: Shoulder work on the Bosu. This is really a "tennis serve" motion, but works the shoulder, core, and lower body (especially the calf)! 👊💪😰 #fit #getfit #stayfit #abs #TRX #biceps #core #cardio #fitcoteam #fitspiration #fitnessvideo #fitnessaddict #gym_videos #instafitness #Bosu #quickworkout #workoutsbyyou #trainhard #training_videos #trainingvideos #workout #workoutvideos #gymrat #HIIT #pushups #triceps #tabata #onesetapp