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Australian army recruits in training display symptoms of overtraining
Christine K Booth1, Bianka Probert, Chris Forbes-Ewan
1Human Performance Functional Group, Chemical Biological Radiological Nuclear Defence Centre, Defence Science and Technology Organisation, Scottsdale, Australia.
Abstract:
The proposition that the demands of recruit training, including physical and psychological stresses, result in symptoms of overtraining was investigated during the 45-day Army Common Recruit Training course. Body mass, physical fitness, fasting blood measures of immune status, hormones (serum free testosterone/cortisol ratio), inflammation, and iron status were measured at baseline and after weeks 5 and 6. Psychological measures of mood and fatigue and general health were measured at the end of each week. Sleep diaries were completed each evening and morning. Evidence for overtraining symptoms of fatigue, sleep disturbance, immune suppression, reduced iron status, high rates of minor injuries, and hormonal changes was found. However, recruits were not pushed so hard that physical performance deteriorated greatly. Accumulated sleep deprivation might be a major contributor to the adverse hormonal changes. We conclude that there was some evidence of recruits being overtrained.
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