Short but intense exercise sessions may be more effective for older adults than traditional cardio. A dissertation at Umeå University found this to be true.
Regular physical activity is well-known to have numerous health benefits, but it’s particularly important for older adults. Training can improve several functions that decline with age. However, a significant public health concern is that many seniors are physically inactive. Now, new research has examined the effects of high-intensity training.
“One of the most exciting discoveries in my research is the connection between muscle strength and brain function,” said Sofi Sandström, who authored the dissertation at Umeå University. “When you shorten the sessions and increase the intensity, older adults seem to gain extra benefits for both leg strength and working memory.”
Pulse-Raising Training
Previous studies have shown that high-intensity interval training (HIIT) – which involves extremely short but intense bursts of activity – has promising health effects in younger people. This new research demonstrates how different levels of training intensity impact fitness, brain function, and muscle strength in individuals over 65.
The study included 68 participants between the ages of 66 and 79 who did not regularly exercise. Participants were randomly assigned to two groups and exercised on stationary bikes twice a week for three months. One group completed moderate-intensity cardio for 40-minute sessions, while the other engaged in high-intensity training with short intervals (10 x 6 seconds) during a 20-minute session.
Greater Impact on Leg Strength and Memory
The results showed that both fitness and blood pressure improved to a similar extent in both groups, regardless of whether the training was moderate or high intensity. However, the high-intensity, and significantly shorter, sessions led to better improvements in leg strength and working memory. As these functions often decline with age, Sandström believes this training method is promising.
“Researchers have previously been unsure whether older adults should even train at high intensity, but my results suggest it works just as well as moderate-intensity training,” Sandström said. “controlled high-intensity sessions could be an important option for older adults who want to vary their training.”
Stronger Legs Linked to a Sharper Brain
Cognitive function was assessed in the study using a comprehensive cognitive battery that included several different working memory tests. Brain activation during working memory was also examined, as participants completed a working memory test during an MRI scan.
The study found that increased leg strength was related to both increased activation in the frontal lobe during the working memory test and improved performance on the test. This suggests that muscular adaptation may be an important goal for training aimed at protecting the brain.
Previous research has suggested that age-related changes in the brain’s white matter may limit the effects of traditional cardio on working memory. Individuals with more pronounced changes have often not shown the same improvements. However, the dissertation revealed that high-intensity training improved working memory even in participants with extensive white matter changes.
“This suggests that high-intensity training may be particularly valuable for people with early changes in the brain’s white matter,” Sandström said.
Exercise at Home with a Chair
To craft high-intensity training accessible to a wider group, Sofi Sandström also explored the possibility of exercising at home without advanced exercise bikes.
The high-intensity session was adapted to leverage “chair stand-ups” at a fast pace, which proved to produce a similar immediate physiological response as intense training on a stationary bike.
“The next step is to develop a mobile app that can guide the training sessions and to test the training form on a new group of older adults to observe if the results hold true for those without prior HIIT experience,” Sandström said. “The hope is that the training can eventually be carried out in the home environment.”
Dissertation:
Exercise for the aging brain: or are we just out biking?, Umeå University.
