WB-EMS Combined With Nutritional Guidance for a High-Protein Diet on Body Composition, Muscle Function, Psychological and Functional Outcomes in Older Adults With Excess Adiposity

Kurzzusammenfassung

This is a 16-week randomized controlled trial (RCT) with outcome assessor blinding. The objective is to investigate the effects of resistance training (RT) combined with whole-body neuromuscular electrical stimulation (WB-NMES) and a high-protein diet on body composition, anthropometry, and quality of life. Sample and Group Allocation The sample will comprise 36 older adults (≥ 60 years), physically inactive, and with overweight or obesity (BMI ≥ 25 kg/m²). They will be randomized (stratified by sex) into four groups of 9 participants: RT + NOR: Resistance training + normal-protein diet. RT + PRO: Resistance training + high-protein diet. WB-NMES + RT + NOR: Resistance training with electrical stimulation + normal-protein diet. WB-NMES + RT + PRO: Resistance training with electrical stimulation + high-protein diet. Intervention Protocol Exercise (2x/week, 25 min/session): Seven exercises (2 sets of 1 min execution with 45s of rest). Progressive intensity controlled by the OMNI-RPE Scale. Electrical Stimulation (WB-NMES Groups): Simultaneous use of an electrode suit (85 Hz, 400 µs pulse width, 5s on/5s off duty cycle), with intensity capped at a maximum of 5/10 on the pain/discomfort Visual Analog Scale (VAS). Nutrition (In-person + Remote): High-protein (PRO) groups will focus on an intake of 1.2 to 1.5 g of protein/kg/day. Normal-protein (NOR) groups will receive general healthy eating guidelines, without encouraging an increase in protein intake. Assessments and Outcomes (Conducted at T0 and T16) Body Composition and Anthropometry: Multi-frequency bioelectrical impedance (InBody 570) and circumference measurements following ISAK guidelines. Physical and Functional Performance: Handgrip strength (dynamometry). Muscular endurance (30-second chair stand and arm curl tests). Upper limb power (2 kg medicine ball throw). Aerobic endurance (6-Minute Walk Test). Mobility and fall risk (Timed Up and Go - TUG). Questionnaires and Scales: Self-reported functional disability (WHODAS 2.0). Basic psychological needs satisfaction (BPNES). Motivational regulation in exercise (BREQ-3). Quality of life specific for older adults (WHOQOL-OLD). Adherence: Minimum attendance goal of 75% for the sessions. Statistical Analysis The analysis will follow the intention-to-treat (ITT) principle. Data will be analyzed using Linear Mixed Models for Repeated Measures (fixed factors: Group and Time), followed by Tukey's post-hoc test, adopting a significance level of $p \< 0.05$.