“You Need to Lose Weight”: Why Body Conversations in Sport Need Care

“You need to lose some weight” is thankfully not something we tend to here so often any more (correct me if I'm wrong?). But in endurance sport especially, body composition can feel like the elephant in the room.

Coaches, caregivers, and athletes often walk a difficult line between wanting to support performance while also protecting health and wellbeing. In sports like running and cycling there is a long-standing belief that lighter means faster, and while body composition can sometimes influence performance, the relationship is far more complex than a simple equation. Beyond a certain point, insufficient nutrition and excessive leanness can actually impair performance, recovery, hormonal function, bone health, and mental wellbeing, and ultimately lead to REDs (and/or an eating disorder).

At the same time, it's also important to acknowledge that the opposite can happen too, particularly in younger athletes. In reaction to harmful diet culture or fear around restriction, some athletes may take the “eat more” messaging to an extreme, or struggle to find balance during puberty, with changing training loads and busy lifestyles. Others may naturally carry additional weight that could potentially impact performance. But the weight issue is rarely simple.

One of the most misunderstood aspects of REDs is that an athlete can appear “overweight” while still being significantly under-fueled, as chronic under-eating, stress and hormonal disruption can alter metabolism, recovery and hunger signals. Ironically, pushing harder for weight loss in these situations often worsens the underlying issue.

In every case, navigating this conversation safely requires care, patience and perspective. This matters hugely in youth sport, because when weight becomes the primary focus, young athletes can all too easily drift toward harmful habits.

The hidden harm of casual comments

Many harmful conversations around body composition don't happen with cruel intent. In fact, they are often framed as motivation, concern, or even praise.

Comments like:

• “You’d be faster if you leaned out a bit”

• “You’re looking really lean”

• “Have you thought about adjusting your diet?”

• “That’s a lot of food!”

• “Let's get you down to race weight”

may seem harmless, but athletes often internalise these messages deeply, especially if they're still young and impressionable (but at any age really).

A single comment can reinforce a fear of weight gain, guilt around eating, restrictive behaviours and body comparison. And for those already vulnerable to REDs, eating disorders, perfectionism, or anxiety, these messages can become extremely dangerous.

So should we never talk about body composition?

Not necessarily. Pretending body composition is completely irrelevant in sport can reduce trust and credibility, particularly in high-performance environments. But conversations should be approached carefully, professionally, and only when genuinely necessary. The safest and most effective approach is usually to emphasise fueling, recovery, training quality, strength and consistency. In many cases, once these foundations improve, body composition and performance improve naturally too.

And if body composition genuinely becomes relevant to performance goals, those conversations are best supported by qualified professionals such as sports dietitians and healthcare providers, not casual sideline comments. The goal is not to avoid difficult conversations, it's to have them responsibly.

Athletes are not machines - they are humans navigating pressure, comparison, identity, expectations, and changing bodies, often while trying to perform at a high level.

The athletes who perform the best (in the long-term at least) are those who fuel adequately, recover properly and train consistently.

Long-term performance is built on long-term health and that starts with the messages athletes hear every day.