Punching bag routine, anyone have a good one?

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1. work on rounds
2. 2-5 rounds on speed bag
3. I do 2 rounds of each of the following, right handed and left handed
4. lead hand only - basically jab, or jab hook
5. jab cross only
6. everything you know
7. uppercuts and hooks only
8. I do about the same amount of time on non-fists - elbows, slaps, knees and kicks, but if you are boxing, stick to boxing.

Exactly. You can do those workouts as shadowboxing or with a partner holding pads as well.

Gym trainer or a boxing coach?

I'm not a big speed bag guy, but I enjoy the heavy bag. Strikes are all well and good, but you can't forget your footwork (strike angles, moving in and out of range), body/head movement, and keeping your hands up.

Outside of that, work your combos, make sure to change elevations, and pretend like the bag is an actual opponent.