Heart rate variability of squat jump activity on land-, sand- and aquatic-based surfaces

The purpose of this study is to examine the variability of heart rate in squat jump activity performed on three different surfaces and environment: land-, sand-, and aquatic-based. Three male subjects aged 20-23 years (mean ± SD, ages: 21.67 ± 1.53 yr, weight: 71.00 ± 11.36 kg, height: 168.33 ± 7.64, BMI: 24.93 ± 2.32) voluntarily participated in the study and completed three days of plyometric squat jump testing. Nonparametric K-related sample (Friedman's test) was used to measure the difference between performances for plyometric exercises on three different surfaces. Statistical analysis proved no significant differences (p > .01) for average and maximum heart rate for the three different surfaces (p = 0.717 and p = 0.097, respectively). The subjects agreed that the aquatic-based plyometric testing had reduced their muscle soreness during the testing