Table 1 Changes in body composition and muscle morphology over the course of the fall and spring rugby seasons
Fall Season | Spring Season | Group x Time | ||||
|---|---|---|---|---|---|---|
PRE | POST | PRE | POST | F | p-value | |
Body composition | ||||||
Height (cm) | ||||||
HMB-Cr | 177 ± 7 (172 to 181) | 176 ± 8 (172 to 181) | 179 ± 5 (174 to 184) | 178 ± 5 (175 to 185) | 0.55 | 0.651 |
Cr | 179 ± 6 (175 to 184) | 179 ± 5 (174 to 184) | 179 ± 8 (173 to 183) | 182 ± 4 (173 to 183) | ||
d | 0.37 | 0.46 | 0.01 | 0.85 | ||
Body mass (kg) | ||||||
HMB-Cr | 88.4 ± 15.3 (78.1 to 98.7) | 88.2 ± 16.3 (78.3 to 98.5) | 93.5 ± 14.7 (79.1 to 99.3) | 95.4 ± 16.9 (79.6 to 99.2) | 0.03 | 0.992 |
Cr | 88.3 ± 14.1 (78.0 to 98.6) | 89.0 ± 14.5 (78.4 to 98.5) | 90.6 ± 16.9 (77.9 to 98.0) | 97.6 ± 11.1 (78.9 to 98.3) | ||
d | 0.01 | 0.05 | 0.19 | 0.17 | ||
Body fat percentage (%) | ||||||
HMB-Cr | 15.1 ± 6.5 (10.4 to 19.7) | 13.3 ± 6.3 (8.6 to 17.2) | 18.9 ± 7.5 (7.1 to 20.4) | 21.6 ± 6.0 (9.2 to 21.4) | 0.47 | 0.709 |
Cr | 14.8 ± 6.8 (10.1 to 19.4) | 13.0 ± 6.7 (7.4 to 16.1) | 14.8 ± 11.0 (7.0 to 19.9) | 18.9 ± 7.9 (7.5 to 19.2) | ||
d | 0.05 | 0.05 | 0.44 | 0.40 | ||
Fat-free mass (kg) | ||||||
HMB-Cr | 74.5 ± 10.1 (68.1 to 80.9) | 75.9 ± 10.6 (69.7 to 83.2) | 75.1 ± 6.5 (68.0 to 82.0) | 74.2 ± 8.3 (67.8 to 81.8) | 0.40 | 0.755 |
Cr | 74.7 ± 8.1 (68.3 to 81.1) | 76.8 ± 7.7 (70.9 to 84.5) | 76.1 ± 11.0 (68.2 to 81.6) | 78.5 ± 4.3 (70.2 to 83.4) | ||
d | 0.02 | 0.10 | 0.11 | 0.70 | ||
Muscle thickness (cm) | ||||||
Rectus femoris | ||||||
HMB-Cr | 2.73 ± 0.50 (2.40 to 3.06) | 2.68 ± 0.47 (2.36 to 3.02) | 2.90 ± 0.12 (2.63 to 3.15) | 15.78 ± 3.56 (2.52 to 3.42) | 0.60 | 0.629 |
Cr | 2.92 ± 0.36 (2.59 to 3.25) | 2.75 ± 0.35 (2.44 to 3.15) | 2.84 ± 0.37 (2.60 to 3.03) | 8.90 ± 6.69 (2.67 to 3.45) | ||
d | 0.44 | 0.15 | 0.21 | 1.09 | ||
Vastus lateralis | ||||||
HMB-Cr | 1.89 ± 0.33 (1.64 to 2.14) | 2.11 ± 0.28 (1.80 to 2.36) | 2.32 ± 0.28 (1.92 to 2.46) | 2.06 ± 0.18 (1.81 to 2.27) | 1.77 | 0.194 |
Cr | 2.03 ± 0.44 (1.78 to 2.28) | 2.11 ± 0.52 (1.80 to 2.38) | 1.81 ± 0.21 (1.55 to 2.03) | 1.82 ± 0.14 (1.63 to 2.03) | ||
d | 0.38 | < 0.01 | 1.48 | 1.24 | ||
Pennation angle (°) | ||||||
Rectus femoris | ||||||
HMB-Cr | 16.2 ± 2.7 (13.7 to 18.8) | 15.7 ± 4.9 (12.7 to 18.8) | 14.6 ± 3.8 (11.7 to 17.3) | 20.2 ± 5.3 (15.2 to 25.5) | 0.90 | 0.469 |
Cr | 15.5 ± 4.3 (12.9 to 18.0) | 15.7 ± 2.6 (12.4 to 19.0) | 14.3 ± 2.0 (12.0 to 16.6) | 14.8 ± 4.1 (10.5 to 19.4) | ||
d | 0.22 | < 0.01 | 0.11 | 1.06 | ||
Vastus lateralis | ||||||
HMB-Cr | 12.8 ± 2.2 (11.6 to 14.1) | 12.8 ± 2.1 (11.2 to 14.6) | 16.3 ± 2.2 (14.2 to 18.6) | 14.4 ± 3.1 (11.7 to 17.0) | 5.75 | 0.008 |
Cr | 14.5 ± 1.4 (13.2 to 15.8) | 13.2 ± 2.4 (11.4 to 15.0) | 12.0 ± 2.2 (10.2 to 13.7)# | 13.0 ± 1.6 (10.6 to 15.3) | ||
d | 0.85 | 0.15 | 1.43 | 0.62 | ||