Influence of exercise modality and modality-specific training on endurance exercise performance in hypoxia
Date
2017
Authors
Theisen, Jeremy Kenneth, author
Bell, Christopher, advisor
Dinenno, Frank, committee member
Kanatous, Shane, committee member
Journal Title
Journal ISSN
Volume Title
Abstract
INTRODUCTION: In hypoxia, endurance exercise performance is impaired. The magnitude of impairment may be variable between individuals and exercise modalities. The purpose of this study was to determine the influence of exercise modality and modality-specific training on hypoxia-mediated performance decrements. METHODS: In a randomized cross-over design, endurance trained cyclists (4 males, 3 females) and rowers (5 males, 3 females) performed exercise on both cycling and rowing ergometers. On separate occasions, participants completed graded exercise tests in normoxia (FiO2= 0.21), and standardized exercise (15 minutes, 100 W) and time trials (4 km cycling, 2 km rowing) in normoxia and hypoxia (FiO2= 0.15). RESULTS: Hypoxia-mediated performance decrements were not different between cyclists and rowers (17±1 vs. 18±1%, p=0.189), cycling and rowing (18±2 vs. 16±2%, p=0473), or any combination of training or test modality (p=0.138). In rowers, peripheral oxygen saturation (SpO2) was lower at the end of rowing compared to cycling time trials (78±1 vs. 83±1%, p=0.002), and lower than that of cyclists at the end of rowing time trials (78±1 vs. 83±1%, p<0.001). DISCUSSION: Hypoxia-mediated performance decrements were not different between training modalities, test modalities, or any combination of the factors. We speculate that reduced SpO2 in rowers at the end of rowing time trials may be related to a greater active muscle mass, causing a rightward shift in the oxyhemoglobin dissociation curve and reduced transit time of blood in pulmonary capillaries. In conclusion, SpO2 may be related to active muscle mass during exercise and could potentially modulate performance in hypoxia.