👊🙏

Yes!

You’re correct. It’s not truly zero, mainly because this is a true “closed chain” exercise. (Tying to be concise on a KZfaq video always excludes some nuance, I should have said “near zero” or “little/less torque”

@@HypertrophyCoach yeah man, I really appreciate the mechanics you go over in your videos, this stuff is going through my head constantly at the gym. Thinking about it more: imagine you had no muscles driving your shoulder, no delts, no pecs, just a simple hinge. With your hands fixed at the bars, the movement could in theory be driven 100% by the triceps. Conversely imagine you had no triceps, just pecs/delts/etc. With your hands fixed, you could theoretically drive the movement 100% from the moment exerted at the shoulder. Not the case with dumbbells of course. With perfect mind muscle connection I suppose you could in theory shut down either muscle group and achieve that zero force case you describe - at the triceps OR at the shoulder.

I'm still confused about the greater shear force from flys vs presses. I've certainly experienced greater shoulder stress from heavy flys it but mechanically I don't get it. The only thing I can think of is the angle between the femur and the torso - flys are typically done with about the same femoral angle as a guillotine press, which yeah, has a bad rep as a shoulder killer.

Sadhu Cat yes. That’s exactly what “closed-chain” implies, the same reason you said you couldn’t with a free weight. The only caveat is our joints aren’t held together with “pins” at the axis, muscle force could never really be zero as they are needed for joint integrity

Sadhu Cat it’s only less for the same amount of torque. The ruff equation for sheer is torque minus load. Considering you can achieve the same torque of a fly that you could with a press, with a far lighter DB (because of the larger moment arm)...if you do the math, it will create more sheer

Hassan Bilal nautilus