Hypoventilation training is a physical training method in which periods of exercise with reduced breathing frequency are interspersed with periods with normal breathing. The hypoventilation technique consists of short breath holdings and can be performed in different types of exercise: running, cycling,swimming, rowing, skating, etc.
Generally, there are two ways to carry out hypoventilation: at high lung volume or at low lung volume. At high lung volume, breath holdings are performed with the lungs full of air (inhalation then breath hold). Conversely, during hypoventilation at low lung volume, breath holdings are performed with the lung half full of air. To do so, one has to first exhale normally, without forcing, then hold one’s breath. This is called the exhale-hold technique.
The scientific studies have shown that only hypoventilation at low lung volume could lead to both a significant decrease in oxygen (O2) concentrations in the body and an increase incarbon dioxide concentrations (CO2).
After several weeks of hypoventilation training, physiological adaptations occur that delay the onset of acidosis during a maximal exertion test. The studies have shown that at a given workload, pH and blood bicarbonate concentrations were higher, whereas lactate concentrations had a tendency to decrease. The reduction in acidosis would be due to an improvement in buffer capacity at the muscle level.