career. It may be a little hard to see the differences but I will explain them as we go on. So, in high school, I raced. I started high school about 130 pounds. Here’s me. I’m very tiny in the middle of that group.

And then as I kind of got a little bit bigger, grew a little bit in high school, I kind of got to the point where my racing weight was around 143 pounds. Now, my fastest 5K time in high school was 17:47, something like that. Junior year, sectional qualifying meet, still upset about that because I missed out on the state by 12 seconds. That’s why it sticks in my mind.

[05:04] In any case, if we went by this rationale that I need to lose weight to get faster, I would have to go from 143 down to what, say 120. And then I’ve gained 40 seconds per mile, I’m going to be so much faster if I do that. But that’s not what happened. As I went to college, began training more, I gained more weight. From freshman year – beginning of freshman year to the beginning of sophomore year, I went from 143 pounds to 152 pounds. I gained 10 pounds in that year.

Now, you may be thinking, freshman 15 sneaking up. But no, I was actually probably leaner than I was before. But I gained a lot of muscle through strength training, through the speed work we were doing, and partly just from aging from growing more. And consequently, my times went down, I got a little bit faster.

[06:02] Throughout college, I gained a little bit more weight. Went from 152 to my kind of optimal racing weight in college, again, junior year was around 156 pounds. At this time, remember, in these four years from high school to college, junior, junior year, I have gained 13 pounds by now, two minutes faster, in my 5K time because this is functional weight.

This is the fallacy of those studies. They’re adding non-functional weight to your body and saying, hey, this is what happens when you gain weight.

[06:47] Now, there is a limit. Of course, there is a limit. But it isn’t necessarily there because I went on in post-college started doing triathlon and got a little bit better upper body, although again in this picture, a little hard to see that, maybe. And in that time I went from racing 156 pounds to my fastest 5K ever, at a 163 pounds, I broke my own bike [??? 07:13] record by two seconds, just barely eked it out and really shouldn’t have been able to do it because I was running half the miles as I was in college. But there is something to be said for a large gain in overall fitness.

[07:25] So, we look at this on the spectrum, in high school, running high 17s to after college, couple years after college 163 pounds. I’ve gained nearly 20 pounds, yet I’m still two minutes faster. So, it is not an absolute sense that you have to lose weight to be faster. The exception to this situation is if your body fat percentage is really high, and you need to bring it down to be leaner.

This is where the studies do have some efficacy because that body fat is largely going to be non-functional weight. That’s why when we ask, does gaining weight affect my speed? Well, yes, but not always negatively. It depends. That’s that coach’s thing. Remember, it depends, depends on your situation.

[08:20] So, if you have a high body fat percentage, then bringing that down will likely make you faster. It’ll also reduce the amount of pressure and pounding on your joints. That’s a positive thing. And you can probably convert some of that into muscle, gaining more functional fitness in the process. Which means altogether if you’re gaining muscle losing fat, then you can be faster.

There are downsides though. And this is why I want to be careful about this conversation because just saying we need to lose weight to be faster, as I’ve shown, with myself. I know I’m a case study of one but I’m not alone. And there’s growing evidence that this is the truth. There are plenty of people that fall prey to this that do not need to lose weight. And when they try to lose weight they end up in a world of hurt.

[09:18] Most famously, Ryan Hall, who is a very, very well known top Level marathoner. He’s left the sport. But he got to the point where he could barely run. He was so injured. He was so thin. I think he was about my size if I remember right, 5’10, and he was only 130 some odd pounds, 135. Although it’s great in one sense that he’s trying to be fast.

He had gotten to the point where his body was so overworked, his hormones were so out of whack. And he couldn’t keep it up anymore. He was just obliterating himself. He’s now gained 30 pounds, predominantly of muscle, left running competitively, gain a larger perspective on a healthy life. So, there is a limit to up and down kind of weight and how you should approach it.

[10:11] One of my favorite books by author Matt Fitzgerald, racing white, I highly recommend picking up this because Matt is in our community, Matt is in the endurance community. And he talks about the things that we need to consider when we’re trying to optimize our body weight, not just lose weight, to become faster.

I should also mention, Matt was kind enough to come on my show, the Smart Athlete Podcast. So, if you have not seen that, you don’t know anything about that, subscribe to the channel, then go check out my conversation with Matt, where we talked about – I briefly mentioned racing weight, if I remember correctly, and we talked about his new book, really great guy.

[10:49] But if you’re concerned about your weight, you want to be faster, you want to be more optimized, then please check out Racing Weight. I don’t get paid anything for this. This is simply a book I have had on my shelf, which is why I was happy to talk to Matt. It’s been influential to me, and something I come back to time after time after time.

[11:10] So, again, seeing those studies to say, hey, if you lose this way, you’re going to be two seconds per pound, faster per mile. Ignore that. Look at the deeper situation that you are in. Let Matt guide you with Racing Weight. And hopefully, together taking a deeper look at your situation, your diet, your training, schedule, all those kinds of things; you can find an optimized way for you to become as fast as you possibly can be. I’ll see you next time on the next episode of Runner’s High.

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