Be careful about practicing punching with weights -- I am not saying don't do it, but I am saying be careful and investigate the recommendations from people who know. Some trainers recommend against it as being dangerous to your joints etc.

Also, consider Shadow Sparring where you are fighting normally but hitting VERY lightly. Hitting just enough to let each other know you are there. If you do this enough you will definitely find that you "get hit" occasionally and as long as you keep it to mostly very light that won't be too much for most people. (Work only with guys you trust to play fairly close to the rules that you agree upon.)

Wear a mouthpiece (and headgear if you wish). Sometimes a punch will otherwise bust a lip etc if you don't wear the mouthpiece. Don't hit so hard you NEED the headguard, but don't hesitate to use if if that seems the safest course.

If you are getting angry or frightened you are going too hard -- or working with the wrong partner. Talk to each other, slow down, or find someone else for THIS exercise.

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HerbM