It is possible (and a must!) to get a good sports bra that supports and controls motion without too much constriction for a size 42G.  But there is also no need to chose physical activities that have a "bounce".  Why run and jump when you can walk, bike, skate, ski, swim, dance, strength-train with weights, use non-impact machines like the rower, and do yoga, Pilates and martial arts instead?  Athletes come in all shapes and sizes.