The Study
Non-uniform excitation of pectoralis major induced by changes in bench press inclination leads to uneven variations in the cross-sectional area measured by panoramic ultrasonography
This study is like taking a picture of what happens to muscles when people do different types of bench press exercises. It shows that when you change the angle of the bench, different parts of the chest muscle work harder. But because researchers didn't randomly assign people to different groups and didn't have a control group, we can't say for sure that the exercise angle actually CAUSED those muscle changes. We can only say the two things seemed to happen together.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Researchers used special cameras (ultrasound) and muscle activity sensors to look at two parts of the chest muscle (pectoralis major) while people did bench press at different angles. They wanted to see if tilting the bench changes which part of the chest muscle works harder.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 526 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes - this matters for people who want to target specific parts of their chest.
- 2If you want to build your upper chest, incline bench press may be better.
- 3If you want to focus on the middle/lower chest, flat bench press may be better.
- 413 men did flat and 45° inclined bench press.
- 5When the bench was tilted up at 45°, the upper chest (clavicular head) worked harder and got bigger right after exercise.
- 6When the bench was flat, the middle/lower chest (sternocostal head) worked harder and got bigger.
- 7These differences were statistically significant (P < 0.001 for activation, P = 0.046 for cross-sectional area after flat press).
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of Electromyography and Kinesiology
Year
2022
Authors
José Carlos dos Santos Albarello, Hélio V. Cabral, Bruno Felipe Mendonça Leitão, Gustavo Henrique Halmenschlager, Tea Lulic-Kuryllo, Thiago Torres da Matta
Related Content
Claims (5)
Scientists can use two tools together - one that measures muscle electrical activity and another that takes wide ultrasound pictures - to see how specific parts of the chest muscle change right after working out.
When you do bench press on an incline, the upper part of your chest works harder. But when you do flat bench press, the middle-lower part of your chest works harder instead. Scientists measured this using muscle activity recordings.
When people do bench press on an inclined bench, the upper part of their chest muscle swells more than the lower part, showing different responses within the same muscle.
When people do flat bench press, the lower part of their chest muscle grows more than the upper part - and this is the opposite of what happens when they do incline bench press.
When you change the angle of the bench press, it might make the different parts of your chest muscle work in uneven ways, potentially causing one part to activate differently than the other.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.