Aerobic fitness could lower dementia risk by 35%, study finds

New Delhi: High cardiorespiratory fitness could help lower risk of dementia by up to 35 per cent, including in people with a high genetic risk for developing the ageing-related condition, according to a study.

Cardiorespiratory fitness or or aerobic fitness is a measure of how well oxygen is delivered to muscles and organs while performing physical activity. With age, as mucles weaken, the capacity of circulatory and respiratory systems to supply oxygen declines.

Cycling, running and aerobic exercises can help improve cardiorespiratory fitness.

Researchers from Tianjin Medical University, China, and Karolinska Institute, Sweden, found that people having high scores in cardiorespiratory fitness had a higher cognitive function and a lower risk of dementia.

Further, among these individuals, onset of dementia was found to be delayed by up to 1.5 years, or 18 months.

"Our study shows that higher cardiorespiratory fitness is associated with better cognitive function and decreased dementia risk. Moreover, high cardiorespiratory fitness may buffer the impact of genetic risk of all dementia by 35 per cent," the authors wrote in the study published in the British Journal of Sports Medicine.

Maintaining favourable levels of aerobic fitness could be a strategy to prevent dementia, even among people genetically inclined towards developing it, they said.

For the study, the researchers divided a group of over 61,000 people aged 39-70 years and not having dementia into three equal sub-groups according to their cardiorespiratory fitness scores. Over a follow-up period of up to 12 years, 553 people were diagnosed with dementia.

The participants took a six-minute exercise test on a stationary bike at the time of enrolling in the UK Biobank study between 2009 and 2010 for developing cardiorespiratory fitness scores. Cognitive function and a genetic score for developing dementia too were estimated.

Onset of dementia was found to be delayed by about a year and a half among those with high levels of cardiorespiratory fitness, compared to those having low aerobic fitness scores.