To examine the effects of 12 weeks group-based peer-led aquatic high-intensity interval training (AHIIT) compared with aquatic moderate continuous training (AMICT) on patient-reported outcome measures (PROMs) and quality-adjusted life-years (QALYs).

A single-blind, parallel-group, randomised trial with a 1:1 allocation ratio.

Community-based setting.

89 participants (mean age 62 (SD 13) years) with rheumatic and musculoskeletal diseases, including hip and knee osteoarthritis, fibromyalgia, rheumatoid arthritis, psoriatic arthritis and axial spondyloarthritis, were randomly allocated to an AHIIT (n=44) or an AMICT (n=45) group.

The intervention consisted of AHIIT (four intervals of 4 min at high intensity, Borg scale 14–18) or AMICT (Borg scale 12–13), conducted twice weekly for 12 weeks.

Outcomes included disease activity (measured by the Patient Global Assessment), fatigue, pain and health-related quality of life (HRQoL), measured by the EQ-5D utility index (five-dimensional health status measure) and EQ VAS (self-rated overall health scale) for overall health, physical and social activities. All outcomes were assessed at baseline, 3 months and 6 months. To compare the overall benefit of these interventions, QALYs were estimated based on HRQoL. Linear mixed models for repeated measures were used to estimate the mean difference (95% CI) in outcomes.

No statistically significant differences between the groups were found in any outcomes at either three or 6 months (p>0.05).

No difference between the groups was found on PROMs and QALYs. Future research should include larger sample sizes and a non-exercising control group to better determine the efficacy of AHIIT and clarify the role of exercise intensity in symptom management.

NCT05209802.