Difference in One-Repetition Maximum and Electromyography between the Dominant and Non-Dominant Arms and Their Relationship to Exercise Onset: An Experimental Study of the Biceps Brachii Muscle

The existence of differences between the two arms in terms of strength is considered an original and contemporary issue together, due to the different scientific opinions about the value of the difference, its determinants and causes, and the extent of the impact of the weight-bearing technique on it.

This study aimed to identify the difference in the One-Repetition Maximum (1RM) and Electromyography (EMG) between the dominant and non-dominant arms based on the arm used to start the exercise.

The study sample consisted of 16 healthy male beginners in weightlifting and resistance sports with the following averages: (Age = 19.6 years, BMI = 21.65 kg/m2, Mass = 66.23 kg, and Muscle Mass = 21.46). Special tests were performed to determine the EMG and apply the (EPLEYS Equation) to calculate the 1RM and perform the exercise One Dumbbell - Single Arm Bicep Curl.

The study's results showed a difference in 1RM between the dominant and non-dominant arms regardless of which arm started the exercise, but there were no differences in EMG between the dominant and non-dominant arms.

  The study recommended accustoming individuals to use both arms and performing special harmonic exercises in the non-important arm to compensate for the difference in strength between both arms, due to the importance of muscular strength in our daily lives as one of the elements of physical fitness related to health.