The performance of a maximal graded exercise test triggers only modest neuroplastic changes in patients with chronic stroke. However, a single bout of high-intensity interval training performed immediately after motor practice improves skill retention, which could potentially accelerate motor recovery in these individuals.

Purpose Video gamers exceeding screen-time limits are at greater risk of experiencing health issues associated with physical inactivity. Demonstrating that exercise has positive effects on video game performance could promote physical activity among video gamers. We investigated the short-term effects of a single session of cardiovascular exercise on the performance of the popular video game League of Legends (LoL) and explored psychosocial mechanisms. Methods Twenty young video gamers played a customized LoL task preceded by a short bout of high-intensity interval training or a period of rest. The two conditions were administered on two separate days in a randomized counterbalanced fashion. Video game performance was assessed as the total number of targets eliminated as well as accuracy, defined as the ability to eliminate targets using single attacks. Short-term changes in affect after exercise as well as exercise enjoyment were also assessed. Results Exercise improved (P = 0.027) the capacity to eliminate targets (mean ± SEM, 121.17 ± 3.78) compared with rest (111.38 ± 3.43). Exercise also enhanced accuracy (P = 0.019), with fewer targets eliminated with more than one attack after exercise (1.39 ± 0.39) compared with rest (2.44 ± 0.51). Exercise increased positive affect by 17% (P = 0.007), but neither affect nor exercise enjoyment was associated with total number of targets eliminated or accuracy. Conclusion A short bout of intense cardiovascular exercise before playing LoL improves video game performance. More studies are needed to establish whether these effects are generalizable to other video games, whether repeated bouts have summative effects, and to identify underlying mechanisms.

Unilateral arm movements require trunk stabilization through bilateral contraction of axial muscles. Interhemispheric interactions between primary motor cortices (M1) could enable such coordinated contractions, but these mechanisms are largely unknown. Using transcranial magnetic stimulation (TMS), we characterized interhemispheric interactions between M1 representations of the trunk-stabilizing muscles erector spinae at the first lumbar vertebra (ES L1) during a right isometric shoulder flexion. These interactions were compared with those of the anterior deltoid (AD), the main agonist in this task, and the first dorsal interosseous (FDI). TMS over the right M1 elicited ipsilateral silent periods (iSP) in all three muscles on the right side. In ES L1, but not in AD or FDI, ipsilateral motor evoked potential (iMEP) could precede the iSP or replace it. iMEP amplitude was not significantly different whether ES L1 was used to stabilize the trunk or was voluntarily contracted. TMS at the cervicomedullary junction showed that the size of cervicomedullary evoked potential was unchanged during the iSP but increased during iMEP, suggesting that the iSP, but not the iMEP, is due to intracortical mechanisms. Using a dual-coil paradigm with two coils over the left and right M1, interhemispheric inhibition could be evoked at interstimulus intervals of 6 ms in ES L1 and 8 ms in AD and FDI. Together, these results suggest that interhemispheric inhibition is dominant when axial muscles are involved in a stabilizing task. The ipsilateral facilitation could be evoked by ipsilateral or subcortical pathways and could be used depending on the role axial muscles play in the task. The mechanisms involved in the bilateral coordination of axial muscles during unilateral arm movement are poorly understood. We thus investigated the nature of interhemispheric interactions in axial muscles during arm motor tasks in healthy subjects. By combining different methodologies, we showed that trunk muscles receive both inhibitory and facilitatory cortical outputs during activation of arm muscles. We propose that inhibition may be conveyed mainly through interhemispheric mechanisms and facilitation by subcortical mechanisms or ipsilateral pathways.