Table 3 Pearson correlation coefficient between peak vertical forces (F1 and F2) and the temporal factors: time F1 and F2 appear (T1 and T2), time between peaks (TP) and length of the impact absorption phase (T) (n = 30). F1 F2 TP T1 T2 T F1 Pearson Correlation 1 -.027 .412(*) .181 .418(*) -.124 Sig. (2-tailed) .886 .024 .338 .022 .513 F2 Pearson Correlation -.027 1 -.417(*) -.136 -.406(*) -.100 Sig. (2-tailed) .886 .022 .474 .026 .598 TP Pearson Correlation .412(*) -.417(*) 1 .225 .939(**) -.383(*) Sig. (2-tailed) .024 .022 .233 .000 .037 T1 Pearson Correlation .181 -.136 .225 1 .545(**) -.321 Sig. (2-tailed) .338 .474 .233 .002 .084 T2 Pearson Correlation .418(*) -.406(*) .939(**) .545(**) 1 -.443(*) Sig. (2-tailed) .022 .026 .000 .002 .014 T Pearson Correlation -.124 -.100 -.383(*) -.321 -.443(*) 1 Sig. (2-tailed) .513 .598 .037 .084 .014 * Correlation is significant at the 0.05 level (2-tailed). ** Correlation is significant at the 0.01 level (2-tailed).