Introduction
Leg training, particularly through compound movements like squats and deadlifts, is often promoted for its potential to raise testosterone levels. This article examines the scientific evidence behind that claim, looking at both the immediate and long-term hormonal effects of lower-body resistance training.
Mechanisms of Hormonal Response to Leg Training
Acute Hormonal Responses
High-intensity lower-body exercises activate large muscle groups, leading to notable hormonal changes. A study published in the Journal of Strength and Conditioning Research found that squats caused a greater immediate increase in testosterone and growth hormone compared to leg presses. This is likely due to the increased muscle recruitment and physical demand involved in squatting.
Influence of Exercise Modality
The mode of exercise plays a critical role in hormonal response. Free-weight movements like squats tend to produce stronger hormonal effects than machine-based alternatives. This is due to the higher level of stabilisation and full-body engagement required when using free weights.
Impact on Testosterone Levels
Acute Increases
Research consistently shows that lower-body resistance training can cause temporary spikes in testosterone. These increases are typically observed immediately after training and are influenced by workout intensity, volume, and rest periods. For example, performing six sets of ten squats at high intensity has been shown to significantly raise testosterone levels for a short period.
Long-Term Effects
The long-term impact of leg training on resting testosterone levels is less conclusive. Some studies suggest that consistent resistance training may lead to modest increases in baseline testosterone over time. However, these changes are typically small and depend on variables such as age, training experience, and general health.
Additional Benefits of Leg Training
- Increased muscle mass and strength: Regular leg training supports overall hypertrophy and power development.
- Improved metabolic health: Large compound movements improve insulin sensitivity and raise metabolic rate.
- Hormonal balance: Beyond testosterone, leg training also influences hormones such as growth hormone and cortisol, contributing to better overall hormonal regulation.
Potential Drawbacks
- Risk of overtraining: Excessive volume or intensity without adequate rest can lead to hormonal disruption and a higher risk of injury.
- Technical demands: Compound exercises like squats require proper technique. Poor form can lead to injury, especially under heavy loads.
Conclusion
Leg training, especially with free-weight compound movements like squats, can cause significant acute increases in testosterone. While these hormonal spikes are short-lived, regular lower-body resistance training offers broader benefits including improved muscle mass, better metabolic function, and healthier hormonal balance. To maximise the benefits and minimise risks, leg training should be performed with proper form and balanced with sufficient recovery.