To help reduce injury risk- wrist pronators & supinators.
Rotator cuff and general strength for power

Rhodo's list above is a pretty good start. It'll also depend a bit on your exact technique - try taking some slo-mo videos of yourself from different angles without a shirt and see which muscles are firing and when.

If you want full power, you'll need to go for a full baseball pitch motion - start with hip pointing at the target(chest at 90 degrees or greater), lead with hips and keep chest closed(not rotated) as long as possible, then use that tension in your core to whip your chest and arm around. There's tons of pitching literature out there and almost all of it applies exactly as-is to slinging, so be sure to check that out.

I've got a desk job, so I've found that I have trouble with my lower core a bit more than most people - I have to work on my hip flexors regularly(for the leg lift/rotation at the very beginning of the throw) and stretch my lower back/hips(glutes, psoas, lower QL) to keep them loose. From that perspective you have to keep in mind maintaining your existing power by not losing mobility in addition to strength training to increase your maximum.

I've noticed that I struggle to increase power by slinging alone. Maybe it would come eventually, but I think you'll have a much better time with traditional strength training (weights, bands, etc).

I've never had much of an upper body(but plenty of core/lower body from hiking), so I've found that upper body workouts benefit my power the most. I've observed a noticeable increase in power when I focus on my biceps and chest, but again I'm not sure if that's due to my build naturally lacking upper body or what. You can't go wrong if you work on all the major upper body groups - chest, biceps,triceps, shoulders. But be sure that's in concert with core and upper legs or you might end up with a weird imbalance.

I agree with eric….at least for me, powerful slinging mimics my old baseball pitching motion.

So baseball workouts would seem logical.

Attached is video clip showing sling motion similar to throwing by hand.

IronGoober wrote on Oct 8^th, 2026 at 11:15pm:


Yep. I add a few sets of pronations & supinations at the end of most of my workouts. I 3D printed a one sided dumbell handle (PETG-GF), but a 4kg sledgehammer is maybe a more accessable option. Increasing the distance between your hand and the hammer head increases the difficulty