New guidelines for body composition testing and why we are here for them!
The ‘ideal’ body fat percentage for best performance in a given sport has long been a topic of discussion. But is body fat actually a reliable indicator of performance? Body composition testing is often performed on athletes, as it offers more specific information than scale weight alone. Results are expressed as percentage of body fat and pounds of ‘fat free mass’, which, as the name suggests, consists of the remaining parts of our bodies that aren’t fat - bone, muscles, water, and other cells and minerals.
In treating athletes with eating disorders over the past several years, we’ve encountered many who were encouraged to strive for a certain body type or percent body fat, usually drawing inspiration from professional athletes in their sport. Too often this serves as a catalyst for the onset of the eating disorder. This is especially problematic for youth and young adult athletes, whose bodies must change, shift and develop, year after year, in order to thrive.
The IOC recently published a comprehensive review of research on body fat and performance, which included new recommendations for best practices for body composition testing. Here are some key findings:
While increases in muscle mass were consistently related to better performance, decreases in body fat were not.
In fact, rapid weight loss was associated with adverse health and performance outcomes.
So not only is the emphasis on body fat reduction distressing for the athlete, but it’s also an unreliable performance metric for the athlete and their support team.
Put simply, this research puts to rest the myth that there’s an ‘ideal’ percent body fat that an athlete should be pursuing in order to be more successful.
IOC recommends the following to reduce potential harms associated with body composition testing:
A multidisciplinary team should prescreen athletes for risk of negative outcomes (such as eating disorders) prior to body composition testing. If it is deemed beneficial, there should be a clear rationale for testing.
Frequency matters…..testing should be done as infrequently as possible.
Focus discussion on lean body (muscle) mass changes, not body fat.
Treat results as one would treat any protected health information, and obtain consent from the athlete before sharing results.
Don’t test individuals under 18 years of age, unless it’s absolutely medically necessary.
The IOC’s findings and guidelines echoed sentiments that folks in the eating disorder treatment space have been shouting from the rooftops for decades: While body composition testing has its merits, recommending weight or fat loss can have a host of harmful downstream consequences. It requires a good rationale, and thoughtful consideration of pros and cons.
Interested in a deeper dive? Check out this BJSM podcast episode “To Measure or Not to Measure”
