The Claim
In untrained young men, adding single-joint exercises to a multi-joint resistance-training program for 10 weeks does not result in greater increases in elbow flexor muscle thickness or peak torque than multi-joint exercises alone.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
For untrained young men, adding isolated arm exercises like bicep curls to a workout routine that already includes compound movements like bench presses and rows does not lead to bigger arm muscles or stronger elbow flexion after 10 weeks of training.
See the scientific wording
Adding single-joint exercises to a multi-joint resistance-training program for 10 weeks in untrained young men does not result in greater increases in elbow flexor muscle thickness or peak torque compared to multi-joint exercises alone, suggesting that single-joint movements provide no additional benefit for strength or hypertrophy gains in this population.
When untrained men do compound exercises like push-ups and pull-downs, their arm muscles get stretched and pulled hard enough to trigger all the growth and strength signals they can handle; adding isolated arm curls doesn’t push those signals any higher, so the arms don’t get bigger or stronger than they already did from the compound moves alone (10.1139/apnm-2012-0176).
What the research says
1 studyFor guys just starting weight training, doing arm curls and triceps extensions on top of push-ups and pull-downs didn’t make their arms any bigger or stronger than just doing the push-ups and pull-downs alone.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.