Intensity-dependent effects of cycling exercise on corticospinal excitability in healthy humans: a pilot study

<div><p>Abstract Aims the aim of this study was to verify the effects of different intensities of locomotor exercise on corticospinal excitability. Methods 18 healthy subjects (27.6 ± 6.5 years,) participated in a design study of three different exercise protocols on a cycle ergometer: (i) 10 min at 75% Wmax (high intensity); (ii) 15min at 60% Wmax (moderate intensity) or (iii) 30 min at 45% Wmax (low intensity). The protocols of lower body cycling were assigned in random order in separate sessions. A control session was done with subjects at rest. Corticospinal excitability was assessed before (baseline) and every 5 min for 15min after the end of exercise/rest (time: 0, 5, 10 and 15) by measurement of the motor evoked potential (MEP) elicited by transcranial magnetic stimulation in the relaxed first-dorsal interosseus muscle. Results Compared to the resting session, a significant decrease (64%) in the motor evoked potential amplitudes was found only in the session of exercise of high intensity. This result seems depend on the level of physical activity of subject. No change was found after rest, low and moderate exercises. Conclusions These findings suggest that changes in the corticospinal excitability depend on exercise intensity and level of physical activity of subjects.</p></div

BORN TO RUN: THE IMPORTANCE OF EXERCISE FOR THE BRAIN HEALTH

<p></p><p>ABSTRACT The evolutionary hypothesis of endurance running states that movement played a crucial role in the emergence of typically human anatomical features, as well as in the shaping and structure of the human brain. The close relationship between exercise and human evolution is evidenced by the fact that inactivity make us sick. Effectively, the human body, including the brain, has evolved to withstand extended periods of cardiovascular stress. Movement is so essential to the brain that regular physical activity is imperative for it to function properly. Studies have shown that aerobic exercise increases neuron proliferation, neurotrophic factors synthesis, gliogenesis, synaptogenesis, regulates neurotransmission and neuromodulation systems, and reduce systemic inflammation. All of these effects have a significant impact on improving mental health, reducing age-related gray matter decline, and improving cognitive functions. Thus, the purpose of this article is to present an update on the subject of physical exercise and mental health. Given the recent advances presented in this manuscript on the neurobiology of exercise and its therapeutic and economic potential for the general population, it is expected that future research that correlate basic studies with psychological variables and imaging studies may elucidate the mechanisms by which exercise improves brain health.</p><p></p