The simulation effects of mountain climbing training on selected endocrine responses

The simulation effects of mountain climbing exercise training on plasma testosterone, cortisol and luteinizing hormone (LH) levels were examined in ten recreational mountain male climbers. Subjects underwent a simulating mountain climbing exercise training 3 times a week for a total of eight weeks before an expedition to Mount Muztag Ata (7546 m, Xingian, China). During training, each subject carried a 40 kg back pack while walking on a treadmill at a speed of 1.9 mph for 60 min at sea level. Subjects completed an incremental treadmill test to exhaustion prior to training, after training, and one week after returning from Mount Muztag Ata. Blood samples were collected from antecubital vein at rest and at 5, 60, and 120 min post testing to determine the plasma testosterone, cortisol and LH levels. The basal plasma testosterone and cortisol concentrations were lower in both post-training and after-climbing conditions compared with that in the pre-training condition (p<0.01). The basal plasma LH concentration was remained unchanged after training and after the mountain climbing compared with levels measured in the pre-training phase. No correlation could be established between plasma LH and testosterone level. These results suggest that an eight-week period of mountain climbing training protocol may be beneficial in maintaining normal endocrine function during and after high altitude mountain expedition. Our results also indicate the decrease of plasma testosterone was LH independent.