Athletes: Fit but Unhealthy?
Open accessAbstract
While the words "fit" and "healthy" are often used synonymously in everyday language, the terms have entirely separate meanings. Fitness describes the ability to perform a given exercise task, and health explains a person's state of well-being, where physiological systems work in harmony. Although we typically view athletes as fit and healthy, they often are not. The global term we place on unhealthy athletes is the overtraining syndrome. In this current opinion, we propose that two primary drivers may contribute to the development of the overtraining syndrome, namely high training intensity and the modern-day highly processed, high glycemic diet. Both factors elicit a sympathetic response through the hypothalamic-pituitary-adrenal axis, in turn driving systemic reactive oxygen species production, inflammation, and a metabolic substrate imbalance towards carbohydrate and away from fat oxidation, manifesting in an array of symptoms often labeled as the overtraining syndrome. Ultimately, these symptoms reveal an unhealthy athlete. We argue that practitioners, scientists, and athletes may work towards health and alleviate overtraining syndrome by lowering training intensity and removing processed and/or high glycemic foods from the diet, which together enhance fat oxidation rates. Athletes should be fit and healthy.
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BMI is a poor measure of obesity status in athletic cohorts such as rugby or American football players, who often have large lean mass and relatively healthy percent body fat levels (typically 12-20%).
“For example, Rugby or American football players commonly have large amounts of lean mass, and many will have relatively healthy percent body fat levels, typically 12–20%, so BMI is considered to be a poor measure of obesity status in these athletic cohorts.”
From The athletic gut microbiota (2020) · cites this paper as [67]
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- Authors
- Maffetone, P. B., & Laursen, P. B.
- Affiliations
- Oracle (United States) (US)
- Auckland University of Technology (NZ)
- Corresponding author
- Laursen, Paul B.
- Venue
- Sports Medicine - Open
- Published
- 2016-05-26
- Volume
- 2
- Issue
- 1
- Pages
- 24-24
- ISSN
- 2198-9761 (ISSN-L)
- 2199-1170
- PMC
- PMC4882373
- OpenAlex
- W2403008365
- Cited by
- 46
- References
- 26
- Citations by year
- 2025: 3 · 2024: 14 · 2023: 6 · 2022: 2 · 2021: 4 · 2020: 6 · 2019: 5 · 2018: 2 · 2017: 4
- FWCI
- 4.47
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Locations
- Sports Medicine - Open (publishedVersion, cc-by)
- Europe PMC (PubMed Central) (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- Topics
- Health Sciences › Medicine › Orthopedics and Sports Medicine › Sports Performance and Training
- Health Sciences › Medicine › Rehabilitation › Exercise and Physiological Responses
- Health Sciences › Medicine › Complementary and alternative medicine › Cardiovascular and exercise physiology
- Keywords
- overtraining syndrome, athlete health, exercise intensity, processed foods, hypothalamic-pituitary-adrenal axis, sympathetic nervous system, reactive oxygen species, inflammation, fat oxidation, carbohydrate oxidation
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