Single-arm hammer curl. Hold a dumbbell in each hand and turn your palms towards your body. Hug the elbows in toward your waist. Curl up the right arm first, then lower it down.

The hand, developed at Switzerland’s EPFL, can detach from an arm, crawl around on its own, grab small objects, and bring them back before reattaching itself.

Stand with feet hip-width apart, holding a dumbbell in each hand. Glue elbows to sides, and hold forearms out at a 45-degree angle away from body. Without moving upper arms, bend elbows and curl ...

With your left hand, gently pull back the fingers of your right hand. Hold this stretch for at least 3 deep breaths. Let your right wrist go limp, the fingers pointing down.