A Comparative Electromyographical Investigation of Muscle Utilization Patterns Using Various Hand Positions During the Lat Pull-down

Abstract

This study aimed at investigating the effects of different hand positions on the electromyographic (EMG) activity of shoulder muscles during the performance of the lat pull-down exercise. Ten healthy men performed 3 repetitions of the lat pull-down exercise using their experimentally determined 10RM (repetition maximum) weight. Four different common variations of the lat pull-down were used: close grip (CG), supinated grip (SG), wide grip anterior (WGA), and wide grip posterior (WGP). Normalized root mean square of the EMG (NrmsEMG) activity for the right posterior deltoid (PD), latissimus dorsi (LD), pectoralis major (PM), teres major (TM), and long head of the triceps (TLH) were recorded using surface electrodes and normalized using maximum voluntary contractions. Repeated measures analysis of variance for each muscle detected statistical differences (p < 0.05) in myoelectric activity among hand positions during both the concentric and eccentric phases of the exercise. During the concentric phase, NrmsEMG results for the LD included WGA > WGP, SG, CG. For the TLH: WGA > WGP, SG, CG and WGP > CG, SG. For the PD: CG, WGA, SG > WGP. For the PM: CG, WGA, SG > WGP. During the eccentric phase, the LD produced the following patterns: WGA > WGP, SG, CG and WGP > CG. The TLH pattern showed WGA > SG and CG. For the PD: CG > WGA, WGP. The results indicate that changes in handgrip position affect the activities of specific muscles during the lat pull-down movement. Also, performance of the lat pull-down exercise using the WGA hand position produces greater muscle activity in the LD than any other hand position during both the concentric or eccentric phases of the movement.

Estimativa das forças na articulação tíbio-femoral no exercício de extensão dos joelhos em cadeia cinética aberta realizado em máquina de musculação

“…O modelo biomecânico adotado no presente estudo (2D) baseou-se na equação de equilíbrio de torques a partir da análise de diagramas de corpo livre dos segmentos avaliados 10,15 . É crescente o número de estudos acerca da biomecânica do treinamento de força, no entanto, percebe-se que a maioria se detém em análises da atividade muscular em diferentes exercícios 16,17 . Alguns estudos foram realizados com o intuito de melhor compreender a biomecânica do exercício de extensão dos joelhos em CCA 5,[9][10][11] , no entanto, a metodologia destes não se aplica perfeitamente quando este é realizado em uma máquina de musculação.…”

Effect of Postactivation Potentiation on Fifty-Meter Freestyle in National Swimmers

“…Day 1 of testing included calculation of the 3RM PU, the effort was preceded by a warm-up of the upper body that involved pulling actions with elastic bands and 2 sets of 4 repetitions of the assisted PU. The PUs were performed with a pronated forearm grip on a standard horizontal bar with the hands placed 10 to 15cm wider than shoulder width apart (23). The 3RM was determined by adding the athlete's body weight to a vest's additional weight that was worn during the 3RM PU test.…”

Pulling Exercises for Strength Training and Rehabilitation: Movements and Loading Conditions

“…To our knowledge, analyses of pulley exercises for the back have mainly focused on maximal power output or electromyographic (EMG) activity [25][26][27][28]. For instance, the global muscle contraction under the different activity stimuli was studied, and it was revealed that all selected exercises activate the latissimus dorsi and trapezius, but to varying degrees [29].…”