Physiological, Mechanical, and Perceptual Responses to Comparing 7.5% and 10% Body Mass Load during the Cycling Sprint Interval Exercise in Physically Active Men

Abstract

The aim of the study was to verify changes in peak power output (PPO), acid-base balance, blood lactate (La−) accumulation, and oxygen uptake (VO2) whilst applying a 7.5% and 10% load of the participant’s body mass in a cycling sprint interval exercise (SIE) (two series consisting of 3 × 10 s efforts “all-out” separated by a 30 s active break). Twelve healthy, physically active men with maximal oxygen uptake (VO2max = 52.4 ± 7.8 mL∙kg−1∙min−1) were included in the study and performed two cross-over SIE sessions, with a load of 7.5% of the participant’s body mass (SIE7.5%) and 10% of the participant’s body mass applied (SIE10%). The physiological, mechanical, and perceptual responses were assessed during and after each session. After SIE10%, a 10.3% higher and 25.5% faster PPO time was obtained, with no significant differences in La−, a lower physiological cost (mean oxygen uptake and mean heart rate), faster restitution of VO2 and heart rate, and a lower rate of perceived exertion. Therefore, a 10% load of the participant’s body mass during 10 s effort induced greater physiological adaptations and mechanical responses, which may promote the use of a higher workload in sprint interval training to improve physical performance.