Diferenças de gênero no limiar sensitivo para estimulação elétrica nervosa em adultos jovens Gender differences in the sensitive threshold to electrical nerve stimulation in young adults

Abstract

OBJETIVO: Investigar diferenças de gênero no limiar neuronal sensitivo (LNS) para estimulação elétrica nervosa transcutânea (TENS) entre adultos jovens, e os presumíveis efeitos da termoterapia prévia. MÉTODOS: Foram divididos por gênero, 30 estudantes jovens sadios (15 homens e 15 mulheres entre 6/11 ciclo estral) com 22±2 anos de idade. TENS foi aplicada simultaneamente nos joelhos direito e esquerdo dos sujeitos com frequência de 20 Hz e duração de pulso 230µs. A amplitude da corrente elétrica (mǺ) foi aumentada gradativamente para registro do limiar de percepção (LS) e tolerância (LT), antes/após termoterapia. O aquecimento no joelho-D foi realizado por luz infravermelha (250 W) à 0≈70 cm perpendicularmente, e o resfriamento do joelho-E por compressa de gelo, ambos realizados durante 15 minutos. A temperatura tecidual foi registrada por termometria digital. Os dados foram analisados e diferenças estabelecidas em pOBJECTIVE: To investigate gender differences in neuronal sensory threshold (NS) for transcutaneous electrical nerve stimulation (TENS) among young adults, and the probable effects of thermotherapy. METHODS: 30 young healthy students (15 men and 15 women) with 22±2 years old were divided by gender. TENS was applied in both right and left knees of subjects with a frequency of 20 Hz and pulse duration of 230µs. The amplitude of the electric current (mǺ) was gradually increased to record the perception threshold (LS) and tolerance threshold (LT), before/after thermotherapy. The warm R-knee was performed by infrared light (250W) ≈70cm perpendicular, and cooling L-knee with icepack, both carried out for 15 minutes. The tissue temperature was recorded by digital thermometry. The data were analyzed and differences established at p<0.05. RESULTS: The tissue temperature after heat treatments was different (p≤0.05) between genders. The basal LS for TENS was not different between genders, however, thermotherapy raised the NS in both men and women. At the baseline LT was lower (p ≤0.05) in women, however, after thermotherapy it increased (p≤0.05) in both sexes. CONCLUSION: Neuronal sensory threshold for TENS is gender- thermo-dependent in healthy young adults.

Keywords

• Estimulação elétrica nerrvosa
• Hipertermia induzida
• Crioterapia, Limiar sensorial
• Transcutaneous eletric nerve
• Hyperthermia induced, Cryotherapy, Sensory threshold