Does whole-body electrical muscle stimulation combined with strength training promote morphofunctional alterations?

OBJECTIVES: The aim of this study was to evaluate the effects of 8 weeks of strength training (ST) combined with whole-body electrical stimulation (EMS) on morphofunctional adaptations in active individuals. METHODS: Fifty-eight volunteers were randomly distributed into the following groups: an untrained control (UN) group (n=16), an ST group (n=21) or an ST combined with EMS (ST+EMS) group (n=21). Both intervention groups (the ST and ST+EMS groups) performed 3 exercises (biceps curl, back squats and high-pulley tricep extensions) twice a week for 8 weeks. The subjects performed 3 sets of 8 to 12 maximum repetitions (MRs) with a 90-second rest duration between sets. The ST+EMS group performed the resistance training exercises wearing a whole-body suit that provided electrical stimulation at frequencies between 80-85 Hz, with a continuously bipolar impulse duration and pulse breadth of 350 µs. The intensity for each muscle group was controlled by Borg's category ratio (CR)-10 scale; the intensity started at 5-6 and eventually reached 7-8. One-repetition maximum strength (1RM) and muscle thickness (MT) were measured before and after the training intervention. MT was evaluated in the biceps brachii (BB), triceps brachii (TB), and vastus lateralis (VL). RESULTS: No differences (p>0.05) were found between the ST and ST+EMS groups. Improvements (p<0.05) in the absolute values of the morphofunctional parameters after the training protocol were observed. Significant differences were found between both the intervention groups and the UN group (p<0.05). The ST+EMS group presented high percentage changes (p<0.05) in muscular strength for the 1RMsquat (43.2%, ES=1.64) and the MT of the BB (21.6%, ES=1.21) compared to the ST (20.5%, ES=1.43, 11.9%, ES=0.77) group. CONCLUSIONS: Our data suggest that the combination of ST+EMS may promote alterations in muscle strength and MT in healthy active subjects.

Comparação da força, flexibilidade e resistência de mulheres praticantes de treinamento de força e praticantes de Pole Dance / Strength, flexibility and resistance comparison between woman strength training practitioners and Pole Dance practitioners

Praticar atividade física promove melhora na qualidade de vida e na aptidão física. Neste sentido, o treinamento de força e o pole dance são modalidades que muitas mulheres buscam para melhorar a força, flexibilidade e a resistência abdominal. A partir disso, o objetivo do presente estudo foi comparar a força, a flexibilidade e resistência entre mulheres que praticam treinamento de força e que praticam pole dance. Foram selecionadas 22 mulheres praticantes de treinamento de força (n=11) e de pole dance (n=11). As mesmas foram submetidas ao teste de 1RM de extensão de joelhos, teste de preensão manual com dinamômetro, teste de flexibilidade no banco de Wells e teste de resistência abdominal em 1 minuto. Não foram observadas diferenças significativas para a idade, massa corporal, estatura, IMC e % de gordura entre os grupos avaliados (p>0,05). As praticantes de treinamento de força apresentaram melhores níveis de força de membros inferiores (p=0,026) enquanto as praticantes pole dance melhor flexibilidade (p=0,003). Para preensão manual e resistência abdominal não foram observadas diferenças significativas entre os grupos (p>0,05). Pode-se concluir que o treinamento de força tende a proporcionar maior força de membros inferiores enquanto o pole dance favorece a flexibilidade...(AU)

Physical activity practice promotes improvement of life quality and physical performance. Thus, the strength training and pole dance are exercise forms that many women seek when it comes to strength, flexibility and resistance. The aim of this study was to compare the strength, flexibility and abdominal resistance between women strength training practitioners and pole dance practitioners. Were selected 11 women practitioners of strength training and 11 women practitioners of pole dance. Subjects were submitted to the one maximal repetition test of knee extension, handgrip dynamometer test, flexibility test using bank Wells and abdominal resistance test in one minute. No significant difference was observed for age, body weight, height, body mass index and fat percentage between groups (p> 0.05). The strength training practitioners had higher levels of lower limbs strength (p = 0.026) while pole dance practitioners showed better flexibility (p = 0.003). For handgrip and abdominal resistance no significant differences were observed between groups (p> 0.05). We concluded that the practice of strength training tends to provide greater lower limbs strength while the pole dance favors flexibility...(AU)

Acute effects of local vibration on the neuromuscular responses / Efeito agudo da vibração local sobre as respostas neuromusculares

The aim of this study was to evaluate acute neuromuscular responses to local vibrations (LV) exposure through monitoring of imposed acceleration. Nineteen healthy males (age = 22.43 ± 2.76 years; body mass = 76.4 ± 12.94 kg; height = 175 ± 6.76 cm) performed an elbow flexion isometric exercise (Scott bench) in two experimental conditions: simple isometric exercise (Control - CON) and vibrating isometric exercise (Local Vibration - LV; Frequency = 20.01 ± 0.13, displacement = 2 - 5 mm). Protocols consisted of 5 maximal voluntary contractions of 12 seconds each and five minutes of recovery between series with (LV) or without vibration (CON). During the exercise, individuals were seated on the bench with the dominant arm resting on the bench support at an approximate angle of 45º between shoulder flexion and the torso. Strength parameters (Rate of Force Development - RFD, p = .030; Peak Force - PF, p = .027; and Fatigue Index - FI, p = .001) significantly increased in LV compared to CON. For EMG parameters, significant changes were only observed for highest value of increase rate of the EMG signal - RER (p = .041), median frequency of EMG signal between peak force and force at the end of the isometric action - MFFbic (p = .045) (agonist) and root mean square of EMG signal of peak force at the end of the isometric action - RMSFtric (p <.001) (antagonist). The addition of local vibrations in resistance training induced an increase in maximal strength, explosive strength and reduced the capacity to sustain strength generation.

O objetivo deste estudo foi avaliar as respostas neuromusculares durante o exercício com a variação dos parâmetros de vibração local. Foram recrutados 19 indivíduos saudáveis do gênero masculino (idade = 22,43 ± 2,76 anos; massa corporal = 76,4 ± 12,94 kg; altura = 175 ± 6,76 cm) que executaram o exercício isométrico em duas situações experimentais: somente o exercício isométrico (Controle); exercício com a adição de vibrações locais (LV; Frequência = 20 ± 3Hz, Deslocamento = 2 - 5 mm). Os parâmetros de força foram significativamente aumentados no tratamento LV comparados ao tratamento controle (RFD, p = ,030; PF, p = ,027; and FI, p = ,001). Para os parâmetros de atividade eletromiográfica, foram observadas alterações significativas para a RER (p = ,041), MFFbic (p = ,045) no músculo bíceps braquial (agonista) e RMSFtric (p <.001) no músculo tríceps braquial (antagonista). A adição de vibrações locais no treinamento contra ­ resistência, induziu um aumento da força máxima, força explosiva e uma redução da capacidade de sustentar a produção de força.