Investigating the Effect of High Intensity Interval Training and Structured Exercise on Cognitive Function Among Older Adults

Background and Purpose: As global demographics shift toward an aging population, the World Health Organization (2024) projects that by 2050, the number of people worldwide over the age of 60 will surpass 2.1 billion, with those aged 80 years or older expected to triple to 426 million¹. “Within this population, the prevalence of mild cognitive impairment (MCI) in adults over 60 years old ranges from 6.7% to 25.2%, with an annual rate of progression from MCI to dementia estimated between 5% to 17%”². This demographic transition presents unprecedented challenges in maintaining cognitive health among older adults. Methods: This study examined the cognitive effects of high-intensity interval training compared to a prescribed fitness plan among UWEC’s Community Fitness Program (CFP) members aged 45-80. Participants of the intervention group (high intensity interval training) and the control group were asked to commit to 2-3 workouts a week for four weeks. To evaluate cognitive function, participants completed a Stroop test, which evaluates an individual’s speed and accuracy during cognitive interference. Three Stroop tests were conducted throughout the semester: baseline, post-intervention, and two weeks post-exercise to evaluate the effects of detraining. Results: The two-way repeated measures ANOVA (p<.05) indicated voice portion of Stroop assessment (pretest, posttest, and follow-up) and Group (control, intervention) were not significant predictors of improving reaction time, F(2,34) = 4.280, p =.022. and F(1,17) = 1.228, p = .283, respectively.  In addition, no significant interaction effect was examined, F(2,34,30) = 2.352, p = .110. The two-way repeated measures ANOVA (p<.05) indicated the keyboard portion of Stroop assessment (pretest, posttest, and follow-up) and Group (control, intervention) were not significant predictors of improved reaction time F(1.424,24.214) = 5.72, p = .016 and F(1,17) = 0.01, p = .936, respectively.  In addition, no significant interaction effect was examined, F(1.424,24.214) = 1.176, p = .310.  Conclusions: Regular exercise intervention, no matter the type, has proven to be effective at preventing both physical and cognitive impairments in middle to older aged adults. This leads to greater choice autonomy as individuals can choose exercise modalities based on personal preferences. This in turn leads to greater adherence and overall improved cognitive and physical health markers.