#LOW INTENSITY EXERCISE SKIN#

Previous animal studies have demonstrated that physical activity upregulates the secretion of growth factors including brain-derived neurotrophic factor (BDNF) ( Neeper et al., 1995, 1996), insulin-like growth factor 1 ( Trejo et al., 2001 Cetinkaya et al., 2013), vascular endothelial growth factor ( Latimer et al., 2011) and nerve growth factor ( Ding et al., 2004). Regular physical activity or aerobic exercise is well-known to increase brain plasticity ( Cotman and Berchtold, 2002 Cotman and Engesser-Cesar, 2002 Kramer and Erickson, 2007 Hillman et al., 2008), which is a process indispensable to learning and memory. In conclusion, acute low-intensity pedaling modulates M1 intracortical circuits of both exercised and non-exercised areas, without affecting corticospinal and spinal excitability. The single motor-evoked potential, resting motor threshold, LICI, SICF, and spinal excitability did not change following exercise. After exercise, ICF in the M1 hand area was lower than in the control experiment, but was not significantly different to baseline.

We found that acute low-intensity aerobic exercise decreased SICI and SAI in the M1 hand and leg areas. Intracortical facilitation (ICF) and short-interval intracortical facilitation (SICF) were measured to assess M1 excitatory circuits. Short- and long-interval intracortical inhibition (SICI and LICI), and SAI were measured to assess M1 inhibitory circuits. Participants performed 30 min of low-intensity pedaling exercise or rested while sitting on the ergometer. Transcranial magnetic stimulation was applied over the M1 non-exercised hand and exercised leg areas in Experiments 1, 2, respectively.

#LOW INTENSITY EXERCISE SKIN#

In Experiment 3, skin temperature was also measured throughout the experiment. Intracortical excitability of M1 (Experiments 1, 2) and spinal excitability (Experiment 3) were measured before and after acute low-intensity aerobic exercise. The aim of this study was to investigate whether acute low-intensity aerobic exercise modulates intracortical circuits in the M1 hand and leg areas. In addition, no previous studies have investigated the effect of acute aerobic exercise on short-latency afferent inhibition (SAI). However, whether acute low-intensity aerobic exercise can also modulate M1 intracortical excitability, particularly intracortical excitatory circuits, remains unclear. Recent studies have reported that acute aerobic exercise modulates intracortical excitability in the primary motor cortex (M1).

6Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.

5Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan.

4Field of Health and Sports, Major in Health and Science, Niigata University of Health and Welfare, Niigata, Japan.

3Department of Health and Sports, Niigata University of Health and Welfare, Niigata, Japan.

2Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan.

1Major in Health and Welfare, Niigata University of Health and Welfare, Niigata, Japan.

Yudai Yamazaki 1,2*, Daisuke Sato 2,3, Koya Yamashiro 2,3, Saki Nakano 2,4, Hideaki Onishi 2,5 and Atsuo Maruyama 6

Low intensity exercise