HYPO WHAT?

2) A short history: from Zátopek to now

(From the book "Hypoventilation training, push your limits",  Xavier Woorons, 2014, 166p.)

1950's: The Eastern runners' practises

In the middle of the 20^th century, runners from Eastern Europe and former USSR often trained by voluntarily restricting breathing frequency. The most famous of them was Emil Zátopek, the Czech long-distance runner, 4 times Olympic gold medallist between 1948 and 1952, who broke 18 world records. During his training, Zatopek regurlary held his breath for as long as possible to strengthen his pulmonary capacity and to simulate the conditions of competition. Once, he held his breath for so long that he lost consciousness. In an era of empirical practice, whether such practice was really effective was unknown, but when performed to such extremes, it was probably not fully safe for athletes.

1970's: A new training method in swimming

From the Olympic Games of Mexico in 1968 (altitude: 2200 m), training with restricted breathing became of greater interest. Indeed, during the Games, the altitude-induced lower O2 concentrations led to a drop in performances in middle and long distance trials. Consequently, the goal was to find ways to enhance O2 utilization at the muscular level in order to increase performance at altitude or at sea level. In the early 1970's, one of the greatest swimming trainers, the American James Counsilman, hypothesized that swimmers could decrease O2 supply to the muscles and could simulate an altitude training if they voluntarily breathed less frequently during their training. Thus, during the 1970’s, training with restricted breathing, classically called “hypoxic training”, became very popular in the World of Swimming. In each training session, a great number of swimmers included exercises in which they had to inhale every 5, 7 or 9 arm strokes instead of the 2-3 single arm strokes as usually performed.

1980's: The application by middle distance runners

In the 1980's, while there was still a lot of enthusiasm for training with restricted breathing in swimming, hypoventilation training practices emerged in athletics. This kind of training was supported by the Brazilian coach Luiz De Oliveira, who trained Joaquim Cruz, the 1984 olympic champion of the 800m in Los Angeles, and Marie Decker, the world champion of the 1500m and 3000m in 1983 in Helsinki. De Oliveira often asked his athletes to perform  exercises with breath holding once a week. These exercises consisted of running without breathing over several dozen meters or to hold one's breath in the last 30 m of the training series in order to simulate fatigue that occurs during competition. Although applied more rationally than by the Eastern runners of the 1950’s, this kind of training was still not based on solid scientific knowledge.

1980's-1990's: The first scientific works

The first scientific works on training with restricted breathing in swimming or running were mainly published from the 1980’s. The results of the studies contradicted the hypotheses put forward by the World of Sport and challenged this kind of training. Indeed, the studies demonstrated that while exercise with restricted breathing increased CO2  concentrations in the body, it did not significantly reduce O2 concentrations. Despite these conclusions, training with restricted breathing continued to be widely applied by swimmers in the following years and became a classical training method, still often called (erroneously) “hypoxic training”.

2000-2010: Hypoventilation: the new formula!

In the 2000's, new scientific studies were undertaken by the laboratory "Cellular and functional responses to hypoxia" of Paris 13 University to propose a new approach to hypoventilation training. Xavier Woorons, a french researcher, expert in exercise physiology, hypothesized that a significant decrease in blood oxygenation could occur if breath holdings were performed with a reduced amount of air in the lungs. So far, hypoventilation had always been carried out at high lung volume, that is with lungs full of air during the breath holds. The results of the scientific studies were very encouraging. They showed that hypoventilation at low lung volume (i.e "exhale-hold" technique) could significantly reduce the O2 concentrations both in the blood and in the muscles during different forms of exercise (cycling, running, swimming). Without leaving sea level and without using expensive and heavy devices, it was possible to train virtually at an altitude above 2000 meters! To test the effectiveness of the method, runners were asked to train for 4 weeks by applying the exhale-hold technique. At the end of the training period, hypoventilation induced physiological adaptations that delayed the onset of fatigue and improved performance in most of the runners.

2015: Today

                                                                                                                                     To date, on the basis of the studies carried out over these last few years, it is possible to conclude that hypoventilation training at low lung volume is advantageous in sports requiring continuous or intermittent intense efforts. It represents an innovative training method (or physical preparation method) that can be used by many athletes, in many different disciplines.