🔥 Should you move your shoulders during a bicep curl?
✳This question seems to arise a lot, whether it is good to move your shoulders during a bicep curl. The idea is that since the biceps does perform shoulder flexion we should perform both actions at the same time to get the full benefit. Unfortunately that’s not how it works; muscles have a hard time performing two actions at the same time when they cross a joint. That is where active and passive insufficiency comes from, also think about it if you want to pull something and the place you’re holding on to starts moving it’s going to be a lot harder to do your job.
✳Even if we dive into the research, some articles show us a greater increase in muscle activity during shoulder flexion HOWEVER during an isometric contraction, which makes sense the bicep is holding the shoulder and elbow into flexion but not moving. Looking at comparative exercises, like the standing bicep curl and a preacher curl the preacher curl has less muscles activation compared to the standing because of active insufficiency. So during static hold it makes sense, but once we introduce motion to the joints things change.
✳ Second thing to consider is that once we add shoulder flexion stronger shoulder flexors will begin to work like the anterior deltoid. This adds extra momentum taking away from the tension that would otherwise go on the biceps. And lastly with shoulder flexion we change the moment arm of the elbow joint again decreasing the resistance the bicep must work for.
✳ A great bicep exercise that I would recommend is the incline bench curl; I was never a fan of it till recently because I found out its usefulness. Biceps can get over trained and tight which can lead to problems in the future. Inclines curls can help with that, since the shoulder is in extension the biceps is in an elongated position, training eccentrically during this exercise can help lengthen the fibers and decrease tightness over time.