Effects of exercise and physical activity on gut microbiota composition and function in older adults: a systematic review

Abstract

Background The characterization and research around the gut microbiome in older people emphasize microbial populations change considerably by losing the diversity of species. Then, this review aims to determine if there is any effect on the gut microbiota of adults older than 65 that starts an exercise intervention or improves physical activity level. Also, this review describes the changes in composition, diversity, and function of the gut microbiota of older subjects that had improved their physical activity level. Methods The type of studies included in this review were studies describing human gut microbiota responses to any exercise stimulus; cross-sectional studies focused on comparing gut microbiota in older adults with different physical activity levels—from athletes to inactive individuals; studies containing older people (women and men), and studies written in English. This review's primary outcomes of interest were gut microbiota abundance and diversity. Results Twelve cross-sectional studies and three randomized controlled trials were examined. Independently of the type of study, diversity metrics from Alpha and Beta diversity remained without changes in almost all the studies. Likewise, cross-sectional studies do not reflect significant changes in gut microbiota diversity; no significant differences were detected among diverse groups in the relative abundances of the major phyla or alpha diversity measures. Otherwise, relative abundance analysis showed a significant change in older adults who conducted an exercise program for five weeks or more at the genus level. Conclusions Here, we did not identify significant shifts in diversity metrics; only one study reported a significant difference in Alpha diversity from overweight people with higher physical activity levels. The abundance of some bacteria is higher in aged people, after an exercise program, or in comparison with control groups, especially at the genus and species levels. There needs to be more information related to function and metabolic pathways that can be crucial to understand the effect of exercise and physical activity in older adults. Trial registration PROSPERO ID: CRD42022331551.

The human gut microbiome and aging

“… 39 In older adults specifically, physical activity-based interventions can cause an increase in health-related taxa but do not impact broad diversity measures. 43 …”

Nutrition and Physical Activity in the Elderly

“…Obese individuals tend to have greater improvements in metabolic parameters associated with obesity (insulin tolerance, plasma triglycerides, and body fat distribution) after dietary intervention. A recent review from 2023 showed in almost all the cross-sectional studies that physical activity alone does not exert significant chang­es in gut microbiota diversity [4], but a combined intervention of exercise and nutrition could be useful to improve physical performance [5] and maintain an efficient microbiome.…”

Effects of Exercise on Gut Microbiota of Adults: A Systematic Review and Meta-Analysis

“…A large body of evidence supports the role of exercise in effectively preventing and treating chronic diseases such as obesity, hypertension, depression, diabetes, respiratory diseases, and cardiovascular diseases [11]. As these diseases have also been associated with specific GM composition and function [12], exercise may be more closely related to intestinal flora than previously thought.…”