title: Relationship between skin temperature and muscle activation during incremental cycle exercise.
abstract: While different studies showed that better fitness level adds to the efficiency of the thermoregulatory system, the relationship between muscular effort and skin temperature is still unknown. Therefore, the present study assessed the relationship between neuromuscular activation and skin temperature during cycle exercise. Ten physically active participants performed an incremental workload cycling test to exhaustion while neuromuscular activations were recorded (via surface electromyography - EMG) from rectus femoris, vastus lateralis, biceps femoris and gastrocnemius medialis. Thermographic images were recorded before, immediately after and 10 min after finishing the cycling test, at four body regions of interest corresponding to the muscles where neuromuscular activations were monitored. Frequency band analysis was conducted to assess spectral properties of EMG signals in order to infer on priority in recruitment of motor units. Significant inverse relationship between changes in skin temperature and changes in overall neuromuscular activation for vastus lateralis was observed (r<-0.5 and p<0.04). Significant positive relationship was observed between skin temperature and low frequency components of neuromuscular activation from vastus lateralis (r>0.7 and p<0.01). Participants with larger overall activation and reduced low frequency component for vastus lateralis activation presented a better adaptive response of their thermoregulatory system by showing fewer changes in skin temperature after incremental cycling test.
authors: Biophysics and Medical Physics Group, Department of Physiology. Faculty of Medicine and Dentistry, University of Valencia, Valencia, Spain; Research Group in Sport Biomechanics (GIBD), Department of Physical Education and Sports, University of Valencia, Valencia, Spain; Applied Neuromechanics Group, Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, RS, Brazil. Electronic address: j.priego.gibd@gmail.com.
authors: Jose I
authors: JI
authors: Priego Quesada
authors: Applied Neuromechanics Group, Laboratory of Neuromechanics, Federal University of Pampa, Uruguaiana, RS, Brazil.
authors: Felipe P
authors: FP
authors: Carpes
authors: School of Physical Education of the Army, Brazilian Army Center for Physical Training, Rio de Janeiro, RJ, Brazil.
authors: Rodrigo R
authors: RR
authors: Bini
authors: Biophysics and Medical Physics Group, Department of Physiology. Faculty of Medicine and Dentistry, University of Valencia, Valencia, Spain.
authors: Rosario
authors: R
authors: Salvador Palmer
authors: Research Group in Sport Biomechanics (GIBD), Department of Physical Education and Sports, University of Valencia, Valencia, Spain.
authors: Pedro
authors: P
authors: Pérez-Soriano
authors: Biophysics and Medical Physics Group, Department of Physiology. Faculty of Medicine and Dentistry, University of Valencia, Valencia, Spain.
authors: Rosa M
authors: RM
authors: Cibrián Ortiz de Anda
mesh_terms: D000328:Adult; D001833:Body Temperature Regulation; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D006801:Humans; D018482:Muscle, Skeletal / Q000502:physiology*; D012881:Skin Temperature; D013817:Thermography; D055815:Young Adult
keywords: Electromyography; Fatigue; Motor control; Thermography; Thermoregulation; Vastus lateralis