The combination of low-intensity resistance exercise and electrical muscle stimulation effectively enhances executive...

Resistance exercise enhances executive function (EF) more effectively at moderate or higher intensities than at low intensity resistance exercise (LRE), probably with increased neural activity and lactate production to meet brain energy demands. Given that LRE remains widely applicable with less perceived exertion, and electrical muscle stimulation (EMS) increases lactate production and neural activation, we investigated whether combining LRE with EMS (LRE-EMS) effectively enhances EF, without increasing perceived exertion.

A crossover randomized study.

Seventeen young men participated in a crossover randomized study to assess the cognitive effects of LRE alone, EMS alone, and LRE-EMS. The LRE protocol involved knee extensions at 40% one-repetition maximum for 4 sets of 10 repetitions. During the EMS condition, the participants remained seated for 260 s to match the duration of the other conditions, with EMS applied to the lower limb muscles. Subjective perceptions of exertion and fatigue during exercise were recorded.

IC and lactate were measured at baseline, immediately postexercise, and 15 min postexercise. The LRE condition did not significantly increase IC (p = 0.100), whereas LRE-EMS resulted in significant IC improvements immediately and 15 min postexercise (both p < 0.001), with greater lactate increases compared to LRE and EMS. EMS demonstrated significant IC improvement at 15 min postexercise (p = 0.022).

Perceived exertion and fatigue were greater with LRE-EMS compared with LRE and EMS. These findings suggest that LRE combined with EMS and EMS alone are effective strategies for cognitive improvement, but increased perceived exertion still exists.