Here are some simple Lat stretches (Latissimus Dorsi) for rehabilitation or general soreness.
The first stretch will be a prayer stretch on the ground. The best thing to do is get down on your knees, and reach forward with your arms on the ground as far as you can. Then sit back onto your feet. If you need a little more of a stretch, then take the arm on the side you want to stretch more and place it over on the opposite hand. Push out and over for a bigger stretch. Hold for 30 seconds and repeat 3 times.
Next, stand up next to something firm and stable on a wall like a bar. Grab onto the bar and lean backwards arching your back. Hold for 30 seconds and repeat 3 times leaning back further each time.
Finally, stand straight up; take the arm of the side you want to stretch and bring it straight over your head. Then lean to the side and push your arm up and over like you are pointing to the opposite side of the ceiling. Hold for 30 seconds and repeat on each side 3 times.