I get pretty sore from jumping if I'm not jumping regularly. I think you have to get your body into "Jumping Shape." I don't skydive for a living but I'd guess those who do jump everyday their bodies get use to the jump activity. I attribute some soreness to the arching and the openings, but a fair amount of it can be blamed on my poor posture while I'm packing and just being out of shape. Student canopies don't always open the softest as in your case probably. I'd have to agree, Ibuprofen and beer Is the way to go!!
JM