Mark Ottobre explains why your back won't grow: you're pulling with your arms instead of your shoulder blades. Move your scapula back and down first, keep your elbows straight, and you'll recruit more back muscles and make chin-ups feel easier.
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If we interlock hands, right, if I just use my arm, if you resist me, so just use a little bit of force to resist me, right? So if I pull you, you resist me, right? Yeah. So if I'm here, see my scap, I'm forward, you can feel the pressure, right? If I put a bit more on it, so really resist me, right? So I'm just using my bicep, okay? Most people when they row, they row with just their arm. When you're doing this, if you think when you stretch, and the reason why I get you to start from there is because when we're here, what I want to see is The retraction, the depression. So if I do that, see this, I haven't bent my elbow. Yeah. My elbow is straight. So you should be able to go from here, generate force retracting and depressing. That's a whole movement in and of itself because there's 3 joints now moving instead of 1. So on that chin-up, the reason why I'm going to constantly say get here is so in this position you have more room for the joint to move to do that. So your chin-ups will feel easier. It's a higher skill, but you are recruiting more muscle as well and the joint is articulating.