High-intensity workouts may improve memory performance in older adults, according to a study published in the journal Applied Physiology, Nutrition and Metabolism. The findings may be critical for developing new treatment plans for dementia and cognitive decline.

Researchers at McMaster University recruited 64 sedentary older adults, ages 60–88, and monitored them for 12 weeks. Participants were divided into three groups:

  • high-intensity interval training (HIIT)
  • moderate-intensity continuous training (MICT)
  • stretching only (control group)

The HIIT group performed four sets of high-intensity exercise on a treadmill for 4 minutes, followed by a recovery period. The MICT group completed one set of moderate-intensity aerobic exercise for about 50 minutes.

To measure changes in memory, researchers examined the function of newborn neurons generated by exercise, which are ideal for forming new connections and new memories. Results showed that older adults in the HIIT group had the highest increase in high-interference memory (which, for example, allows you to differentiate a car from another of the same make and model) and a 30% improvement in memory performance, compared with the MICT and control groups, which saw no improvement, on average.

Study authors concluded that fitness levels are directly correlated with memory improvement and that intensity is a critical factor when using exercise to mitigate dementia.

“There is urgent need for interventions that reduce dementia risk in healthy older adults. Only recently have we begun to appreciate the role that lifestyle plays, and the greatest modifying risk factor of all is physical activity,” says Jennifer Heisz, lead author of the study and associate professor in the Department of Kinesiology at the university.

Though research is pointing to exercise as an effective intervention for dementia and cognitive decline, guidelines do not yet exist. “Our hope is this research will help form those guidelines,” Heisz says.

The study is available at http://dx.doi.org/10.1139/apnm-2019-0495.