Abstract
Hypobaric hypoxia (HH) limits oxygen supply to tissues and increases metabolic demands, especially during exercise. We studied the influence of HH exposure on the subcutaneous adipose tissue (SAT) thickness and circulating metabolic-related cytokines levels after a resistance training (RT) program. Twenty trained men participated in a traditional hypertrophy RT for 8 weeks (three sessions/week) under intermittent terrestrial HH (2320 m) or normoxia (N, 690 m) conditions. Before, at week 6, and after the RT, SAT, and vastus lateralis (VL) muscle thickness were measured by ultrasound. Blood samples were taken to analyse serum cytokines (IL-6, IL-15, irisin, and myostatin) by multiplex immunoassay. Our findings revealed a moderate reduction in IL-6 and irisin in HH following the RT (ES < -0.64; p < 0.05). Additionally, RT in HH promoted serum IL-15 release (ES = 0.890; p = 0.062), which exhibited a trivial inverse association with the reductions observed on SAT (-17.69%; p < 0.001) compared with N. RT in HH explained ~50% of SAT variance (p < 0.001). These results highlight the benefit of stressor factors linked to RT in HH on SAT through the modulation of serum metabolic cytokine profiles, suggesting a potential effect on overall body composition.