Mannarino, P, Matta, T, Lima, J, Simão, R, and Freitas de Salles, B. 
Single-Joint Exercise Results in Higher Hypertrophy of Elbow Flexors Than 
Multijoint Exercise. J Strength Cond Res 35(10): 2677-2681, 2021-Recent data 
suggest that single-joint exercises are unnecessary to maximize the resistance 
training (RT) results in novice to advanced individuals. However, the present 
literature is still inconsistent on this topic and controversy arises. The aim 
of this study was to compare the effects of the unilateral dumbbell row (DR) 
(multiple-joint) vs. unilateral biceps curl (BC) (single-joint) exercises on 
strength and elbow flexors muscle thickness (MT). Ten untrained men were 
assigned to an 8-week RT program for elbow flexors, one arm performing DR and 
the other performing BC in a within-subject design. After a familiarization, 
pretraining MT was measured using an ultrasound (US) technique, and strength was 
tested using 10 repetition maximum (10RM) tests. After pretesting, 8 weeks of RT 
(4-6 sets, 8-12 repetitions to concentric failure, 2 sessions per week) was 
performed. Post-testing was conducted in the same order as pretesting 48 and 72 
hours after the last session. Single-joint BC exercise resulted in higher 
hypertrophy of elbow flexors (11.06%) than the DR (5.16%) multijoint exercise 
after 8 weeks of RT (p = 0.009). The 10RM improvement was higher for DR in 
DR-trained arm, whereas 10RM for BC was higher in BC-trained arm. The 
single-joint exercise resulted in higher hypertrophy of the elbow flexors than 
multijoint exercise after 8 weeks of RT, whereas strength improvements were 
greater in accordance with specificity of RT exercise. Therefore, in RT 
prescription for elbow flexors hypertrophy, single-joint exercises such as BC 
should be emphasized.