Table 2.
Surface EMG measurements of the vastus lateralis.
| Young control (n = 15) | Young endurance (n = 8) | Young power (n = 11) | Old control (n = 22) | Old endurance (n = 18) | Old power (n = 11) | P-value for age × discipline interaction | P-value for age difference | P-value for discipline difference | |
|---|---|---|---|---|---|---|---|---|---|
| CMAP (μV.ms) | 98240 (20549) | 92012 (14233) | 98496 (24841) | 65266 (15810) | 74913 (19897) | 70538 (10584) | 0.263 | <0.001 | 0.846 |
| sMUP (μV.ms) | 506 (234) | 537 (201) | 497 (223) | 418 (145) | 499 (178) | 451 (215) | 0.868 | 0.201 | 0.551 |
| MUNE | 233 (113) | 199 (96) | 219 (76) | 168 (60) | 168 (77) | 184 (77) | 0.687 | 0.024 | 0.679 |
| MUs identified (number per person) | 26 (12) | 27 (12) | 28 (11) | 25 (9) | 21 (10) | 24 (11) | 0.475 | 0.894 | 0.061 |
Interaction effects and main effects of age and discipline are shown in final columns. CMAP, compound muscle action potential; sMUP, surface motor unit potential; MUNE, motor unit number estimate. P-values for significant differences are shown in bold.