How does energy availability affect bone health and the gut microbiome in endurance female athletes?
Did you know that low energy intake can not only decrease sports performance but also have long-term impacts on bone health and gut microbiome balance? This research focuses on this current issue. The goal is to understand how varying levels of energy availability affect bone health and the gut microbiome in female endurance athletes.
What is low energy availability (LEA) and why is it so crucial?
Low energy availability (LEA) occurs when the body does not receive enough energy to cover normal physiological functions, which in athletes may result from intense training combined with low energy intake. This condition can lead to Relative Energy Deficiency in Sport (RED-S), a syndrome associated with several health complications, such as reduced bone density or changes in the composition of the gut microbiome (Mountjoy, 2023).
LEA and RED-S can have more specific and risky consequences in women than in men. A decrease in estrogen and progesterone levels, a common result of LEA, directly weakens bone structure and increases the risk of osteoporosis and stress fractures, which is a significantly higher risk compared to male athletes (Ihalainen et al., 2024). Hormones like estrogen also influence the composition of the gut microbiome and contribute to maintaining bone health, and low energy intake can significantly disrupt these protective effects (Pugh et al., 2021).
The gut microbiome plays a critical role not only in digestion and nutrient absorption but also in the overall immune response and regulation of inflammation. Microorganisms in the gut also interact with hormonal processes and can influence stress and cognitive functions through the so-called "gut-brain axis" and bone health through the "gut-bone axis" (Pugh et al., 2021). Women generally exhibit specific differences in their microbiome compared to men, with greater gut microbiome diversity being linked to better stress management and supporting bone health.
How is the research conducted and what does it monitor?
Each participant will be observed for 8-10 months, during which time various energy intake levels will be assessed to determine their effect on bone metabolism and the composition of the gut microbiome. The results of this study could provide insights into the long-term impacts of low energy availability, helping to improve RED-S prevention and contribute to optimal health for endurance athletes.
Participants will undergo five sampling weeks spread across 8-10 months. Each sampling week involves blood tests at an external facility near the participant’s home, stool sample collection, and a three-day nutritional diary to provide detailed information on diet and energy intake. Additionally, bone density will be measured using a DEXA scan and body composition analysis using the InBody 770 machine at the Faculty of Sports Studies in Brno during the first and last sampling weeks.
What will participants gain from the research?
Participants will receive detailed information about their bodies, which could help improve their sports performance and overall health. The results from the DEXA scan will provide accurate data on bone mineral density, which is crucial for preventing osteoporosis and ensuring strong, injury-resistant bones. The bone metabolism analysis will reveal biomarker levels, showing how bones respond to training load and whether bone mass loss is occurring. The gut microbiome analysis will also give insight into the status and composition of the microbiome, helping to identify potential imbalances that may affect digestion, immunity, and overall recovery after training. In this way, participants will learn how their body responds to training and nutrition and use these findings to optimize performance and long-term health.
How to apply?
You can express your interest by filling out two short questionnaires on this link. After completing them, you will be contacted with further information.
References:
Mountjoy, M., Ackerman, K. E., Bailey, D. M., Burke, L. M., Constantini, N., Hackney, A. C., Heikura, I. A., Melin, A., Pensgaard, A. M., Stellingwerff, T., Sundgot-Borgen, J. K., Torstveit, M. K., Jacobsen, A. U., Verhagen, E., Budgett, R., Engebretsen, L., & Erdener, U. (2023). International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). British Journal of Sports Medicine, 57(17), 1073-1097. https://doi.org/10.1136/bjsports-2023-106994
Pugh, J. N., Lydon, K., O’Donovan, C. M., O’Sullivan, O., & Madigan, S. M. (2021). More than a gut feeling: What is the role of the gastrointestinal tract in female athlete health? European Journal of Sport Science. https://doi.org/10.1080/17461391.2021.1921853
Ihalainen, J. K., Mikkonen, R. S., Ackerman, K. E., … & et al. (2024). Beyond menstrual dysfunction: Does altered endocrine function caused by problematic low energy availability impair health and sports performance in female athletes? Sports Medicine, 54, 2267–2289. https://doi.org/10.1007/s40279-024-02065-6
