Co‐administration of Neptazane and aminophylline to men abrogates the decline in endurance exercise performance in simulated high‐altitude (708.6)

During a sojourn to high altitude, endurance exercise performance is diminished; pharmacotherapy may abrogate this performance deficit. We hypothesized oral administration of Neptazane (N), Aminophylline (A), and/or N combined with A would attenuate hypoxia‐mediated decrements in endurance exercise performance in humans. Healthy males (26±1 years, body mass index: 24.9±0.4 kg/m 2 ; mean±SE) were randomly assigned to one of four treatments: placebo ( n =9), N (250 mg; n =10), A (400 mg; n =9), or N (250 mg) combined with A (400 mg; n =8). On two separate occasions, the first in normoxia (21% O 2 ) and the second in hypoxia (15% O 2 ), participants sat for 4.5 hours before completing a standardized exercise bout (30 min, stationary cycling, 100 W) followed by a time trial (time to cycle 12.5 km). The magnitude of time trial performance decrement in hypoxia did not differ ( P >0.09) between placebo (+3.0±1.0 min), N (+1.4±0.5 min) and A (+1.8±0.4 min), however the performance decrement with N combined with A was less than placebo (+0.6±0.5 min; P =0.01). This improvement may have been partially mediated by increased SpO 2 in hypoxia with N combined with A, compared with placebo (73±1 vs . 79±2%; P <0.02). In adult men, N combined with A abrogated the hypoxia‐mediated decrement in endurance exercise performance. Co‐administration of N and A may promote endurance exercise performance during a sojourn to high altitude. Grant Funding Source : Supported by DARPA: N66001‐10‐C‐2134