Study explains why walking slows and tires with age

Reasons why our walking becomes slower and more tiring with age have been uncovered by new Australian research - with findings showing the body increasingly sacrifices efficiency to stay upright.

The study, led by Flinders University and the University of Canberra, reveals that as we age, the body adopts a "safety-first" walking style that prioritises stability at the cost of speed and energy efficiency, which helps explain why older adults tire more easily and face a higher risk of falls.

Analyzing movement data from 107 healthy adults aged 26 to 86, researchers identified subtle but important changes in how the ankle and surrounding muscles control each step.

Lead author and expert in sport and exercise technology, Dr. Cody Lindsay, says the ankle plays a critical role in both balance and forward motion.

As we get older, the body starts to favour stability over efficiency. That helps keep us upright, but it also makes walking more of an effort."

Dr. Cody Lindsay, Flinders Caring Futures Institute

The study found older adults increasingly activate opposing muscles around the ankle at the same time - a pattern known as co-contraction - which stiffens the joint and improves balance when the foot hits the ground.

However, Dr. Lindsay says this comes at a cost.

"Stiffening the joint makes walking safer, but it also means the muscles are working harder without generating as much forward movement," he says.

The research also showed older adults produce less push-off power with each step, resulting in shorter strides and slower walking speeds.

Co-author Associate Professor Maarten Immink says this reflects a broader shift in how the body controls movement.

"The nervous system adopts a safety-first approach, compensating for age-related changes by favouring stability over performance," says Associate Professor Immink, Lead of the Active Lives Research Program within the Caring Futures Institute at Flinders University.

"These changes can also increase fatigue and make walking longer distances more challenging, while reducing the ability to recover from trips or slips - a key factor in falls among older adults."

"Even gradual changes can affect confidence and independence, and people may notice they tire more quickly or feel less steady, especially on uneven ground."

Importantly, the findings point to new approaches for maintaining mobility with age.

Rather than focus solely on strength, researchers say exercise programs should also target balance, coordination and identify how muscles work together through each step.

"For older Australians, simple actions can make a difference, including regular physical activity, balance exercises such as tai chi, lower-leg strengthening and activities that challenge coordination," says Dr Lindsay, from Flinders' College of Health and Enablement.

"Staying active is one of the most important things people can do, and small, consistent exercises can help you stay confident, mobile and independent for longer."

The researchers hope the findings will inform better prevention and rehabilitation strategies to reduce falls and support healthy aging.