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Find Your Ideal Racing Weight

For those looking to lose a few pounds, the ideal weight is something lower—or much lower—than the number currently on the scale. But what about endurance athletes who already are in good physical condition? What’s their ideal “racing” weight? Endurance nutrition guru Matt Fitzgerald explores that topic in his new book Racing Weight: How to Get Lean for Peak Performance (Velo Press). He recently spoke with CorePerformance.com.

Core Performance: So how do you determine your ideal racing weight?

Matt Fitzgerald: It would be nice if there were a simple formula where you could plug in age, gender and a couple other variables and have that number spit out of a machine, but that doesn’t exist yet and may never. Your optimal performance weight has to be functionally defined. What it means is simply the weight that allows you to perform at your best. One way to determine that is to get in the best shape of your life and when you have the performance of your life, get on the scale. That may not be useful or practical, so I also provide a way to find a realistic number based on the collective data on body fat levels for different ages. Although most of us don’t have the genetics and (natural) speed, we can dial in nutrition to get into the top end of that range. That becomes your target based on age/gender.

CP: It sounds like it’s more about optimal body composition than body weight.

MF: That’s exactly right. There are certain characteristics you can’t control in terms of height, body structure, how much muscle mass you carry. What’s true of any athlete in peak condition is that they have low body fat percentage and that becomes the target to focus on and then you can go back and calculate what your optimal weight would be at that body fat level. You can use that indirectly to find what the weight associated with that body fat would be.

CP: In your book you mention that body composition scales are almost as effective as DEXA scans when it comes to such measurements.

MF: Not quite as accurate but what I point out in the book is that it’s reasonably accurate and what’s more important is consistency. You wouldn’t want to use it to compare your body composition to others, but what it does effectively is track trends within your own body and that’s all you care about. Is my body fat percentage going up or down?

CP Is there any value to counting calories for the endurance athlete?

MF: There are a lot of ideas that make sense in principle but in practice it makes your life a nightmare. Counting calories just isn’t fun. It’s not something I like to do myself but there’s a place for it. It’s like auditing in finance. You can check in periodically, but you don’t need to know it every day. Counting calories is useful to go through on occasion to see where you are. Dial things in and once they’re dialed in you don’t have to do it every day. It all comes back to food. Figure out what gives you the calories that give you what you need and stay consistent. When you change your training or diet, do another audit to make sure the balance is right.

CP: Some of these things seem challenging to apply to, say, cycling, where you’re already trying to balance your power-to-weight ratio.

MF: It’s important no matter what your sport is to never take your eye off performance. That’s the end game. We get ourselves into trouble when we focus on the means not the end, thinking that the thinner I get, the better I perform. No, not necessarily. You never want to take your eye off those performance metrics. There is such a thing as becoming too lean. With cycling, you’re paying attention to your weight and body fat, trying to get lean without sacrificing performance. I encourage athletes in every sport to do performance tests every four weeks as a way to check in. Are the changes in my body helping performance? If you’re getting leaner and slower, you know you’ve gone too far. These performance checks are a great way to measure. For cycling, that performance test is simple—a time trial.

CP: Runners tend to obsess more about calorie restriction, but in the book you suggest running more might be the answer.

MF:  I have a foot in triathlon, cycling, and running. They’re all different cultures and one of the aspects of the culture of running is that they would never train at the level of cyclists and triathletes. They would never think of running twice a day, for instance. The point is most runners put a ceiling on their training that’s culturally based, what the norm is of other runners, not what their bodies could benefit from. Triathletes often train twice a day. I encourage runners to shift their mindset and realize they could train more than they do. Of course, use caution and start slowly and listen to your body. But doing some cross training or running more could benefit them by helping them lean out a bit.

CP: What about swimming, where a little higher body fat can be viewed as a good thing?

MF: It’s not that they have naturally higher body fat levels. The way they train, they end up with a little more fat on their bodies. Every sport evolves and one of the recent trends is on more dryland training, strength training in particular. Having a little strength for muscles through the water is helpful. Dara Torres and Michael Phelps have done more strength training and it clearly helps. Where body composition comes in to play is that even though the aim is to gain strength, you can’t gain strength without muscle. When you gain muscle, the bodyfat percentage goes down and it may result in fat loss. Muscle is a furnace for fat. So if you add a couple pounds of muscle you increase the metabolic weight and that will burn fat.

About The Author

Pete Williams – Pete Williams is a contributing writer for CorePerformance.com and the co-author of the Core Performance book series.

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Tags: Swimming, Triathlon, Training, Sports Performance, Outdoor Recreation, Cycling, Running