Just 4 sets of four-minute-long bursts of intense exercise was all it took for sedentary people aged 60 -88 to get an improvement in memory scores of up to 30%.
They worked out three times a week for 3 months, and the short sharp sets were better than 50 minutes of moderate exercise. Five hundred million years of evolution will do that — hone organisms to adapt to common stressors. And even if don’t need to outrun lions very often now, we still carry the genes that did.
This won’t surprise people who’ve been reading medical research papers. High Intensity Interval Training (HIIT) appears to be good for fat loss, anxiety, depression, improves blood vessel function, may slow Parkinsons, and colon cancer, is quicker, can restore glucose uptake in diabetic muscles in just two weeks.
Obviously the 30% memory boost mostly happens to people who start out sedentary. There may not be such spectacular gains for people who are already semi fit. But it only took 12 weeks.
Researchers at McMaster University who examine the impact of exercise on the brain have found that high-intensity workouts improve memory in older adults.
Researchers suggest that intensity is critical. Seniors who exercised using short, bursts of activity saw an improvement of up to 30% in memory performance while participants who worked out moderately saw no improvement, on average.
“This work will help to inform the public on exercise prescriptions for brain health so they know exactly what types of exercises boost memory and keep dementia at bay,” she says.
For the study, researchers recruited dozens of sedentary but otherwise healthy older adults between the ages of 60 and 88 who were monitored over a 12-week period and participated in three sessions per week. Some performed high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT) while a separate control group engaged in stretching only.
The HIIT protocol included four sets of high-intensity exercise on a treadmill for four minutes, followed by a recovery period. The MICT protocol included one set of moderate-intensity aerobic exercise for nearly 50 minutes.
To capture exercise-related improvements in memory, researchers used a specific test that taps into the function of the newborn neurons generated by exercise which are more active than mature ones and are ideal for forming new connections and creating new memories.
They found older adults in the HIIT group had a substantial increase in high-interference memory compared to the MICT or control groups. This form of memory allows us to distinguish one car from another of the same make or model, for example.
Researchers also found that improvements in fitness levels directly correlated with improvement in memory performance.
“It’s never too late to get the brain health benefits of being physically active, but if you are starting late and want to see results fast, our research suggests you may need to increase the intensity of your exercise,” says Heisz.
She cautions that it is important to tailor exercise to current fitness levels, but adding intensity can be as simple as adding hills to a daily walk or increasing pace between street lamps.
I don’t usually put these on the blog, but figure plenty of readers here would care about their brain health. For those who do read medical papers, in this case BDNF, which people thought might be important, was not found to be involved in the gains, leaving the mechanism “unknown”.
Obviously, best start slower and ramp up. Years ago I found the UNSW Sprinterval system of 8 seconds fast, 12 seconds slow on an elliptical was a great way to raise that heart rate. It was easy to ramp it up in a saw-tooth pattern. But it could work with cycling, running, or stair climbing. Readers might like to share what works for them. As the cliche goes, the best exercise is the one you do.
Kovacevic et al (2019) The effects of aerobic exercise intensity on memory in older adults. Applied Physiology, Nutrition, and Metabolism, 2019; DOI: 10.1139/apnm-2019-0495