Racing Weight: Should Runners Care?

Molly Hurford
by Molly Hurford
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Racing Weight: Should Runners Care?

We often hear the phrase ‘race weight’ tossed around by runners at start lines of races. Hitting a certain number on the scale — maybe the weight you were when you won that 5K when you were 23, or your pre-baby weight or even just that oh-so-common “I want to lose five pounds before race day” weight.

Hitting a race weight might sound like it would be performance-enhancing, and it’s certainly tempting. There is some truth to the fact that being lighter may aid your performance, but striving for a certain number specifically for racing season, versus looking to optimize your body composition to a healthy status year-round, might not be the right tactic for you as a runner.

“Race weight is really on everyone’s mind at the beginning of the season,” says Lori Nedescu, a pro racer and registered dietitian. “For most sports, you’re likely to perform a bit better if you’re at a lighter weight, so it does matter, but if you do it in a way that’s not well thought out, you won’t get you those better results.”

Here’s what the experts want you to know about race weight, so you can start deciding if it’s a wise decision to pay attention to the scale heading into this season.


The hardest part about deciding if you should target race weight is knowing what that racing weight should be. “I find a lot of athletes think about getting to race weight but not actually having a number in mind or a reason for the number that they think they should hit,” says Nedescu.

We pick an arbitrary weight based on what a friend weighs, or the lowest we’ve ever weighed, but that might not be the right weight for us. You can tell by tracking your races, how you feel and your measurements over time. You’ll see patterns of when you’re feeling the speediest and when you’ve crossed over into too lean territory — once you find that optimal spot, you’ll know where you want to go. But Nedescu begs racers to stop using the generic “lose 5/10/20 pounds” as their ‘race weight’ goals.


When it comes to measuring up, your race weight might not be a weight at all. Maybe race weight doesn’t mean a specific number on the scale. It might mean the way your favorite running shorts fit or how you feel on a run. Remember race weight isn’t supposed to be about the number, it’s supposed to be about optimal performance. “Don’t think about it as trying to weigh a certain number on the scale, think of race weight as a complete picture: How are you performing, how do you feel, what’s your overall body fat percentage, what’s your energy, what’s your mood — those are all super important factors,” says Nedescu.


“I see people trying to hit race weight right before a race, and they think they can go into a race at a huge deficit so they go in entirely under-fueled,” says Dana Lis, PhD, a registered dietitian and Director of Performance Nutrition at UC Davis. “People get too aggressive, too fast, taking unsustainable approaches.” You should be thinking about hitting any weight-loss goals several weeks ahead of your race season — trying to cram weight loss into the weeks leading into your race won’t have you hitting the start line lean and mean, you’ll be more likely to toe the line feeling under-fueled and fatigued.


Bad news: When you hit a certain number on the scale, expect it to fluctuate throughout the day and throughout the week. (Pro tip: Try to weigh yourself at the same time and same way to minimize fluctuations.) Don’t plan to hit a certain poundage, like 140 pounds, for example. Instead, think in a range, like 140–143 pounds, so you allow for water weight and variations throughout the day. This also helps you avoid relying on dropping only water weight. “If you get super dehydrated, you might be down a few pounds, but you won’t be any faster,” Nedescu points out. “That’s not the way to obtain race weight goals. Think it through.” Don’t skimp on your nutrients or your hydration for the sake of a number: Fluctuations happen regardless.


Hitting race weight only works if you’re not looking to lose a lot of weight, which means staying reasonable in your off-season. “Only gain 2% above your ideal race weight,” says Lis. (For that 140-pound runner, than means only a 3–4 pound increase in the off-season.) “I think people tend to go overboard in the off-season and then need to figure out how to drop more weight,” she adds. “But aim to stay within that healthy range all year long — not always at your leanest, but not bouncing so far away from your optimal race weight that it’s hard to come back to.”


It’s easy to get wrapped up in losing weight, but athletes need to be wary of dropping too low. “In some cases, gaining weight might even be helpful,” Nedescu says. If you suffer from any symptoms of Relative Energy Deficiency Syndrome (RED-S) like a loss of your period for women, then that might be an indicator that you’re already below your optimal racing weight and you’re putting your body at risk. “Your risk of injury and illness goes up as you try to lose weight, and for most athletes, diving into the race weight game isn’t worth it,” she says.


If you’re not a professional athlete, thinking in terms of race weight might be a bad idea. “Shaving off those last couple pounds will be taxing on your body — you’re working right on your body’s limit. Race weight isn’t meant to be sustainable,” explains Nedescu. For professional runners, being at that race weight is part of the job. But unless you’re getting paid the big bucks to run, race weight may be one stress too many on top of family, career and other hobbies. “Quality of life and fitness level is enhanced by a healthy diet, not by worrying about losing weight. It might translate into weight loss if you have weight to lose, but it might not. If you feel good performing and are performing well, you probably don’t need to add the stress of losing weight,” she adds


Remember: Your best performance isn’t found on the scale, it’s found by fueling your body for the work that you’re doing. “If you’re doing a few recreational runs per week, it’s nice to get into shape for the season, but I wouldn’t think about being obsessed with a couple pound difference,” says Lis. “For the average runner, there are so many gains you’re going to get from improving your nutritionfitness and sleep, and they’ll all be much more measurable than the small change in weight. Having good nutritional habits is more important than anything like hitting a certain race weight.”

Nedescu agrees: “Think about ways you can eat to perform better, which might mean packing a healthier lunch or having a better pre-workout snack. Don’t focus on weight loss, focus on a high-quality diet.”

About the Author

Molly Hurford
Molly Hurford

Molly is an outdoor adventurer and professional nomad obsessed with all things running, nutrition, cycling and movement-related. When not outside, she’s writing and podcasting about being outside, training and health. You can follow along with her adventures on Instagram at @mollyjhurford.


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