Targets: shoulders + back + lats + coreFacing the floor, place your left hand and knee on an exercise ball. Holding an 8-pound dumbbell in your right hand like you would a bike handlebar, pull the dumbbell to your armpit, twisting your hand into an ice-cream-eating position. Do 12—15 reps. Repeat on the opposite side. For week three, keep your left hand on the ball; move your left foot to the floor 12 inches behind the ball, and extend your right leg behind you. Repeat the rows for three sets. "This one helps me with my skiercross starts, says Cline. For the rest of us, it'll enhance poling on the flats.
Muscle it up: Upside Down Ball Rows