Physiological and protector and scoring system (PSS) ımpact responses to 7 s repeated kicking in taekwondo athletes of different levels

To investigate PSS impact value and heart rate responses during short term high intensity loading, as well as post loading blood lactate concentration and heart rate recovery in taekwondo athletes of different performance levels. Nineteen male taekwondo athletes (10 international and 9 national level) participated. After three maximal impact tests with both legs using the Daedo Gen2 electronic body protector and scoring system (PSS), the athletes performed a 7-s repeated kicking protocol using Double Airborne Palding Chagi, starting with the right leg and alternating legs throughout the bout. PSS impact values and heart rate were recorded during the protocol, whereas blood lactate concentration and heart rate were measured at rest, before the protocol, and at 1, 3, and 6 min of recovery. Data were analysed using mixed-design ANOVA, linear mixed-effects models, and Welch's t -tests. Blood lactate concentration increased significantly after the 7-s test and remained elevated during recovery (F(2.16,36.64)=54.88, p <.001, ηp2 = 0.76, 90% CI [0.62, 0.82]). Heart rate during the recovery period was higher in national level athletes than in international level athletes (F(1,17)=7.69, p =.013, ηp2 = 0.31, 90% CI [0.04, 0.52]), whereas heart rate recovery was greater in international level athletes (HRR60: p =.037, Hedges' g = 1.52, 95% CI [0.51, 2.50]; HRR60%: p=.037, g = 1.54, 95% CI [0.52, 2.53]). Maximal kick impact differed across repeated trials (F(1.61,27.33)=11.62, p <.001, ηp2 = 0.41, 90% CI [0.15, 0.56]) but not between athlete levels (F(1,17)=0.75, p=.399, ηp2 = 0.04, 90% CI [0.00, 0.25]). Kick impact during the 7-s repeated-kicking protocol remained stable, with no significant order, group, or order × group effects (all p >.44). Short duration loading significantly increased blood lactate concentration in both groups, whereas international level athletes demonstrated greater heart rate recovery. In contrast, kicking impact performance was maintained throughout the 7 s repeated kicking protocol and did not differ between athlete levels. Future studies should examine these responses in larger and more diverse samples.