Loss of functional capacity negatively impacts the quality of life in older adults. This single-site randomized controlled study examined whether short- (one week) and long-term (three months) blackcurrant supplementations combined with habitual physical activity would improve functional capacity and quality of life in previously sedentary older women. Thirty sedentary, healthy older women were randomly assigned to receive blackcurrant supplementation (400 mg of blackcurrant extract) (Polyphenol group, n=15; 74.2±10.0 years) or no supplementation (capsules of 400 mg of corn flour) (Placebo group, n=15; 72.8±8.7 years). Each group consumed two capsules daily for one week and three months, with a washout period of one week between the two phases. The polyphenol group was required to increase habitual activity levels. Participants underwent a functional capacity assessment consisting of a sixminute walk, sit-to-stand test, Berg balance scale measurement and quality of life evaluation with the Scale of Life Satisfaction Index (LSI) at the start, after one week, and after three months of supplementation. Walking distance and time to sit-to-stand improved by 2.5% (p=0.005) and 7.5% (p=0.005), respectively, after one week in the polyphenol group. After 3 months, walking distance in the six-minute walk test increased by 12.3% (p=0.001) while the time to sit-to-stand decreased by 16% (p=0.002) in the polyphenol compared to placebo group, respectively. No differences in Berg balance scale were observed. Quality of life, indexed by LSI, improved by 39% (p=0.001) in the polyphenol compared to the placebo group. Blackcurrant supplementation, combined with habitual activity, may enhance functional capacity and quality of life in older women, offering a potential strategy to maintain independence. However, future studies should address longer durations to validate these findings.