Heart rate and rating of perceived exertion in simulated competitive fights in brazilian karate fighters.

Background: The knowledge of the physiological responses of karate fighting can help coaches and trainers in planning training. Research question: The purpose of this study was to determine the intensity of karate fighting by monitoring heart rate (HR) and the rating of perceived exertion (RPE), and to analyse the relationship between these variables in a protocol simulating a competitive situation of consecutive fights. Type of study: Cross-sectional study. Methods: Nine karate athletes underwent a protocol of four consecutive karate fights of one minute each, separated by five minutes of rest. Throughout the protocol there was continuous HR monitoring, and the RPE was assessed at the end of each fight. Results: Values for HRmean, HRpeak and RPE were 162.0 (± 11) bpm, 182.5 (± 9.6) bpm and 4.0 (± 1.9), respectively. The HR values during fights corresponded to an intensity of 83.5% (± 5.3) and 94.0% (± 3.9) of the maximum heart rate determined in a laboratory exercise test. In addition, there were significant and positive correlations between the HRmean and the RPE (r = 0.59) and between HRpeak and the RPE (r = 0.67). Conclusion: It was concluded that karate is a high-intensity sport and the use of CR-10 Borg scale may be a suitable method for the control of karate fight workloads in situations lacking objective methods.