In a recent study published within the journal Scientific Reports, researchers explored how changes in day by day step counts and variability affect cognitive function in older adults during a 10-week physical activity intervention.

Study: Association between changes in habitual stepping activity and cognition in older adults. Image Credit: SibRapid / Shutterstock

Background 

Aging often results in cognitive decline, particularly in executive functions and inhibitory control, that are early indicators of conditions like Alzheimer’s disease. Engaging in regular physical activity can reduce and even reverse these declines in older adults. Because the population ages, identifying strategies to preserve cognitive function becomes crucial. While structured exercise in controlled settings has been linked to cognitive health, the consequences of habitual, day by day physical activity on cognition remain underexplored. Further research is required to make clear the mechanisms linking physical activity patterns to cognitive improvements and to ascertain customized intervention strategies for diverse aging populations.

Concerning the study 

In the current study, 43 older adults were recruited, with 37 completing resulting from incomplete stepping data. Participants were over 55, in a position to walk independently, cognitively healthy, and free from significant health issues, though some were on medication. They engaged in a 10-week intervention focused on improving cognitive function through group aerobic and resistance activities, aligning with a dynamic socio-ecological model. Participants committed to a minimum of 150 minutes of moderate-to-vigorous activity weekly, with adherence verified by activity logs.

Activity was monitored with Fitbit devices, requiring consistent wear for accurate step count and variability data. Step count validity and variability (using average real variability, ARV) were assessed, specializing in the day-to-day differences in activity levels.

Physical and cognitive assessments pre- and post-intervention included heart rate, blood pressure, body mass index, a six-minute walk test for aerobic fitness, and a computerized Stroop task for cognitive function. The Stroop task evaluated processing speed, inhibitory control, and cognitive flexibility through different stages, with high accuracy and response times recorded.

Data evaluation, adhering to normality checks and parametric statistics, modeled step counts and variability non-linearly, assessing changes in physical and cognitive measures via paired t-tests and Evaluation of Covariance (ANCOVA), and adjusting for demographic aspects. Regression analyses explored the connection between activity changes and cognitive performance, with statistical significance set at p < 0.05.

Study results 

On this study, the vast majority of participants were female (33 out of 37), and all demonstrated cognitive health with Mini-Mental State Examination (MMSE) scores exceeding 24. Following the intervention, a big reduction in body mass and body mass index was observed alongside a rise in distance covered in the course of the six-minute walk test (6MWT), indicating physical improvements (all, p < 0.001).

Evaluation of stepping data revealed that total step counts increased and day-to-day step variability decreased over the course of the 10-week intervention. These changes were most pronounced initially and end of the period, with the info fitting best to a cubic model, signifying a non-linear relationship in each total steps taken and within the variability of those steps from daily. The intervention increased overall physical activity levels, as evidenced by higher step counts while promoting more consistent activity patterns amongst participants, as shown by reduced variability in day-to-day step counts.

Cognitive outcomes measured through a computerized Stroop task before and after the intervention revealed notable improvements. Specifically, response times in the course of the easy naming condition were faster post-intervention, indicating enhanced processing speed. Although the inhibition condition didn’t significantly improve, the switching condition, which tests cognitive flexibility and is taken into account probably the most difficult, exhibited faster completion times post-intervention. 

When examining the connection between changes in physical activity and cognitive performance, the study found no significant association between the rise in total step counts and enhancements in response time for any of the Stroop task conditions (naming, inhibition, and switching). Nonetheless, a big positive association was observed between reductions in day-to-day step variability and faster response times within the switching condition. 

Conclusions 

To summarize, this study confirmed that stabilizing day by day step variability, reasonably than increasing total step count, led to faster response times within the Switching task of the Stroop test, indicating improved cognitive flexibility in older adults. This means promoting consistent day by day physical activity as a possible strategy for enhancing executive function. The Stroop task showed that such cognitive flexibility improvements could significantly lower the danger of cognitive disorders. The findings challenge current physical activity guidelines by suggesting that day by day consistency, alongside a high variety of steps, may higher support cognitive health in older adults. This personalized physical activity intervention increased average step counts, reduced variability, and enhanced cognitive flexibility, indicating its potential as a model for encouraging consistent day by day activity amongst older adults.