People in their 60s and 70s who regularly engaged in physical activity, such as walking, had the healthiest hearts in a new study.
Compared to sedentary peers, the older adults in the study who were active had better heart-rate variability a measure of the slight differences in time between each heartbeat that is influenced by the health of both the heart and the nervous system.
Modest physical activity, such as the distance and pace of walking, is important for the hearts electrical well being of older adults, Luisa Soares-Miranda told Reuters Health in an email.
The effects were seen over time, added Soares-Miranda, a researcher at the Harvard School of Public Health in Boston and the Faculty of Sport at the University of Porto in Portugal who led the new research.
In our study, older adults that increased their walking pace or distance had a better heart rate variability when compared with those that decreased their walking pace or distance, she said.
Heart rate variability is a sign of a healthy heart that can respond readily to changing demands and is often used as a measure of fitness for adults of any age.
Previous research has shown a link between exercise, heart rate variability, and lowered cardiovascular risk in groups of middle-aged people, but little is known about whether those ties persist in older adults, the researchers note in the journal Circulation.
Soares-Miranda and her colleagues analyzed data on nearly 1,000 participants in the Cardiovascular Health Study that began in the U.S. in 1989. The men and women were 65 or older at the beginning of the study and were followed for five years.
Study participants were initially evaluated for their health status, medical history and cardiovascular risk factors, and asked about their usual amounts of physical activity, including sports and everyday activities such as gardening, housework and walking.
All the people included in the new analysis had their heart rate variability tested at the beginning and end of the five-year study period.
When the researchers analyzed the data, they divided participants into five groups representing the lowest to the highest amounts of physical activity and found that people in the top fifth also had the most favorable heart-rate variability results.
That was particularly true for those who increased their walking pace or distance over the five years studied.
The results dont prove that the exercise influenced heart rate variability, but the researchers adjusted for several factors, including weight, overall health,