Background: Impaired muscle performance, muscle weakness and atrophy, even sarcopenia (reduced muscle mass and strength) can be caused by injury, disease, immobilization, disuse, and inactivity. Resistance training is an appropriate therapeutic intervention to increase integrated muscle power, strength, and endurance during functional movement, to reduce the risk of injury or re-injury, and to improve physical performance. Objective: To compare the effectiveness of free weights (dumbbells) and elastic resistance bands in increasing the biceps brachii muscle strength on untrained subjects during four weeks of training. Methods: The study was conducted from February to March 2021. Twenty-four men with low and moderate activity levels were recruited and randomized into the dumbbell group (DB) and the elastic resistance bands (ERB) group. Each group was given a biceps brachii muscle strengthening exercise program for 4 weeks. Maximum voluntary isometric contraction (MVIC) of biceps brachii muscle was collected before and after treatment. Results: There was a significant difference in the MVIC value before and after 4 weeks of exercise in the DB group (right p-value 0.002 and left p-value 0.003) and the ERB group (right p-value 0.000 and left p-value 0.001), there was no difference significant difference in MVIC of the right and left biceps brachii muscles before and after 4 weeks of exercise between the two groups (right p-value 0.453 and left 0.714). Conclusion: Free weights and elastic resistance bands show the same effect in increasing MVIC on untrained subjects

Muscle strengthening exercises; elastic resistance bands; dumbbells; maximum voluntary isometric contraction (MVIC); Indonesia