TABLE 5.
Multiple linear regression analysis: percentage of change in HR measurements with accumulated load, baseline fitness levels, and PHV.
| Variable | β | Estimate | | t| | P-value | 95% CI for estimated | Total predict |
| HRmax (%) | β0 | 110.3 | 1.57 | 0.138 | −40.24 to 260.8 | R2 = 0.50 |
| ACL (A.U.) | β1 | ≤−0.001 | 0.85 | 0.409 | −0.002 to ≤ 0.001 | Adjusted |
| Maturity offset (years) | β2 | −1.46 | 0.49 | 0.634 | −7.88 to 4.96 | R2 = 0.21 |
| PHV (years) | β3 | −5.44 | 1.42 | 0.179 | −13.68 to 2.81 | P = 0.17 |
| VO2max (mL⋅kg–1 ⋅ min–1) | β4 | 0.27 | 0.95 | 0.357 | −0.34 to 0.88 | AIC = 122.93 |
| HRmax (bpm) | β5 | −0.47 | 2.93 | 0.011 | −0.82 to −0.13 | |
| HRrest (bpm) | β6 | 0.36 | 1.97 | 0.069 | −0.03 to 0.75 | |
| LSS (s) | β7 | −3.12 | 0.77 | 0.456 | −11.86 to 5.62 | |
| LSM (s) | β8 | 0.79 | 0.31 | 0.759 | −4.6 to 6.17 | |
| Variable | β | Estimate | | t| | P value | 95% CI for estimated | Total predict |
| HRrest (%) | β0 | 60.38 | 0.74 | 0.468 | −113.1 to 233.9 | R2 = 0.43 Adjusted R2 = 0.01 P = 0.32 AIC = 129.46 |
| ACL (A.U.) | β1 | ≤ 0.001 | 0.93 | 0.368 | ≤−0.001 to 0.003 | |
| Maturity offset (years) | β2 | −4.42 | 1.28 | 0.221 | −11.82 to 3 | |
| PHV (years) | β3 | −6.33 | 1.43 | 0.175 | −15.8 to 3.18 | |
| VO2max (mL⋅kg–1 min–1) | β4 | −0.1 | 0.31 | 0.765 | −0.8 to 0.6 | |
| HRmax (bpm) | β5 | −0.02 | 0.13 | 0.901 | −0.42 to 0.38 | |
| HRrest (bpm) | β6 | −0.13 | 0.62 | 0.546 | −0.58 to 0.32 | |
| LSS (s) | β7 | −5.1 | 1.1 | 0.296 | −15.17 to 4.98 | |
| LSM (s) | β8 | 3.406 | 1.18 | 0.259 | −2.79 to 9.61 | |
Significant differences (p ≤ 0.05) are highlighted in bold font. PHV, peak height velocity; VO2max, maximal oxygen consumption; HRmax, maximal heart rate; HRrest, resting heart rate; LSS, linear sprint short test; LSM, linear sprint medium test; ACL, accumulated load of 20 weeks;%, percentage of change in between assessments from EaS to EnS; CI, confidence interval; AIK, Akaike information criterion; A.U., arbitrary unit.