When you do preacher curls for 10 weeks, your strength in the middle and fully bent positions gets better no matter if you use a cable or barbell — the resistance pattern doesn’t make a difference there.
Scientific Claim
In young, untrained adults, 10 weeks of preacher curl training improves elbow flexion strength at 60° and 100° of elbow flexion regardless of whether peak torque is applied at short or long muscle lengths, with no significant difference between cable and barbell methods, suggesting that strength gains at mid- and end-range positions are not torque-position dependent.
Original Statement
“For elbow flexion peak torque at 60°, significant increases were observed for both CAB (pre = 32 ± 12 Nm, post = 40 ± 12 Nm; ES = 0.73; +27%) and BAR (pre = 30 ± 12 Nm, post = 39 ± 14 Nm; ES = 0.79; +32%), without significant difference between them (p = 0.874). For elbow flexion peak torque at 100°, significant increases were observed for both CAB (pre = 31 ± 11 Nm, post = 36 ± 11 Nm; ES = 0.54; +17%) and BAR (pre = 26 ± 9 Nm, post = 32 ± 8 Nm; ES = 0.52; +20%), without significant difference between them (p = 0.728).”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
The RCT design with precise isokinetic testing and non-significant p-values (p>0.7) supports definitive claims of equivalence for these specific angles in this population.
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Systematic Review & Meta-AnalysisLevel 1aWhether training with variable torque profiles consistently leads to non-specific strength gains across joint angles in dynamic exercises.
Whether training with variable torque profiles consistently leads to non-specific strength gains across joint angles in dynamic exercises.
What This Would Prove
Whether training with variable torque profiles consistently leads to non-specific strength gains across joint angles in dynamic exercises.
Ideal Study Design
A meta-analysis of RCTs comparing exercises with peak torque at short vs. long muscle lengths, measuring isokinetic torque at 3+ joint angles, with standardized training protocols and reporting of angle-specific effect sizes across populations.
Limitation: Cannot determine neural vs. structural mechanisms behind non-specific gains.
Randomized Controlled TrialLevel 1bIn EvidenceWhether strength gains at non-trained angles are due to neural adaptations or cross-training effects from other exercises.
Whether strength gains at non-trained angles are due to neural adaptations or cross-training effects from other exercises.
What This Would Prove
Whether strength gains at non-trained angles are due to neural adaptations or cross-training effects from other exercises.
Ideal Study Design
A double-blind RCT with 80 young adults randomized to cable or barbell preacher curls, with all other exercises controlled, measuring torque at 20°, 60°, 100°, EMG, and muscle thickness pre/post 10 weeks.
Limitation: Still limited to untrained individuals; cannot isolate effects of other exercises in real-world settings.
Prospective Cohort StudyLevel 2bWhether the non-specific strength gains persist and transfer to real-world tasks over time.
Whether the non-specific strength gains persist and transfer to real-world tasks over time.
What This Would Prove
Whether the non-specific strength gains persist and transfer to real-world tasks over time.
Ideal Study Design
A 2-year cohort tracking 100 resistance-trained adults using either cable or barbell preacher curls, measuring functional strength (e.g., dumbbell curl 1RM) and joint-specific torque at multiple angles annually.
Limitation: Cannot control for confounding variables like diet, sleep, or other training.
Evidence from Studies
Supporting (1)
Placing Greater Torque at Shorter or Longer Muscle Lengths? Effects of Cable vs. Barbell Preacher Curl Training on Muscular Strength and Hypertrophy in Young Adults
Both cable and barbell preacher curls made people stronger at bending their elbows halfway and all the way, no matter which method they used — so the type of equipment didn’t matter for those positions.