If you're new to lifting, doing big lifts like presses and squats is just as good for getting stronger as doing those plus extra isolated arm exercises.
Scientific Claim
In untrained young women, 8 weeks of multijoint resistance training alone or combined with single-joint exercises leads to similar significant improvements in muscle strength for elbow extension, elbow flexion, and knee extension, with no meaningful difference between the two approaches.
Original Statement
“Increases in 10RM load in elbow extension (28.2% for MJ and 28.0% for MJ + SJ), elbow flexion (29.8% for MJ and 28.7% for MJ + SJ), and knee extension (26.92% for MJ and 23.86% for MJ + SJ) were all significant and not different between groups.”
Evidence Quality Assessment
Claim Status
overstated
Study Design Support
Design cannot support claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The abstract implies equivalence but does not confirm randomization or control for baseline differences. Therefore, 'leads to similar improvements' implies causation; only association can be claimed.
More Accurate Statement
“In untrained young women, 8 weeks of multijoint resistance training alone or combined with single-joint exercises is associated with similar improvements in muscle strength for elbow extension, elbow flexion, and knee extension.”
Evidence from Studies
Supporting (1)
Influence of Adding Single-Joint Exercise to a Multijoint Resistance Training Program in Untrained Young Women.
Both groups of women got just as strong in their arms and legs after 8 weeks of lifting weights, whether they did only compound exercises or added isolated ones too — so adding extra exercises didn’t help them get stronger faster.