The first six days at altitude require reduced work. That workload reduction is similar in impact to that afforded by sickness for athletes in very heavy training. In such situations athletes return to training and perform better even though they have been ill. It is doubtful that 21 days of altitude training leads to greater gains in training or performance capacity beyond those seen at sea-level. For the same category of sea-level work, altitude training will be at approximately 10 bpm higher.
All physiological parameters are stable.
Adjustments in training and performance and physiological parameters. The readjustment demands compromise performance. Training and performance are now enhanced and physiology is stable. The athlete has returned to being a sea-level trained individual. There were, however, possible trends that may explain the potential gains as a result of altitude training.