Massage
Take a hands-on approach to proprioception. During massage the misunderstood sense proprioception is being developed in both the participants. As the masseur varies the "amount" of muscle they use they are relying on proprioception, while those who receive the massage appreciate those differences via their own proprioceptive sense. Different textures (or vibration) make massage easily stimulating, but the best tool is a hand, the best technique patience, and the best duration longer.
