SPURIOUS ALTITUDE TRAINING EFFECTS IN SWIMMERS
Pyne, D. B. (1998). Performance and physiological changes in highly trained swimmers during altitude training. Coaching and Sport Science Journal, 3, 42-48.
Studies on the effects of altitude training have been historically plagued by poor or unacceptable research designs. This article continues with that traditional deficiency. It contains no matched or control group that allows confounding variables to be discounted. So many factors existed in both exposures to a training camp ("overseas holiday") that it is implausible to attribute any noted changes to altitude acclimatization alone.
Observations were made of volunteers from the Australian National Swimming Team on trips to Flagstaff, Arizona (6,900 feet) for three-week camps in May, 1995 and 10 months later in March 1996. In the second camp, 15 of the original 22 swimmers from the first camp repeated the experience.
At both camps both gender groups lost body mass. In the first camp performers improved their 200 m times at altitude and also decreased heart rate and blood lactate at a given swimming velocity. Creatine kinase decreased in females and uric acid increased in males. In the second camp 200 m time at altitude improved again but there were no changes in heart rate or blood lactate at particular velocities.
The 200-m times of second-camp swimmers before leaving Australia and 10 days after leaving altitude improved in 19 of 22 swimmers. This group improvement, representing a single uncontrolled observation, could easily represent a "rest effect" derived from days 1-5 of altitude acclimatization and days 21-24 of recovery rather than an altitude effect. An attribution to altitude benefits is indefensible and since it is based on a single observation cannot be generalized even if it was accurate.
In "pre-experiments", the actual name given to data gathered according to the format used in Pyne's paper, any number of causes could be proposed with equal plausibility to altitude and rest effects. Some other possible causes are: the stimulation of the training camp, inspiration of training with a group of motivated athletes and coaches, input from coaches other than the home coach, increase in self-esteem gained from being on an international travelling team, controlled eating and training environment, increased fitness, regular rest and recovery sessions throughout the camp, regular testing and monitoring that heightens performance feedback and the importance of training, and weight-loss and body composition changes.
A striking feature of the study is that physiological changes related to performance were only observed in the first camp. But, performance changes occurred at altitude. This implies that performance improvements at altitude are not related to physiological changes since none were observed on the second occasion. The only consistent finding was that altitude performances improved while training at altitude, a phenomenon that is already well-accepted in the scientific arena.
Any interpretation of this study must be conservative and skeptical. It shows that descriptions of altitude training camps of this type can only report what occurred and are not the basis for implying why observations occurred.
Implication. This article does not provide evidence that supports the benefit of altitude training camps other than to show that training at altitude improves altitude performances. It does not provide evidence that altitude training improves sea level performances in elite swimmers.
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