Abstract
The aim of this study was to investigate the effects of PAP induced by different squat amplitudes on squat jump and the interaction between squat amplitude, stimulus load (%1RM) and PAP duration, and to establish an exercise intervention programme.
Method: Fifteen track and field athletes aged 20-22 years were selected to perform barbell back squats at knee angles of 60°, 90° and 120° and loads of 75% 1RM, 85% 1RM and 95% 1RM, and their flat squat heights were tested at the 3rd, 6th, 9th and 12th minute after each combination of barbell back squats.
Results: (1) The 120° knee angle-95%1RM combination produced the best squat jump performance after stimulation (42.47±5.26cm), combinations close to this result include the 120° knee angle-85%1RM (42.27±4.70cm) and the 90° knee angle-95%1RM (42.40±5. 50cm); (2) when load and interval were the same, the effect of different knee angles on squat performance was 120 knee angle > 90 knee angle > 60 knee angle, and when knee angle and interval were the same, the effect of different loads of 1RM on squat performance was 95%1RM>85%1RM>75%1RM, with a high probability of peak occurring at the 9th minute after stimulation.
Conclusion: Athletes participating in lower limb explosive power events such as the high jump and long jump should perform a PAP induction with a back squat at a knee angle of 90°-120° and 85-95% of 1RM weight 6-12 minutes prior to competition.