For strong pack-carrying shoulders, try the dolphin pose – which also provides an excellent stretch

1. Start on your hands and knees.
2. Bring your elbows to the floor under your shoulders.
3. Clasp your hands together. Point both pinky fingers straight ahead.
4. Don’t move your arms, but try squeezing your elbows towards each other as if you’re giving someone a hug with just your elbows. Keep the muscle action of squeezing. This protects and strengthens your shoulders.
5. If it feels ok for your shoulders, try lifting your knees off the ground and lifting your hips up.
6. Relax your neck and head. Just let your hand hang.
7. Stay here for a few breaths. Then bring your knees down, release your hands and take a few breaths before sitting up.
8. To counter this pose, try clasping your hands behind your back, or even just grabbing your wrists, or elbows behind your back.
9. Repeat this pose a few times to build strength. Over time, aim to increase the length of time you can comfortably hold the pose.