Upper back muscles
23 Shoulder and Back Exercises You Can Do At Home
Lie on your left side, your right foot stacked over your left foot. Using your left forearm, lift your upper body off the floor so your body is in one straight line. Your left elbow should be stacked below your left shoulder, your left forearm straight in front of your body. Raise your right arm toward the sky. Keep your core tight, and don't let your hips drop. Repeat on the other side.