Affective Modulation after High-Intensity Exercise Is Associated with Prolonged Amygdalar-Insular Functional Connectivity Increase

Abstract

Acute moderate exercise has been shown to induce prolonged changes in functional connectivity (FC) within affect and reward networks. The influence of different exercise intensities on FC has not yet been explored. Twenty-five male athletes underwent 30 min of “low”- (35%<lactate threshold (LT)) and “high”- (20%>LT) intensity exercise bouts on a treadmill. Resting-state fMRI was acquired at 3 Tesla before and after exercise, together with the Positive and Negative Affect Scale (PANAS). Data of 22 subjects (3 dropouts) were analyzed using the FSL feat pipeline and a seed-to-network-based analysis with the bilateral amygdala as the seed region for determining associated FC changes in the “emotional brain.” Data were analyzed using a repeated measures ANOVA. Comparisons between pre- and post-exercise were analyzed using a one-sample t-test, and a paired t-test was used for the comparison between “low” and “high” exercise conditions (nonparametric randomization approach, results reported at p<0.05). Both exercise interventions induced significant increases in the PANAS positive affect scale. There was a significant interaction effect of amygdalar FC to the right anterior insula, and this amygdalar-insular FC correlated significantly with the PANAS positive affect scale (r=0.47, p=0.048) in the “high”-intensity exercise condition. Our findings suggest that mood changes after exercise are associated with prolonged alterations in amygdalar-insular FC and occur in an exercise intensity-dependent manner.

Interrelationships between exercise, functional connectivity, and cognition among healthy adults: A systematic review

“…Connectivity between several subcortical structures displays a complex array of interconnections that extend to numerous regions of the human cortex, potentially affecting emotional behavior in addition to cognitive behavior. For instance, Schmitt et al (2020) investigated the immediate effects of exercise intensity on resting‐state functional connectivity between the bilateral amygdala and the right hemisphere (emotional region) of the brain. Results indicated that resting‐state functional connectivity between the bilateral amygdala to the right anterior insula was significant ( p = .03).…”

Aerobic Exercise Decreases Negative Affect by Modulating Orbitofrontal-Amygdala Connectivity in Adolescents

“…On the other hand, exercise could directly decrease the activity of amygdala. Accumulative studies demonstrated the role of amygdala and the brain network involving amygdala [ 19 , 44 ]. A recent fMRI study used a within-subject crossover design to explore amygdala reactivity to explicit and implicit perception of emotional faces in forty young adults after 12-min aerobic exercise, which showed running elicited positive functional connectivity between amygdala and orbitofrontal cortex as well as insula [ 19 ].…”

“…A recent fMRI study used a within-subject crossover design to explore amygdala reactivity to explicit and implicit perception of emotional faces in forty young adults after 12-min aerobic exercise, which showed running elicited positive functional connectivity between amygdala and orbitofrontal cortex as well as insula [19]. Similarly, another study also found the FC between the amygdala and right anterior insula increased after high-intensity exercise intervention, while FC decreased after low-intensity exercise intervention [44]. As an important brain structure of emotion regulation, the amygdala is closely associated with negative mood states including depressive symptoms, and anxiety [45].…”

Exercise Intensity and Brain Plasticity: What’s the Difference of Brain Structural and Functional Plasticity Characteristics Between Elite Aerobic and Anaerobic Athletes?

“…This study systematically compared the whole-brain structural and functional plasticity of aerobic athletes and anaerobic athletes for the first time. Based on previous studies, it can be hypothesized that: (1) Brain structural and functional plasticity is different between elite aerobic athletes (who participated in longterm aerobic training) and anaerobic athletes (who participated in long-term anaerobic training), now that it is known that different intensities of acute exercise have different effects on resting-state network (Schmitt et al, 2019(Schmitt et al, , 2020, it can be speculated that long-term and repetitive stimulation can deepen this difference. (2) These differences may lie primarily at the frontal lobe, temporal lobe, and cerebellum.…”

“…Recent studies have proved that different intensities of 30-min acute exercise have different effects on resting-state functional connectivity ( Schmitt et al, 2019 , 2020 ). Resting-state is not a complete and true “rest” but similar to “intrinsic brain activity” or “spontaneous brain activity.” It is used to distinguish from the task-state, for example, moving fingers, doing cognitive tasks, etc.…”