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bioRxiv · 10.1101/856237

Relationship between maximal incremental and high-intensity interval exercise performance in elite athletes

Chang, S.-C.·Adami, A.·Lin, H.-C.·Lin, Y.-C.·Chen, C. P. C.·Fu, T.-C.·Hsu, C.-C.·Huang, S.-C.
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Abstract

It remains unclear whether the number of total bouts to limitation (Blim) in high-intensity interval testing (HIIT) differs among individuals, no matter if performed at the same relative intensity. This study aimed to explore the physiologic factors determining tolerance to effort during a HIIT. Forty-seven female participants (15-28 years old) were included: 23 athletes from Taiwan national or national reserve teams, and 24 moderately-active female. Each participant underwent maximal incremental (INC; modified-Bruce protocol) cardiopulmonary exercise testing and HIIT on treadmill, on separate days. HIIT protocol alternated a 1-min effort at 120% of the maximal speed and the same slope reached at the end of INC, with a 1-min rest, until volitional exhaustion. Gas-exchanges, and muscle oxygenation at right vastus lateralis by near-infrared spectroscopy, were continuously recorded. Additionally, bioelectrical impedance was utilized for body composition analysis. The result showed that Blim differed greatly (range: 2.6 to 12) among participants. Stepwise regression revealed that Blim was determined primarily by oxygen consumption (VO2) and heart rate (HR) at second-minute recovery; and, muscle tissue saturation index at peak of INC (R=0.644). Also, age and percent body fat were linearly correlated with Blim (adjusted R=-0.475, -0.371, p<0.05). Therefore, HIIT performance is determined by fast recovery of VO2 and HR, rather than maximal VO2 or muscle oxygenation recovery. Moreover, capacity to sustain a HIIT declines with age since as early as late adolescent. Further investigations on which factors should be manipulated to further improve athletes performance are warrant.

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Chang, S.-C., Adami, A., Lin, H.-C., Lin, Y.-C., Chen, C. P. C., Fu, T.-C., Hsu, C.-C., Huang, S.-C.. 2019-11-26. Relationship between maximal incremental and high-intensity interval exercise performance in elite athletes. https://doi.org/10.1101/856237

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