Aquatic High Intensity Interval Training works for people with chronic health conditions

Sophie Heywood

We are so pleased to be connected to this piece of research and congratulate the main researcher Heidi Bunaes-Naess and the team from Norway on this recent study in Aquatic High Intensity Interval Training (AHIIT).

The HIIT in water improves exercise capacity in adults with long term health conditions. AHIIT offers alternative exercise option for people unable to perform land based HIIT movements. High-intensity interval training in water, often called aquatic HIIT (AHIIT) improves exercise capacity in adults with chronic conditions and has a similar impact as land-based training (LBHIIT), suggests research published in the journal BMJ Open Sport & Exercise Medicine. The research team that we were connected to found that AHIIT may provide a safe and valuable alternative for people with chronic conditions who are unable to perform land exercise at high intensity.

HIIT is a type of interval training exercise that involves brief bursts of high intensity movements followed by short recovery periods of lower intensity movements. HIIT is considered to have more health benefits than moderate-intensity exercise for people with and without chronic conditions. It increases aerobic capacity and endurance while being time efficient, making it an attractive exercise option. Exercising in water can also help to relieve pressure on joints, allowing people to complete movements they cannot do on land.

To investigate the effect of AHIIT, the research team we were connected to analysed 18 trials that compared how AHIIT improved participants’ exercise capacity (measured by oxygen consumption, walking tests and physical fitness tests) with land-based HIIT. Some 868 participants (74% women) were included who had a range of conditions including back pain, arthritis, chronic lung disease (COPD), type 2 diabetes, and multiple sclerosis. Some participants had more than one chronic condition. Differences between groups were expressed as standardised mean differences(SMD). Generally, an SMD of 0.2-0.5 indicates a small effect, 0.5-0.8 a moderate effect, and 0.8 or more a large effect. The results show that AHIIT moderately improved participants’ exercise capacity compared with no exercise (SMD 0.78), and a similar beneficial effect for improving exercise capacity was seen for AHIIT compared with land-based HIIT.

There were fewer adverse events reported in AHIIT than with LBHIIT, and adherence rates for AHIIT ranged from 84% to 100%. The research team goes on to conclude “A key finding of this meta-analysis indicates that AHIIT may be as beneficial as land-based HIIT, which gives people with chronic conditions another choice for effective HIIT or potentially a more successful environment to start and continue with high-intensity training,”, adding that the natural support and buoyancy of water“ may facilitate this effectiveness.” And they suggest that future research should examine the link between exercise capacity and key patient-related outcomes, barriers to HIIT and the ongoing independent commitment to exercise.

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