Baseline physiological and kinanthropometric data were collected for 11 male and 12 female elite taekwon-do athletes from the Czech national team for evaluation of anthropometry, aerobic and anaerobic capacities, strength, visual reaction time, pulmonary function, flexibility and explosive power of the lower limbs (vertical jump). Both male and female taekwon-do black belts demonstrated low adiposity (8.2 and 15.4% fat, BMI 21.9 and 22.0 kg m^-2, respectively), normal reactivity and pulmonary function, above average muscular strength, PWC-170 (3.4 vs 2.7 W kg^-1) and aerobic power (54 vs 42 ml min^-1 kg^-1), and a high flexibility (37 and 38 cm) and anaerobic performance (peak power output from a 30 s Wingate test = 14.7 and 10.1 W kg^-1; anaerobic capacity = 334 and 242 J kg^-1, in males and females, respectively). In male athletes, competitive performance was significantly related to maximum power output and upper limb reaction time only, whereas in females, performance was related to maximum power output and ventilatory threshold level. These variables accounted for 66 and 67% of the performance rank in males and females, respectively. Time-motion analysis of competition taekwon-do fighting (two times 2 min) revealed 3-5 s bouts of maximum exercise alternating with low-intensity periods. This elicits high heart rates (100% HR_max) and lactate responses (11.4 mmol 1^-1 = 81% LA_max), which agrees well with the physiological characteristics of taekwon-do black belts measured in laboratory exercise tests.

In order to describe the kinetics of the reaction of the heart rate (HR) to the onset of exercise of constant intensity, the half‐time (t _1/2) of HR can be used. First in a study of exercise of intensity corresponding to 2 W kg^‐1 on a cycle ergometer, the t _1/2 in 15 trained male rowers and 11 untrained male students was determined. In the trained subjects t _1/2 was smaller than in untrained students, mean (±s.d.) values being 24.10 (±3.36) s and 47.12 (±4.08) s respectively. In both groups t _1/2 was positively correlated with resting HR, r=0.774 and 0.846 and negatively correlated with maximal oxygen uptake (VO₂max), r= ‐0.728 and ‐0.871 respectively (P<0.01). The regulation of HR in the transition range was concluded to be very similar to the regulation of VO₂ and energy requirements. The second part of this work was concerned with responses to graded exercise. The linearity of the HR‐exercise intensity relationship is maintained up to a submaximal exercise intensity beyond which the increase in exercise intensity exceeds the increase in HR. It was hypothesized that the point where HR departs from linearity in an incremental exercise test may be employed as a predictor of the ventilatory threshold (Tvent). To examine this, 28 trained male long‐distance runners were tested on a treadmill and 17 untrained young male subjects were tested on a cycle ergometer using a continuous incremental protocol. The Tvent was determined from the dependence of V _E on VO₂ and/or VCO₂. The VO₂, HR and exercise intensity at Tvent were compared with the same parameters determined from the dependence of HR on exercise intensity. No significant differences were found between Tvent and HR break point levels. It was concluded from this second study that the HR break point level coincides with Tvent.