Table 3.
Handgrip force, isometric force, countermovement jump height, and respiratory exchange data while running at 10 km/m, in ACTN3 RR, RX, and XX marathon runners. Data are mean ± SD for each group. ES = Effect size calculated with Hedges’ g; CI = Confidence interval; VO2 = oxygen uptake. Degrees of freedom = 2, between-groups; 133, intra-group; 135, total.
| Variable (Units) | RR | RX | XX | ES ± 95% CIRR vs. RX |
ES ± 95% CIRR vs. XX |
ES ± 95% CIRX vs. XX |
p | η2 |
|---|---|---|---|---|---|---|---|---|
| Non-dominant handgrip force (N) | 388 ± 73 | 402 ± 79 | 393 ± 91 | 0.3 ± 0.3 | 0.1 ± 0.4 | −0.1 ± 0.4 | 0.663 | <0.01 |
| Dominant handgrip force (N) | 414 ± 67 | 421 ± 81 | 415 ± 89 | 0.1 ± 0.4 | 0.0 ± 0.4 | −0.1 ± 0.4 | 0.897 | <0.01 |
| Isometric force (N/kg) | 16.7 ± 4.7 | 15.6 ± 4.4 | 14.7 ± 4.0 | −0.2 ± 0.3 | −0.5 ± 0.3 | −0.2 ± 0.3 | 0.038 | 0.03 |
| Countermovement jump height (cm) | 26.9 ± 4.2 | 26.8 ± 5.3 | 26.2 ± 5.4 | 0.0 ± 0.4 | −0.1 ± 0.3 | −0.1 ± 0.4 | 0.818 | <0.01 |
| Tidal volume (L/respiration) | 2.3 ± 0.7 | 2.5 ± 0.6 | 2.3 ± 0.6 | −0.2 ± 0.3 | 0.0 ± 0.4 | −0.2 ± 0.3 | 0.388 | 0.01 |
| Respiratory rate (respirations/min) | 28.7 ± 7.7 | 28.6 ± 8.7 | 31.8 ± 8.9 | 0.0 ± 0.3 | 0.4 ± 0.4 | 0.4 ± 0.3 | 0.188 | 0.03 |
| Ventilation (L/min) | 62.0 ± 9.5 | 65.8 ± 13.1 | 68.3 ± 12.9 | 0.3 ± 0.4 | 0.6 ± 0.3 | 0.2 ± 0.3 | 0.012 | 0.09 |
| VO2 (mL/kg/min) | 38.4 ± 3.3 | 39.0 ± 3.9 | 39.3 ± 4.1 | 0.2 ± 0.4 | 0.2 ± 0.4 | 0.1 ± 0.4 | 0.389 | <0.01 |
| Respiratory exchange ratio | 0.89 ± 0.06 | 0.89 ± 0.07 | 0.91 ± 0.06 | 0.0 ± 0.3 | 0.3 ± 0.4 | 0.3 ± 0.3 | 0.130 | 0.02 |
| Energy cost of running (J/kg/m) | 4.7 ± 0.4 | 4.8 ± 0.5 | 4.9 ± 0.5 | 0.2 ± 0.4 | 0.4 ± 0.4 | 0.2 ± 0.4 | 0.448 | 0.01 |