Table 1.
Quadriceps muscle size indices, individual constituent muscle volumes and proportional volumes of untrained (UT) and long-term resistance-trained (LTT) men
| Muscle and Size Variable | UT (n = 52) | LTT (n = 16) | %Difference | Effect Size |
|---|---|---|---|---|
| Quadriceps | ||||
| QVOL (cm3) | 1,838.2 ± 262.9 | 2,881.9 ± 308.1* | 56 | 3.7 |
| QACSAMAX (cm2) | 86.2 ± 11.2 | 135.0 ± 15.0* | 50 | 3.3 |
| QPCSA (cm2) | 174.4 ± 19.8 | 245.7 ± 16.8* | 41 | 3.9 |
| QEFFPCSA (cm2) | 167.7 ± 18.8 | 236.8 ± 15.1* | 41 | 4.1 |
| Individual muscle volume (cm3) | ||||
| VM | 441.4 ± 67.8 | 691.2 ± 87.0* | 57 | 3.2 |
| VI | 546.9 ± 104 | 846.4 ± 124.0* | 55 | 2.6 |
| VL | 609.8 ± 98.4 | 964.3 ± 90.6* | 58 | 3.8 |
| RF | 240.2 ± 46.7 | 374.6 ± 72.0* | 56 | 2.3 |
| Proportional muscle volume (%QVOL) | ||||
| VM | 24.0 ± 1.7 | 24.1 ± 1.9 | 0 | 0.0 |
| VI | 29.7 ± 2.8 | 29.3 ± 1.6 | 1 | −0.2 |
| VL | 33.2 ± 2.6 | 33.6 ± 2.3 | 1 | 0.2 |
| RF | 13.1 ± 1.8 | 13.0 ± 1.8 | 1 | −0.1 |
Data are means ± SD, QVOL = quadriceps volume; QACSAMAX = sum of maximal anatomical cross-sectional areas from individual muscles; QPCSA = quadriceps physiological cross-sectional area; QEFFPCSA = effective physiological cross-sectional area; VM = vastus medialis; VI = vastus intermedius; VL = vastus lateralis; RF = rectus femoris;
*
indicates adjusted P < 0.01