Feasibility and acceptability of a remotely delivered, home-based, pragmatic resistance 'exercise snacking' intervention in community-dwelling older adults: a pilot randomised controlled trial

Background: Very few older adults meet current muscle strengthening exercise guidelines, and several barriers exist to supervised, community-based resistance exercise programs. Older adults therefore require access to feasible resistance exercise modalities that may be performed remotely. This pilot study assessed the feasibility and acceptability of undertaking a four-week home-based resistance 'exercise snacking' intervention (performed either once, twice, or thrice daily) when delivered and monitored remotely in older adults. Methods: Thirty-eight community-dwelling older adults [mean +/- SD age 69.8 +/- 3.8 y, 63% female] were randomised to complete resistance 'exercise snacks' (9-minute sessions) either once (n = 9), twice (n=10), or thrice (n = 9) daily, or allocated to usual-activity control (n =10). Exercise adherence and adverse events were assessed using an exercise diary, and acceptability of the intervention was explored using an online questionnaire. Physical function [balance, 5-times sit-to-stand (STS), and 30-second STS tests] was assessed remotely at baseline and follow-up using videoconferencing. Results: The intervention was feasible and safe, with 100% participant retention, high adherence (97, 82, and 81% for once, twice, and thrice daily, respectively), and only two adverse events from a total of 1317 'exercise snacking' sessions. The exercise intervention was rated as enjoyable (75% reported their enjoyment as >= 4 on a 5-point Likert scale), easy to perform, and most (82%) planned to continue similar exercise at home. We also found it was feasible to assess measures of physical function via videoconferencing, although effect sizes for 4-week changes in both 5-STS (d range, 0.4-1.4) and 30-STS (d range, 0.7-0.9) following the exercise intervention were similar to controls (d= 1.1 and 1.0 for 5-STS and 30-STS, respectively). Conclusions: Resistance 'exercise snacking' may be a feasible strategy for engaging older adults in home-based resistance exercise when delivered and monitored remotely. The findings of this pilot feasibility trial support the need for longer-term studies in larger cohorts to determine the effectiveness of resistance 'exercise snacking' approaches for improving physical function in older adults.