Why a walk is better than a bike ride for brain’s blood f low

WALKING is better than cycling for the brain, because striking your feet on the ground boosts blood flow.

A stroll is often seen as gentler exercise than a long bike ride.

But as your foot hits the ground, each step sends backward-flowing pressure waves up the arteries, which boost the brain’s blood circulation.

This makes walking better for cerebral blood flow than cycling, where there is no impact on the feet. It follows numerous studies showing walking can prevent Alzheimer’s disease, which has been linked with reduced blood flow in part of the brain.

Researchers at New Mexico Highlands University say a stroll not only boosts brain function, but may make exercise more enjoyable.

Lead author Dr Ernest Greene said: ‘What is surprising is that it took so long for us to finally measure these obvious hydraulic effects on cerebral blood flow.

‘ There is an optimising rhythm between brain blood flow and ambulating [walking]. Stride rates and their foot impacts are within the range of our normal heart rates (about 120 beats per minute) when we are briskly moving along.’ The scientists took ultrasounds from 12 healthy adults as they stood upright or walked steadily at a rate of a metre per second.

This calculated the speed of blood flow through vessels including the carotid artery to both sides of the brain. Plodding feet sent pressure waves through the arteries, which modify and increase the brain’s blood supply.

The waves were found to synchronise with the heart rate and stride rate to regulate blood circulation to the brain. While the effect was less dramatic than when running, it was greater than when cycling. Until recently, the brain’s blood supply was thought to be involuntarily regulated and largely unaffected by changes in blood pressure caused by exercise.

But the researchers, who presented the study to a meeting of the American Physiological Society, said it suggests brain blood flow is ‘very dynamic’ and depends on pressures in the arteries interacting with ‘pressure pulses from foot impacts’.

The results show that the brain, as well as the heart and muscles, benefit from going for a walk.

The NHS advises people to take 10,000 steps a day to reduce the risk of stroke, heart disease, type 2 diabetes and asthma.

The scientists added that activities increasing blood flow to the brain ‘ may optimise … overall sense of wellbeing during exercise’.

÷TAI chi could help increase brain power for over- 50s, Australian researchers say.

They found a 45-minute session at least once a week helped improve thinking, attention and memory.

Other exercise was ‘similarly effective’ but the Canberra University team said the ancient Chinese practice could help older people unable or unwilling to take on vigorous exercise.

The team assessed 39 studies testing the impact of exercise on over-50s and published findings in the British Journal of Sports Medicine.

‘Optimising rhythm’