How do hormones impact fitness performance?

From the Guidelines

Hormones play a crucial role in regulating fitness performance, with testosterone, growth hormone, and insulin-like growth factor-1 (IGF-1) promoting muscle protein synthesis and strength gains, while cortisol can break down muscle tissue if chronically elevated. According to a study published in the Annual Review of Medicine 1, testosterone therapy can lower voice pitch, change body composition, and increase libido in trans men, with significant improvements in muscle strength and performance. Another study published in the Annals of Internal Medicine 1 found that testosterone treatment improved erectile function and physical function in men, although the effects on muscle strength and endurance were less clear.

Key factors that influence hormone function and fitness performance include:

• Consistent sleep patterns (7-9 hours nightly) to regulate hormonal balance
• Stress management through meditation or deep breathing to minimize cortisol release
• Adequate protein intake (1.6-2.2g per kg of bodyweight daily) to support muscle growth and repair
• Incorporation of both resistance training and cardiovascular exercise to optimize hormone function and fitness performance
• Avoidance of overtraining, which can disrupt hormonal balance and negatively impact performance

It is essential to note that hormone replacement therapy or performance-enhancing drugs like anabolic steroids can carry significant health risks and are often prohibited in competitive sports. Natural hormone optimization through lifestyle factors provides sustainable performance benefits without the associated risks. A study published in Sports Medicine 1 highlighted the importance of energy availability and hormonal balance in female athletes, with low energy availability leading to hormonal disturbances, including decreased estradiol, progesterone, and insulin-like growth factor-1, and increased cortisol and ghrelin.

In terms of specific recommendations, athletes should prioritize a balanced diet, adequate sleep, and stress management to support optimal hormone function and fitness performance. Additionally, athletes should be aware of the potential risks of low energy availability and hormonal imbalances, and take steps to prevent them, such as monitoring energy intake and output, and seeking medical attention if symptoms persist. By prioritizing natural hormone optimization and a balanced lifestyle, athletes can achieve sustainable performance benefits while minimizing the risks associated with hormone dysfunction.

From the FDA Drug Label

14 CLINICAL STUDIES 14. 1 Clinical Study in Hypogonadal Males

Testosterone gel was evaluated in a randomized multicenter, multi-dose, active and placebo controlled 90-day study in 406 adult males with morning testosterone levels ≤300 ng/dL.

The FDA drug label does not answer the question.

From the Research

Hormones and Fitness Performance

Hormones play a significant role in fitness performance, with various studies examining their impact on athletic ability. The effects of hormones such as growth hormone (GH) and testosterone on exercise capacity, muscle strength, and body composition are crucial areas of research.

Growth Hormone and Fitness Performance

• Growth hormone has been shown to increase exercise capacity, with measures such as maximal oxygen uptake (VO2max) and ventilatory threshold (VeT) improving in GH-deficient adults who receive GH replacement 2.
• However, the administration of supraphysiologic doses of GH to athletes may not necessarily translate to improved athletic performance, with some studies suggesting that it may even worsen exercise capacity and increase adverse events 3.
• The effects of GH on skeletal muscle mass, strength, and fiber composition are also unclear, with some studies suggesting that GH administration alone or in combination with strength exercise has little effect on muscle volume, strength, and fiber composition in non-GH-deficient healthy young individuals 4.

Testosterone and Fitness Performance

• Testosterone is an important modulator of muscle mass in both men and women, with acute increases in testosterone induced by resistance exercise 5.
• Testosterone supplementation has been shown to improve body composition and muscle performance in older men, with significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance 6.
• The interaction between testosterone and the intracellular androgen receptor (AR) is crucial for the physiological signals from testosterone, with the response of testosterone and AR to resistance exercise determined by upper regulatory elements including the acute exercise programme variable domains, sex, and age 5.

Combined Effects of Hormones on Fitness Performance

• The combined effects of testosterone and GH on fitness performance have also been studied, with supplemental testosterone producing significant gains in total and appendicular lean mass, muscle strength, and aerobic endurance, and outcomes appearing to be further enhanced with GH supplementation 6.
• However, more research is needed to conclusively determine the effects of hormones on athletic performance, with the current evidence suggesting that claims that growth hormone enhances physical performance are not supported by the scientific literature 3.