Differences between anthropometric indicators and the impact force of taekwondo kicks performed with the dominant and non-dominant limb

Study aim: Taekwondo is known for its very dynamic sports fighting, in which the athletes perform strikes mainly with their lower limbs. The aim of the study was to compare the differences between the impact force of strikes performed with the dominant and non-dominant limbs and its correlation with anthropometric indicators. Material and methods: Six elite Olympic taekwondo players took part in the research (20.0 +/- 3.2 years, 185.0 +/- 8.5 cm, 75.3 +/- 10.9 kg). Body composition including body mass, percent of body fat (FATP), fat mass (FATM), fat-free mass (FFM) and muscle mass (MM) was determined by bioelectric impedance analysis. Maximal strike impact force (F-max) and F-max relative to FFM (F-max . FFM-1) of roundhouse kick (dollyo chagi) and side kick (yop chagi) were measured using a dynamometric punching bag with an embedded accelerometer. Results: We found significant differences between the dominant limb (DL) and non-dominant limb (NL) in anthropometric analysis: FATP was 10.52 +/- 5.38 % and 11.32 +/- 4.83 %, FFM was 11.87 +/- 0.97 kg and 11.43 +/- 1.09 kg, MM was 11.25 +/- 0.92 kg and 10.82 +/- 1.02 kg for DL and NL respectively. In dollyo chagi F-max and F-max . FFM-1 were higher for DL than NL and were 2733 +/- 748 N and 2206 +/- 778 N, 41.34 +/- 8.16 N . kg(-1) and 33.29 +/- 9.02 N . kg(-1) respectively. Yop chagi has a lower impact force compared to dollyo chagi. F-max and F-max . FFM-1 for DL and NL were 1763 +/- 303 N and 1779 +/- 372 N, 26.76 +/- 3.07 N . kg(-1) and 26.9 +/- 3.57 N . kg(-1) respectively. We found a significant correlation between F-max in yop chagi and FFM (R = 0.83, p < 0.05). Conclusions: Athletes should fight using a stance where the dominant limb is moved further away from the target in order to strike with maximum force.