Altitude training
[1][2] Depending on the protocols used, the body may acclimate to the relative lack of oxygen in one or more ways such as increasing the mass of red blood cells and hemoglobin, or altering muscle metabolism.
Some athletes live permanently at high altitude, only returning to sea level to compete, but their training may suffer due to less available oxygen for workouts.
Athletes or individuals who wish to gain a competitive edge for endurance events can take advantage of exercising at high altitude.
Studies examining the live-high, train-low theory have produced varied results, which may be dependent on a variety of factors such as individual variability, time spent at high altitude, and the type of training program.
[13] Good venues for live-high train-low include Mammoth Lakes, California; Flagstaff, Arizona; and the Sierra Nevada, near Granada in Spain.
[16] Exposure to extreme hypoxia at altitudes above 16,000 feet (5,000 m) can lead to considerable deterioration of skeletal muscle tissue.
A greater level of PCr resynthesis augments the muscles power production during the initial stages of high-intensity exercise.
Athletes are able to perform high intensity training at lower velocities and thus produce less stress on the musculoskeletal system.
[16] This is beneficial to an athlete who had a musculoskeletal injury and is unable to apply large amounts of stress during exercise which would normally be needed to generate high intensity cardiovascular training.
[21] The physiological adaptation that is mainly responsible for the performance gains achieved from altitude training, is a subject of discussion among researchers.
Some, including American researchers Ben Levine and Jim Stray-Gundersen, claim it is primarily the increased red blood cell volume.
[25] It is uncertain how long this adaptation takes because various studies have found different conclusions based on the amount of time spent at high altitudes.
Over the past thirty years, EPO has become frequently abused by competitive athletes through blood doping and injections in order to gain advantages in endurance events.
[23] This efficiency can arise from numerous other responses to altitude training, including angiogenesis, glucose transport, glycolysis, and pH regulation, each of which may partially explain improved endurance performance independent of a greater number of red blood cells.
[5] Furthermore, exercising at high altitude has been shown to cause muscular adjustments of selected gene transcripts, and improvement of mitochondrial properties in skeletal muscle.
[27][28] In a study comparing rats active at high altitude versus rats active at sea level, with two sedentary control groups, it was observed that muscle fiber types changed according to homeostatic challenges which led to an increased metabolic efficiency during the beta oxidative cycle and citric acid cycle, showing an increased utilization of ATP for aerobic performance.
