Table 2.
Effects of the intervention on muscle quantity and stiffness in the PPS analysis.
| Variable | Group | Baseline | 12 weeks | 24 weeks | Change (Δ 12 weeks) | Change (Δ 24 weeks) | Two-way ANOVA (group × time) P-value |
|---|---|---|---|---|---|---|---|
| MRI measurements | |||||||
| Thigh muscle CSA (cm2) | Placebo | 98.7 ± 17.4 | 102.0 ± 18.5 | 104.2 ± 19.2 | 3.3 ± 2.6 | 5.5 ± 3.6 | 0.915 |
| Low-QG | 102.7 ± 25.4 | 106.2 ± 25.8 | 109.0 ± 28.2 | 3.4 ± 2.4 | 6.3 ± 4.4 | ||
| High-QG | 101.0 ± 25.3 | 105.1 ± 26.9 | 107.3 ± 27.4 | 4.1 ± 2.6 | 6.3 ± 4.5 | ||
| VL muscle CSA (cm2) | Placebo | 17.0 ± 3.6 | 17.6 ± 3.8 | 17.8 ± 3.9 | 0.6 ± 0.7 | 0.9 ± 0.9 | 0.635 |
| Low-QG | 18.3 ± 4.1 | 18.9 ± 4.2 | 19.5 ± 5.0 | 0.6 ± 0.8 | 1.2 ± 1.3 | ||
| High-QG | 17.7 ± 4.6 | 18.1 ± 4.6 | 18.5 ± 4.9 | 0.5 ± 0.7 | 0.8 ± 0.9 | ||
| DXA measurements | |||||||
| Leg lean mass (kg) | Placebo | 13.2 ± 2.3 | 13.5 ± 2.5 | 13.6 ± 2.7 | 0.3 ± 0.4 | 0.3 ± 0.6 | 0.332 |
| Low-QG | 13.7 ± 3.8 | 14.1 ± 3.9 | 13.9 ± 3.9 | 0.5 ± 0.4 | 0.2 ± 0.4 | ||
| High-QG | 13.1 ± 3.4 | 13.3 ± 3.6 | 13.4 ± 3.5 | 0.2 ± 0.5 | 0.3 ± 0.3 | ||
| Arm lean mass (kg) | Placebo | 4.1 ± 1.1 | 4.2 ± 1.1 | 4.2 ± 1.1 | 0.1 ± 0.1 | 0.0 ± 0.1 | 0.489 |
| Low-QG | 4.2 ± 1.4 | 4.2 ± 1.4 | 4.2 ± 1.4 | 0.0 ± 0.1 | 0.0 ± 0.2 | ||
| High-QG | 4.1 ± 1.3 | 4.1 ± 1.3 | 4.1 ± 1.2 | 0.1 ± 0.2 | 0.0 ± 0.1 | ||
| Whole-body lean mass (kg) | Placebo | 40.0 ± 6.9 | 40.7 ± 6.9 | 40.8 ± 7.3 | 0.6 ± 0.6 | 0.8 ± 0.9 | 0.904 |
| Low-QG | 40.6 ± 9.9 | 41.4 ± 10.1 | 41.4 ± 10.3 | 0.7 ± 0.7 | 0.8 ± 1.0 | ||
| High-QG | 39.8 ± 9.4 | 40.3 ± 9.4 | 40.6 ± 9.1 | 0.5 ± 0.6 | 0.8 ± 1.0 | ||
| SWE measurements of VL | |||||||
| SWV with the knee fully extended (m/s) | Placebo | 2.0 ± 0.1 | 2.0 ± 0.1 | 2.0 ± 0.1 | 0.0 ± 0.1 | 0.0 ± 0.1 | 0.452 |
| Low-QG | 1.9 ± 0.1 | 1.9 ± 0.2 | 1.9 ± 0.1 | 0.0 ± 0.2 | 0.0 ± 0.1 | ||
| High-QG | 2.0 ± 0.1 | 1.9 ± 0.2 | 2.0 ± 0.1 | 0.0 ± 0.1 | 0.0 ± 0.1 | ||
| SWV with the knee flexed at 90° (m/s) | Placebo | 3.0 ± 0.2 | 2.9 ± 0.2 | 2.8 ± 0.2 | −0.1 ± 0.2 | −0.2 ± 0.2 | 0.811 |
| Low-QG | 2.9 ± 0.2 | 2.8 ± 0.3 | 2.7 ± 0.1 | −0.1 ± 0.2 | −0.1 ± 0.2 | ||
| High-QG | 2.9 ± 0.3 | 2.8 ± 0.3 | 2.8 ± 0.2 | −0.2 ± 0.2 | −0.2 ± 0.2 | ||
| SWV with the knee fully flexed (m/s) | Placebo | 4.7 ± 0.6 | 4.6 ± 0.5 | 4.4 ± 0.4§§ | −0.1 ± 0.3 | −0.3 ± 0.4 | 0.023 |
| Low-QG | 5.0 ± 0.5 | 4.7 ± 0.6§§ | 4.4 ± 0.4§§ | −0.4 ± 0.3 | −0.6 ± 0.3* | ||
| High-QG | 5.0 ± 0.8 | 4.8 ± 0.8 | 4.4 ± 0.5§§ | −0.2 ± 0.5 | −0.6 ± 0.5* |
Values are expressed as means ± standard deviation. For the placebo (n = 16), low-QG (n = 16), and high-QG (n = 16) groups on MRI, DXA, and SWE measurements, where one set of SWE measurements in the placebo group at 12 weeks was missing because of no visit, there were no significant differences among the groups at baseline (one-way ANOVA). *p < 0.05 compared with placebo group (Dunnett's test). §§p < 0.01 compared with values at baseline (Dunnett's test). QG, quercetin glycoside; MRI, magnetic resonance imaging; CSA, cross-sectional area; VL, vastus lateralis; DXA, dual energy X-ray absorptiometry; SWE, shear wave elastography; and SWV, shear wave velocity.