Mixed
Training elbow flexors in the initial range of motion (lengthened state, 0-68 degrees) promotes greater distal biceps hypertrophy and greater full-range 1RM strength gains compared to training in the final range of motion (shortened state, 68-135 degrees).
If you are doing bicep curls, try splitting your sets: do some reps starting from a fully extended arm (lengthened position) and others from a partially flexed position. This study suggests that prioritizing the lengthened position (starting from straight arms) may lead to better muscle growth in the lower part of the bicep and greater overall strength gains than prioritizing the shortened position (starting from a flexed arm).
The INITIALROM protocol displayed a greater CSA increase than FINALROM protocol at 70% of biceps length... Moreover, the INITIALROM protocol displayed a greater 1RM increase than FINALROM
Why this rating
Randomized controlled trial with within-subject design, adequate power, but short duration (8 weeks) and specific population (untrained women).
Source
Training in the Initial Range of Motion Promotes Greater Muscle Adaptations Than at Final in the Arm Curl
Gustavo Ferreira Pedrosa et al. · Sports · 2023
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