Weight and its effects on female athlete performance

by May 2, 2021Uncategorized0 comments

Weight and its Affects on the Female Triathlete’s Performance

When we use the term ‘weight and performance’ in the same sentence, it traditionally conjures up negative thoughts like fat, heavy and slow to name just a few. In triathlon there is a strong movement towards the belief that lighter means faster.

So is weight really the negative it’s being made out to be or is weight being viewed too much as a black and white issue when the truth to its role in triathlon performance can only be found in the grey areas.

What are the physiological and psychological issues that accompany weight?  As a coach is there a better way to approach body composition for the purpose of improving performance rather than the current “less is more” approach that is so quickly being adopted?  Coaches seem to be without thought to the consequences of the individuals they are dealing with and the effect on their health and wellbeing in the long term.

As coaches it is our primary role to provide a safe training environment in which our athletes can develop to their full potential rather than the short term fix that weight loss can represent.

Before you read on ask yourself is your goal as a coach to create or have “short term success this season” or is the goal “a successful career”, which is more important? If the answer is the latter then this blog may very well change your approach and view of weight and its relation to performance.

The issue of weight is in front of us every day through the news media and we have become ultra sensitive to the perception of weight and how people view us relative to it. It has the ability to create numerous negative psychological issues when handled incorrectly by people in positions of power.  Eating disorders such as bulimia and anorexia are often common in our sport.

This issue however for athletes needs to be viewed differently.  While many coaches still look at weight in the same way the media portrays it, I believe it is important for coaches not to look at athletes in this way but rather in relation to the targeted end product, speed, power and race day results.

For athletes it is important to view weight not in terms of ‘lighter is better’ but rather in terms of power to weight ratios. The body’s composition effects buoyancy in the swim, functional and peak power on the bike as well as heat dissipation and mechanical efficiency on the run.

So if we look at an athlete from a power to weight point of view and assume that a higher power to weight ratio is going to give better results on race day then it is important to look at the individual components of this.  You can improve this ratio by decreasing weight but you can also improve this ratio by increasing the power side of the equation. Keeping this in mind it is important to then view these two sides of the equation in terms of the associated negative and positives to the athlete. While increasing power and improving fatigue rates have very few negative issues associated with it, decreasing an athlete’s weight is a potential minefield.

We are all very aware as coaches of how simple weight loss can turn into disordered eating and then into an eating disorder particularly with our female athletes. That is why how we approach weight loss is critically important.

First, from a psychological point of view you have to be hypersensitive to the approach of weight loss. You simply cannot approach the subject from a personal self image point of view i.e. you shouldn’t say “I think you need to lose weight if you are going to be a better athlete”. This coupled with the media and social stigma attached to weight will lead to lowering of an athlete’s self belief and the way they view themselves. If this happens then the goal of improving power to weight profiles and fatigue rates becomes secondary to goal of dropping weight.

A better and more productive way of approaching this issue is from a performance stand point. Ask the athlete what they feel is an ideal race weight for them and over what period of time they believe they should be targeting this weight and body composition. This creates in the mind of the athlete a stopping point for the weight loss and also allows the issue to be viewed in relation to performance rather than self image. As a coach, especially if you are working remotely, it is important to monitor an athlete’s weight for warning signs of overtraining and to ensure that the nutritional demands relative to training loads are met. By having an athlete set out their goals and comfort zones, you minimize outside pressure allowing you to discuss their weight and ask them to record any gains or losses.

Regardless of how you approach this topic with athletes there are still risk factors particularly with female athletes. We are all familiar with the Female Athletes Triad outlined in the diagram below. Disordered eating, leads to loss of the menstrual cycle (amenorrhea) and then to bone calcium loss which will eventually lead to stress fractures and a high injury profile in training.


All too often we see this scenario play out with our elite female athletes. Amenorrhea is the easiest to spot within this model especially if we have good open lines of communications with our athletes. But we should not be too quick to jump to the assumption that just because an athlete has Amenorrhea the athlete is experiencing the Female Athlete Triad.  In most cases I have been involved with the athlete does not have disorded eating but due to their body size and the energy requirements of training as an elite triathlete they simply cannot get enough food to fuel the requirements of the sport. This situation is referred to as “Low Energy Availability” or “LEA”. From a coaching point of view you may do everything right but still find yourself in a situation where LEA is a factor and the female athlete still ends up with Amenorrhea. In this situation the solution may be to look for ways in which the season can be periodized from a physiological and a nutritional point of view.

In most cases, the year of a Triathlete can be broken down into two major parts, in season and off season. It’s important to break down the races into long course and short course races as the physiological requirements of each are different and thus body composition is also slightly different for each. For long course races athletes tend to be slightly heavier than for Short Course races. With long course athletes it appears that more muscle mass leads to a decrease in muscle fatigue caused by sustained levels of muscle activation over long periods of time. Short course athletes tend to have higher outputs for shorter periods of time. However due to increased speeds being slightly lighter there is a decrease in impact per stride on the run thus allowing an athlete to go faster with a lower fatigue rates.

So how does this affect both the body weight and composition of an elite female athlete to ensure they stay as healthy as possible both during and after the competitive season? During the off season it’s a wise idea to ensure that athletes are a little heavier than during the racing season. Additional weight will not only assist athletes to stay healthier during the colder months, it will make them less likely to get traditional winter illnesses. It also allows female athletes to escape the trap of year long amenorrhea and allows them to get back to being within a healthier weight range which will in turn help their hormonal balance as well as skeletal health.

The Triathlon season runs from March – November each year. If we have our female athletes begin the season slightly heavier to avoid LEA and maintain a good hormonal balance until at least May then we should set ourselves up well for the season without compromising the athlete’s performances late in the season while also making our athletes less prone to skeletal injuries.

Once the season begins it is important to try to prevent amenorrhea and iron anemia in our athletes by trying to maintain the quality of their food intake and careful consideration when planning the training load an athlete is sustain. However should athletes begin to suffer from either of these then there are steps we can take to minimize the impact on bone density and associated stress fractures. An increase in the amount of supplemented calcium will assist in maintaining bone calcium especially when taken in conjunction with Vitamin D. However coaches should NOT suggest athletes cut back on fats and increase carbohydrate in their diets. The caloric values in fats are much higher and therefore provide higher energy levels reducing the risk of LEA. In fact a study done by the American college of sports medicine, while looking at the Female Athlete Triad had this to say:

“energy deficits are more extreme when consuming a high carbohydrate diets such as those recommended to endurance athletes”

Studies have shown that amenorrhea increases from 3% to 60%, within distance runners when their running volume is increased. Coaches should be wary of the affect volume may have on the female athlete triad especially amongst long course athletes.

 Iron anemia also is a major concern as well. Iron anemia can be caused by dietary restrictions of high protein foods, as well as exercise based causes of to high of volume and environment. Every time an athlete’s foot makes contact with the ground, it compresses capillaries damaging red blood cells. The body naturally must produce more red bloods cells and depletes the body’s iron stores while doing so. A few minor fixes can help prevent iron anemia.  Either increase the foods in high iron or protein and for vegetarian athletes add in quality iron supplements. Cutting run volume and running on softer surfaces will decrease the impact the foot makes with the ground and the damage it incurs.

During the season we can naturally expect that some of our lighter females athletes will suffer from LEA due to the race load and requirements of training and travel.  So rather than ignoring it we simply have to look at ways to minimize the effects it has on the body.  If you determine that it is more serious such as the female athlete triad or bulimia then get them to seek out professional help (not always easy). Once the competitive season finishes look towards increasing body weight a little from their traditional race levels and focus on quickly re-establishing a healthy weight range and balance of normal body systems.

It would be naive to believe we can prevent amenorrhea in all our female athletes at high level for the entire racing year. Some athletes due to size and energy outputs are always going to have hormonal and weight related issues. However if we are smart and focus on remembering when an athlete needs to be lighter and when it is more important to be healthier then it is possible to peridoize a training and racing season so that athletes can have successful racing seasons without compromising their long term physiological, psychological or medical well being in the pursuit of performance.


            American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed.  Washington, DC: American Psychiatric Association, 1994.

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