Table 1. Swimming time in test on exercise tolerance. Data are means (± SEM).

Groups	Control	CE (4 wk)	IHT (2 wk)	CE+IHT during the first two weeks	CE+IHT during the last two weeks
Endurance (min)	10.0 (2.0)	18.6 (1.7)*	32.4 (2.1) *,†	68.2 (1.5)*,†	63.9 (1.4) *,†

Abbreviations: CE= chronic exercise, HT= intermittent hypoxic training, CE+IHT= chronic exercise in combination with sessions of intermittent hypoxic training during the first or the last two weeks. * p < 0.05 compared with control group, † p < 0.05 between experimental groups.