Unleashing the power of fasted training has captivated athletes and fitness enthusiasts alike, promising a path to enhanced fat burning, metabolic flexibility, and elevated performance. However, this ascetic approach is not without caveats, particularly for women.
A Fitness Trend With Some Scientific Backing
Intermittent fasting and time-restricted eating have profoundly influenced our eating habits, Ian Craig, a nutritional therapist and exercise physiologist, told The Epoch Times.Fasting is a popular strategy for various health benefits, including optimizing blood lipids, reducing oxidative stress and inflammation, facilitating cellular detoxification, promoting gut rest, managing weight, and stabilizing insulin levels. There has been a surge in fasted training—which is exercising while in a fasted state—among athletic communities, underscoring its relevance for sports performance, Mr. Craig said.
The Hidden Risks of Fasted Training
While restricting food intake before and during exercise can induce a state of cellular stress, potentially yielding benefits, Mr. Craig said that it also has the potential to compromise an athlete’s recovery capabilities and performance.Exercising in a fasted state may place increased strain on the adrenal glands, potentially impairing the function of thyroid hormones and other anabolic processes, he added, noting that most fasting studies have been conducted on young, active males who possess physiological resilience and can adapt relatively easily to short-term challenges.
Each athlete is unique and may not derive the same benefits from fasted training. When working with clients, especially “over-enthusiastic amateurs or elite athletes,” the risk of adrenal fatigue must be taken seriously, Mr. Craig said. They may already experience compromised endocrine function, including the pituitary, adrenal, gonadal, and thyroid systems, which could be further exacerbated by a fasting regimen, leading to increased cortisol release in the absence of sufficient nourishment, he noted.
Why Women Must Approach With Caution
Fasted training is not universally suitable, especially for women, Candace Vermaak, who holds a doctorate in sport science and is a lecturer at the Stellenbosch University department of exercise, sport, and lifestyle medicine, told The Epoch Times.Women’s hormone profiles are more complex than men’s, Ms. Vermaak said. The menstrual cycle and, in severe cases, amenorrhea (the lack of a menstrual period) could add to the hormone imbalance. All of this makes women much more sensitive to inadequate nutrient intake, she noted.
Cortisol levels naturally peak in the morning, potentially exacerbated by intense fasted workouts, she said. This heightened cortisol release can lead to chronic elevation—particularly impactful for women—disrupting the delicate balance of sex hormone production.
Such disruption may impede not only athletic performance but also overall well-being by interfering with the regulation of estrogen and testosterone levels.
How to Make Your Training Work for You
Drawing from his decades of working with clients, Mr. Craig often recommends reintroducing a nourishing breakfast to those following a strict fasting regimen to support morning training sessions. This approach often helps optimize body composition, enhance training performance, and facilitate better recovery between exercise sessions.The word “intermittent” is often missing in the interpretation of intermittent fasting, Mr. Craig said. These approaches should be used intermittently, not all the time, depending on a person’s current health state, training patterns, stress levels, and genetic predispositions.
“We suggest that athletes train at relatively low intensities (and not at high intensity levels) when fasting to ensure that they recover adequately to optimize performances in competitive events,” the authors wrote.
Fasted training is an individualized endeavor requiring careful consideration of factors such as blood sugar levels, stress levels, sleep quality, and metabolic profile, Ms. Vermaak said. Prioritizing these assessments ensures optimal performance and well-being while mitigating potential risks associated with training in a fasted state.