When doing intensive exercise, oxygen is used by the body at a greater rate and free radicals start to be produced more quickly. This can make it difficult for the body to keep up by producing enough antioxidants to counteract the negative effects. When antioxidants are not sufficient to target free radicals this is referred to as oxidative stress. As a result, there could be some damage to muscles or inflammation could occur. However, since hydrogen is known to have antioxidant properties, there is a reason to believe that hydrogen-rich water (HW) could be beneficial for athletes by reducing muscle fatigue from oxidative stress.
In order to evaluate the effectiveness of hydrogen water for athletes, ten 19-22 year old male football players took part in exercise tests and blood sampling. Some of the participants were given hydrogen water (HW) while the others were given placebo water (PW) over a period of one week; the type of water given to each person was decided at random and not known by any of the participants. This was then repeated over a second week, with a new random selection being made for each person. Each participant drank the same volume of water at the same times before and during the day of the test. The men each completed 100 repetitions of maximal isokinetic knee extension. During this, peak torque and knee joint position were measured. In order to calculate the level of muscle fatigue, electrodes were used to record the electrical activity of the rectus femoris (a muscle located in the thigh). Each man had taken part in daily training sessions up to the day before the experiment.
Indicators of oxidative stress found in the blood were measured for all of the participants. Creatine kinase is an enzyme which is released into the blood in large amounts in the case of muscle damage; laboratory tests were carried out to measure the levels of this enzyme. This would help to ascertain the effectiveness of each type of water in providing antioxidants to prevent oxidative stress, that could otherwise lead to muscle damage.
The results show that HW lessened the increase of blood lactate levels and prevented the decrease of peak torque after exercise, which is otherwise an indicator of muscle fatigue. Therefore, HW helped to improve post-exercise muscle fatigue. This experiment has helped to show that hydrogen water can provide an effective source of hydration for athletes when undergoing exercise.