The use of blood-flow restriction (BFR) cuffs that "hack" your physiology to speed up strength and muscle gains when you do light workouts has been growing in popularity in recent years. However, researchers have now discovered that they come with a significant downside – especially the older you get.
Researchers from Murdoch University’s School of Allied Health and Health Futures Institute in Australia investigated whether these cuffs, which first gained attention through use by athletes for training and recovery, had any less desirable outcomes – particularly with older, active people.
They recruited 10 healthy adults with an average age of 73 years and had them walk on a treadmill for 10 minutes at different speeds, without wearing a BFR cuff. Then they were fitted with the cuffs and repeated the exercise with the bands at 40% inflation and then 60% inflation – the higher the percentage, the more restriction the cuff applies, with 100% completely stopping all blood flow.
A small motion sensor attached to the participants' lower backs gathered data on balance as they walked on the treadmill at various speeds and with the differing cuff settings. What they found was that the inflated cuffs tool took a direct toll on balance – which is, of course, a major contributor to potentially serious falls as we get older.
"Walking balance worsened with BFR, independent of walking speed, for all outcomes except the magnitude of the dominant period of forwards accelerations, with worse balance observed with increasing cuff pressure," the team noted. "Compared to no BFR, gait quality declined 12 % when walking with 50 % occlusion and declined 20 % with 60 % occlusion."
“Blood flow restriction training can be a powerful tool for improving strength and functional abilities in older adults, but our research shows that wearing these cuffs while walking changes how older adults walk, so exercise needs to be done in a safe environment,” said Associate Professor Brendan Scott from the Centre for Healthy Ageing at Murdoch University.
The cuffs work much like they sound – they restrict some blood being pumped in and out of the legs (or arms), creating a low-oxygen environment to put greater strain on muscles even when the workload is otherwise fairly light. But while walking with BFR cuffs can increase the size and strength of leg muscles – also vital for healthy aging and staying active – the researchers want people to be aware that extra precautions and care are necessary, as restricting blood flow can have an immediate negative effect.
“We found that regardless of how fast people walked, wearing inflated BFR cuffs worsened their balance, and the more we inflated the cuffs, the worse their balance became," said Associate Professor Brook Galna.
But it's not all bad news. The bands may actually help improve balance in the long term – which is linked to muscle strength and growth, too – but use of BFR cuffs can hamper natural movement in the moment and therefore older adults should remain aware of their higher fall risk as a result.
“Blood-flow restriction training can deliver real benefits, and it’s possible that by challenging balance with BFR walking in a safe environment, older adults may adapt to actually enhance their balance,” Scott added. “We’ve overseen hundreds of BFR walking sessions and have not had any trips or falls caused by the cuffs.
“It is important that if you’re considering BFR, do it under professional supervision and start with low pressures in a safe environment," he added.
The research was published in the journal Gait & Posture.
Source: Murdoch University
