All of us wish to have a healthy body and a healthy mind, in particular, as we age. When should we start thinking seriously about our health and fitness? Does physical fitness in midlife extend into late life as well? Or should we start focusing on fitness from a younger age?
Research has shown that conditions that affect our cardiovascular health (health of our heart and arteries) such as high blood pressure, high cholesterol, diabetes, and obesity increase our risk of developing heart attack, stroke and dementia. More interestingly, it has been found that these cardiovascular risk factors have different modulating effects on our health at different stages of our life.
For instance, while diabetes, high cholesterol, and obesity have adverse effects on the brain throughout our life, high blood pressure seems to be more harmful in midlife than later in life. This suggests that we should start focusing on our health at least before midlife.
The question then would be –does increased cardiovascular fitness during midlife reduce the risk of dementia, and how far into late life does this protection extend?
According to a 44-year longitudinal population study on Swedish women aged 38-60 years, high cardiovascular fitness levels was found to reduce dementia risk significantly, and delay it by at least 9.5 years.
What we have known from previous research is the strong connection between physical activity and reduced risk for dementia. But the above longitudinal study was the first one of its kind to objectively measure cardiovascular fitness and the risk of dementia in women during midlife.
The study involved 191 participants from the Swedish Population Register, who underwent exercise testing on a stationary bike. Based on how long they could pedal before they got completely exhausted, they were assigned to low, medium or high cardiovascular fitness levels.
Dementia assessments were made periodically during 1968-2012.
The high fitness group showed 88% decrease in dementia incidence. Those who did develop dementia in this group, did so at a higher age (by 11 years), and took 9.5 years longer than medium fitness group to develop it.
Those who developed dementia in the medium fitness group were able to delay it by 5 years. The researchers found a very high dementia incidence among the low fitness group.
Does this suggest that we need to focus on cardiovascular fitness only in midlife? The answer is no, according to another study published in 2015 in Neurology journal.
This study involved young adult participants (average age 25 years) who underwent exercise testing on a treadmill. They were assigned to high, medium, and low cardiorespiratory fitness groups based on how long they could exercise before they developed fatigue.
Those with high cardiorespiratory fitness at age 25 were found to have higher brain volume and better cognitive abilities, indicative of better brain health, 25 years later.
What can we learn from all the above research? The first and foremost point to understand is that regular exercise helps in improving physical fitness and cardiovascular fitness. Secondly the earlier we start working on physical and cardiovascular fitness, the better would be our health in late life. Thirdly, since dementia has no cure at present, the best thing we can do at this time is reduce our risk by focusing on fitness.
Finally, women have a higher lifetime risk of developing dementia than men, and we now have ample scientific evidence to believe that we can reduce our risk significantly by having physical and cardiovascular fitness.
Padmaja Genesh, who holds a bachelor degree in medicine and surgery as well as a bachelor degree in Gerontology, has spent several years teaching and working with health care agencies. A past resident of Red Deer, and a past board member of Red Deer Golden Circle, she is now a Learning Specialist at the Alzheimer Society of Calgary. Please send your comments to firstname.lastname@example.org