Aquatic HIIT boosts exercise capacity in adults with chronic conditions

Aquatic high-intensity interval training (AHIIT) may be a safe and valuable alternative for people with chronic conditions who are unable to perform land-based training (LBHIIT), new research suggests.

To investigate the effect of AHIIT, the researchers analysed 18 trials that compared how AHIIT improved participants’ exercise capacity (measured by oxygen consumption, walking tests and physical fitness tests) with LBHIIT, moderate-intensity exercise in water (AMICT) or a non-exercising control group.

Around 868 study participants (74% women) had a range of conditions including back pain, arthritis, chronic lung disease (COPD), type 2 diabetes and multiple sclerosis. Some had more than one chronic condition.

The results show that AHIIT moderately improved participants’ exercise capacity compared with no exercise and had a small beneficial effect compared with AMICT, but no difference in exercise capacity was seen for AHIIT compared with LBHIIT.

There were fewer adverse events reported in AHIIT than with LBHIIT, and adherence rates for AHIIT ranged from 84 to 100%.

“A key finding of this meta-analysis indicates that AHIIT may be as beneficial as LBHIIT, 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,” the researchers said, adding that the natural support and buoyancy of water “may facilitate this effectiveness”.

The researchers acknowledged that some of the trials did not include a blind assessor, which may have affected results, and none of the studies looked at long-term improvements on exercise capacity or quality of life.

However, the detailed search strategy and inclusion of several chronic conditions, adverse events and adherence enabled a greater depth of understanding of AHIIT in a variety of populations.

The researchers suggested 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.

The study has been published in BMJ Open Sport & Exercise Medicine.

Image credit: iStockphoto.com/FG Trade