Fig. 2

Effects of exercise interventions on morphological muscle quality in 562 participants, 13 studies, 15 intervention arms, and 54 outcomes (g = 0.21, 95% CI 0.03–0.40, p = 0.029, median I² = 34%). Positive effect sizes denote favorable effects of exercise on morphological muscle quality. Abbreviations: AT, aerobic training; BT, balance training; CT, computed tomography; EI, echo intensity; FA, fat area; FA, fat density; HD, high density; IM, intramuscular; LD, low density; M/F, muscle to fat ratio; MD, muscle density; MRI, magnetic resonance imaging; MT, multimodal training; OT, other exercise training; pQCT, peripheral quantitative computed tomography; RT, resistance training; SC, subcutaneous; US, ultrasound imaging