Intermittent low-intensity and moderate-intensity exercise effects on cognition in community-dwelling older adults: a pilot study exploring biological mechanisms

Swathi Gujral; Judy L Cameron; Kayla Conaty; Sumer Ziady; Amrita Sahu; John M Jakicic; Renee J Rogers; Caterina Rosano; Abbe N Vallejo; Kirk I Erickson; Tamer S Ibrahim; Howards Aizenstein; Charles F Reynolds 3rd; Meryl A Butters

doi:10.3389/fnagi.2024.1432909

Intermittent low-intensity and moderate-intensity exercise effects on cognition in community-dwelling older adults: a pilot study exploring biological mechanisms

Front Aging Neurosci. 2024 Oct 17:16:1432909. doi: 10.3389/fnagi.2024.1432909. eCollection 2024.

Authors

Swathi Gujral^{1

2}, Judy L Cameron¹, Kayla Conaty², Sumer Ziady², Amrita Sahu^{3

4}, John M Jakicic⁵, Renee J Rogers⁵, Caterina Rosano⁶, Abbe N Vallejo¹, Kirk I Erickson^{7

8}, Tamer S Ibrahim⁹, Howards Aizenstein^{1

2

9}, Charles F Reynolds 3rd^{1

2}, Meryl A Butters^{1

2}

Affiliations

¹ Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
² Western Psychiatric Hospital, University of Pittsburgh Medical Center, Pittsburgh, PA, United States.
³ Department of Physical Medicine and Rehabilitation, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States.
⁴ Department of Environmental and Occupational Health, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, United States.
⁵ Department of Internal Medicine, Division of Physical Activity and Weight Management, University of Kansas Medical Center, Kansas, KS, United States.
⁶ Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA, United States.
⁷ Department of Neuroscience, AdventHealth Research Institute, Orlando, FL, United States.
⁸ Department of Psychology, University of Pittsburgh, Pittsburgh, PA, United States.
⁹ Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, United States.

Abstract

Background/objective: To examine the cognitive benefits of 6 months of prescribed intermittent exercise (10-min bouts totaling 150 weekly minutes) in community-dwelling older adults, comparing effects of low-intensity movement (LIM) and moderate-intensity aerobic exercise (aerobic exercise; AE) training; and exploring biological mechanisms of exercise-related cognitive improvement.

Method: Twenty-five adults (>60 years old) participated in a 6-month controlled trial and were randomized into LIM or AE intermittent training. Cognition was assessed using a neuropsychological test battery including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), California Verbal Learning Test, 2nd Edition (CVLT-II), and Delis-Kaplan Executive Function System (D-KEFS). Neuroimaging measures were collected using a 7 T human MRI scanner. Serologic neurotrophic and inflammatory factors were analyzed using Luminex multiplex assays [brain derived neurotrophic factor (BDNF); vascular endothelial growth factor (VEGF)]; interleukin-6 (IL-6), C-reactive protein (CRP), plasminogen activator inhibitor (PAI-1).

Results: LIM and AE intermittent training had dissociable effects on cognition, with LIM resulting in improved learning and memory and AE resulting in improved executive functioning. Intervention groups differed on change in cognitive performance on CVLT-II learning and D-KEFS trail making test. Increase in right dorsolateral prefrontal cortex (DLPFC) surface area was linked to executive improvement (i.e., phonemic fluency) regardless of intervention group. A decline in circulating PAI-1 was linked to learning and memory improvement in response to LIM over 6 months.

Conclusion: Moderate-intensity AE and LIM intermittent training likely have distinct cognitive benefits, though low-intensity activity is often included as a control group in exercise trials in aging.

Keywords: aging; brain; cognition; exercise; inflammation.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. The Healthy Brain Aging Study was supported by the Aging Institute of UPMC Senior Services and the University of Pittsburgh.