Why weight is not important to performance

In this blog, Coach Alan writes about why body composition is far more important to athletic performance than weight.

The ‘W’ word

Weight, there you go. I’ve said it; it usually is a word I actively avoid using in any situation with any athlete. Why? Because it is a metric that is inaccurate at best and dangerous at its worst.

Weight requires some other metric to make it relative and therefore accurate. Two people that both ‘weigh’ 80kg are very different if one is 170cm tall and the other 200cm tall, for example. Two people that ‘weigh’ 80kg and have a body fat percentage of 5.3% and 23.3% are also very different. Two people that ‘weigh’ 80kg but have a muscle mass percentage of 65 or 88% are also very different. Even within one individual, them weighing 76kg or 80kg could simply be due to a variation in their hydration status.

Further to these individual points, we also have to triangulate all of them to work out the athlete’s body composition. Even more importantly, we must work out the optimal body composition for that individual for the event they are trying to prepare for. Everyone will have some subtle and some not so subtle variations, and the oversimplification of all of this to the ‘W’ word is poor practice.

In terms of body composition, athletes require sufficient muscle mass to exert the forces required of their sport. All individuals have a genetically hard-wired somatotype: ectomorph, metamorph, or mesomorph. This is a baseline that is to some degree fixed in stone. Because it is set in stone, coaches and athletes should work with our natural baseline for our best performance to be achieved. 

If you have a poor ability to sprint, no matter how hard you try, you will not develop a world-class sprinting ability; you may improve against yourself and become ‘good’ but not world-class. The same can be said for somatotypes, and it is essential to remember this when considering body composition. As well as looking at weaknesses to improve, athletes must look to build on strengths; if they are naturally strong, get stronger. Make the most of that absolute strength you have as an athlete rather than focus on your relative strength.

For example, mesomorphs will naturally accumulate muscle mass and will be able to achieve high absolute force production across disciplines. Although their relative values, such as power:weight, may not be world-class, they will likely still do well by working with their muscle mass to push their absolute numbers as high as possible by doing more work. 

Ectomorphs will naturally be leaner and struggle to hit high absolute numbers but may be incredibly efficient.

However, these types of labels that we may give ourselves are still grossly simplified compared with the vast spectrum that exists in reality. Extreme endomorph to extreme ectomorph has many points in between, and some of these are state-based rather than trait-based. 

This is especially important for an essential base tier of our nutrition hierarchy are we consuming sufficient calories or not over-consuming calories. Most of us know what occurs when we consume excess calories, but what about when we don’t consume enough?

Heavier can be faster.

If inaccuracy and irrelevance of a number are bad, how about the argument that well lighter is faster as it’s more efficient. Well again, no. Not if you take the number in isolation.

Muscles are advantageous! It requires energy to develop muscle mass and adapt, and this is an anabolic process. Anabolism is vital to developing muscle tissue, bone density and also for maintaining our immunity. Another example of anabolism is gluconeogenesis, the production of glucose in the liver and kidneys. Glucose = energy (that sounds useful, right?) Well, actually, what if we don’t have enough energy?

Within cycling, the ‘old knowledge’ centres around W:Kg, but that thinking is only really relevant in the same way that the bike’s weight is only important in races where the terrain is almost entirely uphill. The only triathlon I know of where this is practically true is the Alpe D’Huez Short Course triathlon. Current thinking is much more towards W:CdA. Aerodynamics are that important. Part of the reason why riders with high absolute power are so significantly better than pure climbers is that there isn’t a linear relationship between drag and muscle mass. If our muscles developed sideways and sideways only, there would be a linear increase in frontal area, but that simply isn’t true. 

Strength training for swimming is essential again as drag through the water does not respond linearly with the ability to apply force and overcome drag. 

This brings us to running. The single most crucial aspect of running is not getting injured. Time and again, studies have shown that strength training has a positive effect on the incidence of injury in running; the prevalence of bony injuries in lean athletes is high. Elite high-performance athletes are taking risks with their training load rather than fuelling, possibly both. Still, some are now trying to offset this load in running by using Alter-G treadmills or suspension belts for running, for example. Whether or not this is relevant to amateur athletes who have other aspects of improving is questionable. 

All of these performance metrics are reduced with excess fat mass, especially running higher impact forces increase the stability required or reduce the performance output. So this brings leanness or body fat percentage into the conversation. Body fat is essential for our survival, health and performance. It would be easy to talk about ranges that work well for men and women, but the truth is those are generalised numbers in themselves. As age-group triathletes, there is a significant difference across age groups as well as gender. Inbetween yourself and the same gender athlete in the same age group in the same race, there will be a different range that works for you both in terms of health, performance, and too little, resulting in poor performance and potentially poor health.

Many of these variables I have written about sit on a bell curve, a bell curve that has a ‘Goldilocks’ vibe about it, too little, just right and too much. The truth is the section in the middle is the broadest one and chasing too much on the too little side comes with a rapidly increasing risk.

Risk vs Reward

What works well for one person may not work for the next. We are all different, and it isn’t just our physiology that I am talking about here. It is also our psychology and our daily environment. We all have a ‘risk’ factor associated with our everyday training environment. Professional athletes in high profile organisations have lived and worked within sanitised bubbles for years; sound familiar? In a twist we all never saw coming, bar Bill Gates (and others), so have the rest of us for the past 18months. It makes you think about how does each athlete’s biosphere vary? Do you work at home, work in a medical role, come into contact with the general public, and even have children of a school-age? All of these factors result in an increased likelihood of you being exposed to any illness. As such, your immunity and risk profile is significantly different to a mid-20s pro athlete who is single and lives in a ‘clean’ training bubble. 

Suppose you are pushing the boundaries of breaking 8.5hr for a Long Distance race, breaking 4hr for a Middle Distance, breaking 2hr for Standard or 1hr for Sprint. Then leanness might be something that you can look at. Still, importantly, you should be ensuring that you work with your body and take on board sufficient fuel; even with these lofty goals, health always comes first. Still, awareness of risk is also far better than ignorance of risk.

Health can be risked, and the absolute output can be sacrificed; personal strengths can be sacrificed while aiming for what everybody seems to think they need, which is to ‘look the part’. Triathlon is wonderful, with many body types performing well. It is crucial that all use awareness, perspective and the correct language. 


About The Author

Coach Alan Ward

Alan Ward

Alan has worked with Tri Training Harder since 2014. During this time working with a wide spectrum of athletes from beginner, to youth and junior elite athletes through to 70.3 and Ironman AG winners and Ironman Kona Qualifiers.

An active Triathlon coach since 2007 Alan has been fortunate enough to work with athletes, peers and support staff who have continutally challenged him to evolve and develop. Building on a solid foundation in swimming teaching, Alan has specifically developed swimming coaching experience having worked in High Performance Swimming environments. Alan's other passion is all things fast on a bicycle!

Since 2015 Alan has worked in conjunction with the other Tri Training Harder Coaches to significantly develop collective coaching practice both on camp and online.


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