Last year I was working w/a buddy on blocking drills. We would assume a "horse stance" face-to-face. Measure the distance with extended arm so we could kind of avoid clocking each other. Then one of us would throw 10 punches to a target area. (10 each hand for total of 20). Targets are head, stomach, groin. The receiver would block. The point is not to hit your partner, the point is to provide an attack that your partner can practice blocking. And a good partner will block hard. You both gain. Overall intention was to improve muscle memory, eliminate "thinking" in the basic moves and to condition arms and wrists. This was excellent practice. Then we would do the drills up and down the floor. Adding movement can lessen the discomfort. Luck.