Inadequate energy intake affects female athletes

Diet and training go hand in hand if you want to achieve the best results. Most athletes know this, and many of them monitor their energy intake and training closely. However, a new study from the Department of Public Health at Aarhus University shows that the bodies of female athletes are negatively affected when the athletes consume too little energy through their diet compared to their training volume, explains PhD student Mikkel Oxfeldt. He and Associate Professor Mette Hansen are behind the research.

“We know that both top female athletes and active women sometimes, consciously or unconsciously, do not have an energy intake that matches their energy expenditure during training. The research shows that insufficient energy intake can have a negative effect on the ability of the muscles to respond to After just ten days of low energy intake, we started to see changes in the hormonal system, such as a decrease in metabolic hormone , followed by a decrease in metabolism.’

The research shows that it is important for women to be careful not to reduce their energy intake too much. In fact, they should actually increase their energy intake as they increase their training volume, says Mikkel Oxfeldt:

“If you don’t get enough energy from your diet, your body starts to slow down processes that require a lot of energy, much like a cell phone going into battery-saving mode. We know from previous studies that this can lead to menstruation. However, our results show that other processes in the body, such as the build-up of new muscle proteins, are also affected.”

We must confront the one-sided focus on weight

Thirty fit women aged between 18 and 30 took part in the study, which is part of the Novo Nordic-funded Team Denmark network called ‘competition preparation and training optimization’. All women started the study immediately after the start of their period and followed a highly controlled exercise and diet regimen for three weeks.

“Under the supervision of the researchers, the participants performed individual training programs aimed at increasing muscle mass, strength and overall fitness. We also provided the women’s meals. By monitoring their training regimen and their diet, we were able to see how much energy they expended and what they ate during the study,” says Mikkel Oxfeldt and continues:

“This is the first time such a well-controlled study has been conducted in this area, with both the diet and exercise of a group of fit women regulated to this extent. During the study, all participants drank double-labeled water. “, which is enriched with trace material. When we combine this tracer technique with the retrieval and subsequent analysis of muscle tissue samples, we can gain detailed insight into the response of the muscles to the experimental protocol,” explains Mikkel Oxfeldt.

Mikkel and the research group believe that it is necessary to confront the idea that weight loss leads to medals, when in fact weight loss can negatively impact a number of body systems, including the muscles.

“In recent years we have heard about public weigh-ins within some elite sports. They are part of promoting a culture where some women are constantly trying to lose weight. However, our results show that this focus on weight loss can have negative consequences on the short and possibly long term for women, both in relation to their health and training results. The research will hopefully give athletes and coaches a more nuanced picture of possible side effects.”

In collaboration with colleagues from the University of Copenhagen and the University of Southern Denmark, the researchers behind the study are now investigating how physical performance, the immune system and metabolism are affected by insufficient energy intake. They hope to one day be able to determine whether there is a difference between the way women’s and men’s bodies respond to insufficient energy intake.