Validity and reliability of the session-RPE method for quantifying training load in karate athletes

Aim. Aim of the study was to test the construct validity and reliability of the session rating of perceived exertion (sRPE) method by examining the relationship between RPE and physiological parameters (heart rate: HR and blood lactate concentration: [La]) and the correlations between sRPE and two HR-based methods for quantifying internal training load (Banister's method and Edwards's method) during karate training camp. Methods. Eighteen elite karate athletes: ten men (age: 24.2 +/- 2.3 years, body mass: 71.2 +/- 9 kg, body fat: 8.2 +/- 1.3% and height: 178 7 cm) and eight women (age: 22.6 +/- 1.2 years, body mass: 59.8 +/- 8.4 kg, body fat: 20.2 +/- 4.4%, height: 169 4 cm) were included in the study. During training camp, subjects participated in eight karate-training sessions including three training modes (4 tactical-technical, 2 technical-development, and 2 randori training), during which RPE, HR, and [La-] were recorded. Results. Significant correlations were found between RPE and physiological parameters (percentage of maximal HR: r=0.75, 95% CI=0.64-0.86; [La-]: r=0.62, 95% CI=0.49-0.75; P<0.001). Moreover, individual sRPE was significantly correlated with two HR-based methods for quantifying internal training load (r=0.65-0.95; P<0.001). The sRPE method showed the high reliability of the same intensity across training sessions (Cronbach's alpha=0.81, 95% CI=0.61-0.92). Conclusion. This study demonstrates that the sRPE method is valid for quantifying internal training load and intensity in karate.