Physical Therapy Korea (May 2022)

Comparison of Muscle Activities in Upper Extremity Muscles During the Knee-flexed and Standard Push-ups With Different Hand Shape

  • Sang-jin Jeong,
  • Ji-hye Kim,
  • Hae-jin Kong,
  • Min-ji Cho,
  • Hyeon-ji Baek,
  • Su-jin Kim

DOI
https://doi.org/10.12674/ptk.2022.29.2.117
Journal volume & issue
Vol. 29, no. 2
pp. 117 – 123

Abstract

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Background: Push-up are effective exercises for shoulder stability. Previous studies have documented the effects of support plane and hand position and width on muscle activities during a push-up.Objects: This study aimed to investigate the changes in muscle activities in the upper extrem-ity when performing the standard and the knee-flexed push-up with different hand shapes.Methods: A total of twenty-six healthy males participated in this study. Three different hand shapes (finger abduction, finger adduction, and fists) and two types of push-up posture (stan-dard and knee-flexed push-up) were set as the independent variables. Electrograms were used to measure the muscle activity of the upper trapezius (UT), triceps brachii (TB), pectoralis major (PM), and serratus anterior (SA). Each participant performed the randomly assigned push-up to the sound of the metronome. The mixed-effect linear regression model was used to detect the changes in muscle activities after changing the hand shape and push-up posture. Statisti-cal significance was set at α = 0.05.Results: The UT muscle activity was statistically significantly higher when performing push-up with fists than finger abduction (p = 0.035) or finger adduction (p = 0.044). During the stan-dard push-up, the muscle activity in all muscles was that the push-up with fists showed the highest muscle activity compared to the finger abduction (p < 0.01) and finger adduction (p < 0.01). Regardless of the shape of the hand, UT had the lowest muscle activity compared to other muscles (p < 0.001). In contrast, the SA muscle had the highest muscle activity among four muscles during the standard push-up.Conclusion: Based on the results of this study, we suggest hand shape is related to the difficulty level of push-up either in the standard or the knee-flexed push-up, especially in the push-up with fists. In addition, knee push-up can be recommended as shoulder muscle-strengthening exercises for individuals with low shoulder muscle strength.

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