Purpose To compare the effects of two resistance training (RT) frequencies (two vs. three sessions per week) on phase angle (PhA), a bioimpedance-derived marker, and muscle quality index (MQI) in older women under matched weekly training volume.Methods Forty-five older women (G2x: n = 22; G3x: n = 23; 63.2 ± 4.5 years) completed 12 weeks of supervised RT. Outcomes included fat mass, FFM, resting metabolic rate, total body water, PhA, and MQI, calculated as one-repetition maximum (1RM) divided by the corresponding segment-specific fat-free mass (FFM) measured by DXA for the chest press, leg extension, and preacher curl exercises. This study represents a secondary analysis of data from a previously published trial, focusing on neuromuscular efficiency and PhA.Results MQI increased significantly over time in both groups (p < 0.001), with no time × group interactions observed across exercises. No group-level changes were detected for PhA, and mean fluctuations remained below the minimal detectable change. Fat mass decreased modestly in the 3×/week group, whereas FFM increased slightly in both groups.Conclusion When weekly training volume was equated, RT performed two or three times per week resulted in similar improvements in MQI, with no group-level changes observed for PhA in older women.
Nascimento et al. (Tue,) studied this question.