What is the level of evidence for the impact of respiratory exercises on athletic performance?

From the Guidelines

Respiratory exercises have a moderate level of evidence supporting their impact on athletic performance.

Key Findings

• The evidence suggests that respiratory exercises, such as those used in altitude/hypoxic training, can improve athletic performance by increasing total haemoglobin mass and enhancing VO2max 1.
• However, the response to hypoxic training can be highly variable and may depend on factors such as sex, training status, and initial haemoglobin mass level 1.
• Respiratory muscle training, such as that used in pulmonary rehabilitation, can also improve exercise performance by increasing ventilatory endurance and reducing the sensation of breathing effort or work 1.
• The mechanisms underlying the perception of breathing effort or work are complex and involve a combination of respiratory muscle afferents, perceived cortical motor command, and corollary discharge 1.

Respiratory Exercises and Athletic Performance

• Altitude/hypoxic training can improve athletic performance by stimulating erythropoiesis and increasing total haemoglobin mass, leading to enhanced VO2max and competitive performance 1.
• Respiratory muscle training can improve exercise performance by increasing ventilatory endurance and reducing the sensation of breathing effort or work, allowing athletes to perform at a higher intensity for longer periods 1.
• The evidence suggests that respiratory exercises can be a useful adjunct to traditional training methods for athletes, particularly those competing in endurance events 1.

Limitations and Future Directions

• The response to hypoxic training can be highly variable and may depend on factors such as sex, training status, and initial haemoglobin mass level, highlighting the need for individualized training programs 1.
• Further research is needed to fully understand the mechanisms underlying the perception of breathing effort or work and to develop more effective respiratory training programs for athletes 1.

From the Research

Level of Evidence

The level of evidence for the impact of respiratory exercises on athletic performance is based on several studies that have investigated the effects of respiratory muscle training (RMT) on sport performance and respiratory muscle strength and endurance 2, 3, 4, 5, 6.

Key Findings

• A systematic review with meta-analyses found that RMT can improve sport performance, including time trials, exercise endurance time, and repetitions on Yo-Yo tests 2.
• A narrative review found that voluntary breathing strategies, such as slow breathing, can benefit athletes by improving cardiovascular fitness, reducing stress and anxiety, and improving overall health and well-being 3.
• A study on wheelchair basketball players found that inspiratory muscle training improved respiratory function, but did not significantly improve repetitive sprint performance 4.
• A review of respiratory physiology found that the pulmonary system may become a limiting factor to exercise at sea level and altitude, and that highly trained athletes may develop respiratory muscle fatigue and exercise-induced hypoxaemia 5.
• A review of respiratory muscle training in healthy humans found that specific training modes, such as voluntary isocapnic hyperpnea, flow resistive loading, and pressure threshold loading, can improve specific aspects of respiratory muscle function and exercise performance 6.

Study Limitations

• The studies had varying sample sizes, RMT protocols, and outcome measures, which may limit the generalizability of the findings 2, 4.
• The mechanisms by which RMT improves exercise performance are unclear, and further research is needed to fully understand the effects of RMT on athletic performance 6.