Many older adults do not achieve recommended amounts of aerobic or strengthening exercise and high-intensity interval or circuit-based strengthening may offer a time-efficient solution. This review sought to determine the effects of high-intensity interval/circuit strengthening on physical and cognitive functioning for community-dwelling older adults, and its associated adherence, retention, and adverse events. Six databases were searched to June 2022 and 15 studies (11 for effectiveness) were included. The current certainty of evidence is low to very low; upper body-focused physical functioning measures demonstrated small to large benefits and lower body-focused, self-report, and cardiovascular measures had mixed results. There was insufficient evidence (one study) to determine cognitive effects. The mean adherence rates ranged from 73.5% to 95.8%, overall retention across all studies (n = 812) was 86%, and no serious adverse events were reported, suggesting that this type of exercise is feasible for community-dwelling older adults.
Keywords: effectiveness; exercise; feasibility; resistance training.