A randomized controlled trial to unveil the influence of an exercise intervention on brain integrity and gut...

Exercise intervention programs enhance physical fitness, cognition, neuroimaging measures, and alter the structure of the gut microbiome in individuals without HIV. However, interventional studies exploring the effects of exercise in persons with HIV (PWH) have not included neuroimaging or gut microbiome analyses.

A randomized controlled trial conducted at Washington University in St. Louis, MO, USA.

65 PWH (aged ≥40 years, self-reported sedentary lifestyle) were randomly assigned to a 6-month cardiorespiratory and resistance training (EXS) or stretching control (SIS) intervention in a 2 : 1 ratio. Longitudinal change in cognition, cerebral blood flow (CBF), physical and cardiorespiratory fitness, and gut microbiome diversity and composition were examined among participants ( n  = 62) who completed any portion of the intervention (ClinicalTrials.gov: NCT02663934).

Better fitness and better cognitive performance were associated with greater phylogenetic diversity in gut microbiome composition at baseline. Longitudinal findings indicated slight but significant improvements in psychomotor speed and executive function, reductions in body mass index, improvements in physical fitness, and increased gut microbiome diversity. These changes were observed regardless of assigned intervention group. There were no observed changes in CBF for either group.

These findings highlight physical fitness as a modifiable factor in PWH that may improve cognitive performance and change gut microbiome composition. Both interventions were beneficial, suggesting light stretching exercise or study participation alone could have been sufficient to introduce positive cognitive shifts in previously sedentary PWH. Longer interventions with more participants are needed to identify changes in neuroimaging metrics related to brain integrity.