Study: endurance sport requires acid-base balance

The acid-base balance is essential for regulatory capacity. It continuously maintains the perfect balance between acids and bases, thereby ensuring that all metabolic processes can take place under ideal pH conditions. But sometimes the control system can be challenged. According to a recent study, intensive endurance sports can temporarily disrupt the perfect balance and cause metabolic stress.

The 2019 publication investigated the effects of intensive running training on the pH value. Nine athletes completed sprint training under either hypoxic (oxygen deficiency) or normoxic (normal oxygen supply) conditions. The intensive interval endurance exercises consisted of 10 three-minute runs at 90% maximum oxygen intake alternating with 60-second intensity breaks (lower intensity runs at 50% of maximum oxygen intake). Venous blood was taken from the subjects before the training session and during afterloading. It was shown that endurance training under moderate hypoxia (e.g. during classical altitude training) led to acidification of the blood. The running speed of these subjects was clearly below that of those running under normoxic conditions. Endurance training under hypoxic conditions thus led to a temporary shift in the blood pH and thus high metabolic stress.