I am a traucer [frerunning/ parkour practitioner] and while bruises are common and training rules mean that serious injuries rarely happen, stresses on the body are dealt with exercise and stretching; But in and of itself, is a temporary high pulse dangerous in the long run? I have measured my pulse after a normal 3 minutes intense practise session and it usually is around 210-230. The highest ever was around 255. It normalises in less than 7-10 minutes. Should I worry? OMG! I miscalculated! Its around 190-210 and highest was 230s. Also normalisation was around 6 minutes. I did the calculations again with 10 second and 10x methos.