Effects of two work-to-rest ratios on physiological, neuromuscular, and RPE responses during taekwondo-specific HIIT

To investigate the effects of different work: rest (W: R) ratios on physiological, neuromuscular, and rating of perceived exertion (RPE) responses during taekwondo-specific high-intensity interval training (HIIT).

Thirteen moderate-trained taekwondo athletes completed a familiarization session and two HIIT trials which consisted of three rounds of 2 min roundhouse kicks with 1 min of rest in between. The W: R ratio protocols were: 1:0.5 (10s:5s) and 1:5 (10s:50s). Heart rate (HR) and oxygen uptake (VO₂) were continuously determined throughout the trials. Blood lactate concentration ([La^-]), countermovement jump (CMJ), and RPE were recorded before trials and after each round. The estimated contribution of the energy systems was calculated for each round.

In the two W: R ratio protocols, HR, [La^-], and RPE progressively increased across rounds (P < 0.001, 0.700 <[Formula: see text] < 0.868). The relative aerobic energy contribution significantly increased ( P < 0.001, [Formula: see text] = 0.488), while the relative glycolytic energy contribution significantly decreased in round 3 (P < 0.001,[Formula: see text] = 0.536). Compared to 1:0.5 W: R ratio, the 1:5 W: R ratio induced lower HR, VO₂, and RPE (P < 0.001, 0.230 <[Formula: see text] < 0.659).

Physiological and RPE responses progressively increased with round during taekwondo-specific HIIT. The 1:0.5 W: R ratio induced greater physiological responses and RPE than 1:5 W: R ratio, thereby providing critical insights for the optimization of taekwondo-specific HIIT program design.