A single session of exercise increases connectivity in sensorimotor-related brain networks: a resting-state fMRI study in young healthy adults

Abstract

Habitual long term physical activity is known to have beneficial cognitive, structural, and neuro-protective brain effects, but to date there is limited knowledge on whether a single session of exercise can alter the brain’s functional connectivity, as assessed by resting-state functional magnetic resonance imaging (rs-fMRI). The primary objective of this study was to characterize potential session effects in resting-state networks (RSNs). We examined the acute effects of exercise on the functional connectivity of young healthy adults (N = 15) by collecting rs-fMRI before and after 20 min of moderate intensity aerobic exercise and compared this with a no-exercise control group (N = 15). Data were analyzed using independent component analysis, denoising and dual regression procedures. Regions of interest-based group session effect statistics were calculated in RSNs of interest using voxel-wise permutation testing and Cohen’s D effect size. Group analysis in the exercising group data set revealed a session effect in sub-regions of three sensorimotor related areas: the pre and/or postcentral gyri, secondary somatosensory area and thalamus, characterized by increased co-activation after exercise (corrected p < 0.05). Cohen’s D analysis also showed a significant effect of session in these three RSNs (p< 0.05), corroborating the voxel-wise findings. Analyses of the no-exercise dataset produced no significant results, thereby providing support for the exercise findings and establishing the inherent test–retest reliability of the analysis pipeline on the RSNs of interest. This study establishes the feasibility of rs-fMRI to localize brain regions that are associated with acute exercise, as well as an analysis consideration to improve sensitivity to a session effect.

Exercise intensity modulates the change in cerebral blood flow following aerobic exercise in chronic stroke

“…The generalizability of the findings, however, may be limited by the characteristics of our sample, such as low stroke impairment or the relatively normal fitness level (i.e., mean nVO 2peak = 88 %) compared to other stroke studies (Smith et al 2012). More frequent heart rate and blood pressure measurements, consideration of arterial carbon dioxide (Ito et al 2000), and exercise-related changes in resting-state functional networks (Rajab et al 2014) may help to further establish links between intensity, post-exercise CBF, and acute changes in cognition and motor function. Finally, while there was no spatial overlap between infarcted areas and CBF responses, lesions may have influenced the results by preventing the detection of exercise-sensitive areas previously identified in healthy adults, including the insula (Williamson et al 2004;MacIntosh et al 2014a).…”

A 12-Week Cycling Training Regimen Improves Gait and Executive Functions Concomitantly in People with Parkinson’s Disease

“…Similar increases, in both white and gray matter, have been reported in a group of older sedentary human adults after participation in a 6-month aerobic training regimen (Colcombe et al, 2006). Furthermore, a recent study using resting state functional magnetic resonance imaging found significant changes in activity in sensorimotor areas in a group of young individuals after 20 min of aerobic exercise (Rajab et al, 2014), while a couple of studies demonstrated that functional brain activity in motor areas increased proportional to the movement rate on a pedaling task executed during scanning (Mehta et al, 2012). Finally, increased SMA activation was observed during motor imagery of locomotor-related tasks (Malouin et al, 2003) as well as during real locomotion as measured by electrophysiological studies showing SMA modulation during walking (Petersen et al, 2012; Wagner et al, 2012, 2014; Seeber et al, 2015).…”

Building a Science of Individual Differences from fMRI

“…Going for a run an hour or less prior to scanning may lead to alterations of baseline physiology [119,120]. Anxiety or stress [121], extended exposure to high altitudes [122], recent sleep quality [123,124], or phase of the menstrual cycle (for women) [125] are all examples of poorly understood vascular and neural factors that may hinder the reliability of fMRI measurements if they are not properly measured and incorporated into a full model [126].…”