Brain stimulation modulates the autonomic nervous system, rating of perceived exertion and performance during maximal exercise
- Alexandre Hideki Okano1,
- Eduardo Bodnariuc Fontes2,
- Rafael Ayres Montenegro3,
- Paulo de Tarso Veras Farinatti3,
- Edilson Serpeloni Cyrino4,
- Li Min Li2,
- Marom Bikson5,
- Timothy David Noakes6
- 1Physical Education Department, Federal University of Rio Grande do Norte (UFRN), Natal, Rio Grande do Norte, Brazil
- 2Department of Neurology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
- 3Physical Education and Sports Institute, Rio de Janeiro State University (UERJ), Rio de Janeiro, RJ, Brazil
- 4Center of Physical Education and Sport, State University of Londrina (UEL), Londrina, Parana, Brazil
- 5Department of Biomedical Engineering, The City College of New York of CUNY, New York, New York, USA
- 6MRC/UCT Research Unit for Exercise Science and Sports Medicine, University of Cape Town (UCT), Cape Town, Western Cape, South Africa
- Correspondence to Professor Alexandre Hideki Okano, Departamento de Educação Física, Universidade Federal do Rio Grande do Norte, Campus Universitário BR 101, Lagoa Nova, CEP 59072-970, Natal, Rio Grande do Norte, Brazil;
- Received 6 August 2012
- Revised 22 October 2012
- Accepted 30 January 2013
- Published Online First 27 February 2013
Background The temporal and insular cortex (TC, IC) have been associated with autonomic nervous system (ANS) control and the awareness of emotional feelings from the body. Evidence shows that the ANS and rating of perceived exertion (RPE) regulate exercise performance. Non-invasive brain stimulation can modulate the cortical area directly beneath the electrode related to ANS and RPE, but it could also affect subcortical areas by connection within the cortico-cortical neural networks. This study evaluated the effects of transcranial direct current stimulation (tDCS) over the TC on the ANS, RPE and performance during a maximal dynamic exercise.
Methods Ten trained cyclists participated in this study (33±9 years; 171.5±5.8 cm; 72.8±9.5 kg; 10–11 training years). After 20-min of receiving either anodal tDCS applied over the left TC (T3) or sham stimulation, subjects completed a maximal incremental cycling exercise test. RPE, heart rate (HR) and R–R intervals (as a measure of ANS function) were recorded continuously throughout the tests. Peak power output (PPO) was recorded at the end of the tests.
Results With anodal tDCS, PPO improved by ∼4% (anodal tDCS: 313.2±29.9 vs 301.0±19.8 watts: sham tDCS; p=0.043), parasympathetic vagal withdrawal was delayed (anodal tDCS: 147.5±53.3 vs 125.0±35.4 watts: sham tDCS; p=0.041) and HR was reduced at submaximal workloads. RPE also increased more slowly during exercise following anodal tDCS application, but maximal RPE and HR values were not affected by cortical stimulation.
Conclusions The findings suggest that non-invasive brain stimulation over the TC modulates the ANS activity and the sensory perception of effort and exercise performance, indicating that the brain plays a crucial role in the exercise performance regulation.