Altitude Training, Blood Doping, and Overtraining | CSCS Chapter 6

Aerobic training adaptations are significantly influenced by external factors including altitude, blood doping, and overtraining. Training at altitude triggers acute physiological stress, such as elevated heart rates, before chronic adaptations like increased red blood cell production occur; the "live high, train low" model remains the most effective strategy for performance gains. While blood doping and erythropoietin (EPO) artificially enhance oxygen delivery by increasing hematocrit levels, these practices are illegal and carry severe health risks, including fatal cardiac events. Furthermore, overtraining syndrome—often characterized by hormonal imbalances like a decreased testosterone-to-cortisol ratio, glycogen depletion, and persistent performance declines—underscores the necessity of adequate recovery. Individual performance potential is further constrained by genetic predispositions, age-related declines in VO2 max, and biological sex differences, which collectively dictate the scope of an athlete's physiological adaptation window.