Weight - extra weight - affects runners more than cyclists and swimmers but all endurance athletes can benefit from getting leaner. The pull of gravity impacts the mechanics of running more than it does the rather static form of cycling or the well supported position of swimming. Regardless the lower your percentage of body fat the more efficiently your body moves. The smaller the person, the more efficiently oxygen is delivered where it needs to go - blood simply has less distance to travel.
Dieting is a problem - the end goal of a diet is losing weight - any weight - even muscle. Endurance athletes need to focus on only losing fat. If calories are cut too much you will stop the supply of energy your muscles need to maximize performance. You want to keep your training up and be conscious of the quality of the calories you are consuming. Matt Fitzgerald, author of the book Race Weight, suggests thinking of this focused type of eating as performance weight management. The research bears out that the longer the races, the better the performance with a lower body mass index (BMI). A 2014 study found that the optimal BMI for male 800m runners was between 20 and 21, while it dropped between 19 and 20 for male 10,000m and marathon runners.
What is your race weight?
Unfortunately you will not know your ideal weight until you reach it - as your races improve monitor your body composition and weight and track it along with training and performance results. The ideal percentage of body fat is different for each athlete and varies based on age, genes, gender and weight history.
Optimal Body Fat Ranges, By Age
Men 20-29 | 3-10% 30-39 | 5-12% 40-49 | 6-15% 50+ | 8-17% Women 20-29 | 10-16% 30-39 | 11-17% 40-49 | 13-20% 50+ | 14-22%
How to get there without sacrificing performance
Improve your fuel
Endurance athletes have a balancing act - reducing the calories for fat loss but maintaining them enough for optimal training. Focusing on quality calories with nutrient dense foods like lean meats and fish, vegetables and nuts, as well as fruit and whole grains should meet your needs. If the focus is on clean eating you shouldn’t really need to track calories at all unless you are looking to meet a specific goal for a specific race.
Keep your carbs
Dropping carbohydrates can reduce the numbers on the scale but it also will reduce your performance. Carbs are essential to endurance athletes for training. Research shows that a reduction in carbohydrates leads to a reduction in training capacity. It goes against the fad diets of the 90s but maintaining quality carbs means maintaining training which means a leaner future you.
Hold yourself accountable
Get on that scale. Research on non-athletes has shown those that monitor their weight at least weekly are more likely to maintain weight loss. If they don’t, the weight comes back slowly gram by gram. There is no reason to doubt the same wouldn’t hold true for athletes. Monitoring will lead to management. Endurance athletes should check in at least weekly - ideally monitoring body composition with a body fat percentage scale. You can also pull out a tough workout to monitor your progress. Try it after two weeks, return to it after four and eight weeks - compare your results to monitor your improved performance.
Feed for fuel not fun
Don’t ignore your appetite. If you are hungry your body needs fuel. It is an old wives tale that to lose weight you need to be hungry. Athletes can trust the signals from their body if they are eating consciously with quality foods - that also means you need to stop when your body tells you it’s full. Don’t clean your plate! As you become more familiar with your nutritional needs don’t prepare extra food at meal times - this will reduce the instinct to finish what has been made. And never eat mindlessly or from boredom.