title: An empirical comparison of the therapeutic benefits of physical exercise and cognitive training on the executive functions of older adults: a meta-analysis of controlled trials.
abstract: A robust body of aging-related research has established benefits of both physical exercise (PE) and cognitive training (CT) on executive functions related to the activities of daily living of older adults; however, no meta-analysis has compared these treatments.
  
  
  OBJECTIVE
  The current quantitative review involved a comparison of the overall effect sizes of PE and CT interventions on executive functions (Morris, 2008; pre-post-controlled effect size: d(ppc)), while also exploring contextual moderators of treatment outcomes.
  
  
  METHODS
  A systematic review identified 46 studies (23 PE, 21 CT, and 2 both) meeting inclusion criteria (i.e., controlled interventions, executive-related outcomes, mean ages 65+, information to calculate d(ppc)).
  
  
  RESULTS
  The weighted mean dppc values came to 0.12 (p < .01) for PE and 0.24 (p < .01) for CT. Treatment effects differed based on executive constructs for CT, with problem solving presenting the highest d(ppc) (0.47, p < .01). Notably, PE produced similar effect sizes across distinct executive functions. Treatment characteristics (e.g., session length/frequency) did not predict effect sizes. CT had a significant benefit on healthy participants (0.26, p < .01), but cognitively impaired samples did not experience a significant effect.
  
  
  CONCLUSIONS
  Both treatments improved executive functions, but CT presented a potential advantage at improving executive functions. Improvements in executive functions differed depending on construct for CT, whereas each construct produced similar, modest effect sizes for PE. Publication bias and study quality variability potentially bias these conclusions, as lower quality studies likely produced inflated effect sizes.
authors.affiliation: Department of Psychology.
authors.forename: Justin E
authors.initials: JE
authors.lastname: Karr
authors.affiliation: Department of Psychology.
authors.forename: Corson N
authors.initials: CN
authors.lastname: Areshenkoff
authors.affiliation: Department of Psychology.
authors.forename: Philippe
authors.initials: P
authors.lastname: Rast
authors.affiliation: Department of Psychology.
authors.forename: Mauricio A
authors.initials: MA
authors.lastname: Garcia-Barrera
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003071:Cognition; D003072:Cognition Disorders / Q000517:prevention & control / Q000628:therapy*; D000066492:Cognitive Aging / Q000523:psychology; D018849:Controlled Clinical Trials as Topic; D056344:Executive Function; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome