OBJECTIVES: To evaluate the effects of elastic band resistance training in combination with nutrient supplementation on muscular strength and the ability to perform mobility-related activities of daily living in older adults living in retirement care facilities. DESIGN: Randomized controlled trial, with a 6-month intervention period. SETTING: A retirement care facility, Vienna, Austria. PARTICIPANTS: One hundred and seventeen older adults (14 males (12%) and 103 females (88%)), aged 65 to 97 years (mean age: 82.8 ± 6.0), having a mini-mental state examination score ≥ 23 and no chronic diseases posing a medical contraindication to training therapy. INTERVENTION: Participants were randomly assigned, but stratified by sex, to one of three intervention groups: supervised resistance exercise training (RT), RT in combination with nutrient supplementation (RTS), or cognitive training group (CT). All interventions were performed two times a week for 6 months. RT was designed to train all major muscle groups using elastic bands. The nutrient supplement (rich in proteins, vitamin D, B2, B12) was distributed every morning as well as after each RT session. MEASUREMENTS: A battery of motor ability tests and functional test were performed prior to as well as following 3 months and finally after 6 months of intervention. These tests included isokinetic torque measurements of the knee extensors and flexors in concentric mode at 60 and 120°/s, isometric handgrip strength, senior arm-lifting test, chair stand test, maximum walking speed and a 6-minute walking test (6 MWT). RESULTS: A repeated-measures ANOVA analysis revealed significant improvements in physical function of lower (p=0.002) and upper extremities (p=0.006) for RT and/or RTS in comparison to CT. For isokinetic measurements, 6 MWT, and gait speed time effects (p<0.05) were detected without any group × time interaction effects. Dropouts showed lower performance in chair stand test (p=0.012), 6 MWT (p=0.003), and gait speed (p=0.013) at baseline than that of the finishers of the study. CONCLUSION: Six months of a low intensity resistance exercise using elastic bands and own body weight is safe and beneficial in improving functional performance of institutionalised older people. Multinutrient supplementation did not offer additional benefits to the effects of RT in improving muscular performance.