The quads are large and powerful because they move the largest bone in your body, your femur. They also stabilize and extend your knee. Runners, all the more reason to give them some love. Practice deep lunges to access this area with anjaneyasana, as well front body opening back bends like dhanurasana (bow pose). A quick and accessible sequence to stretch these bad boys so you can go (run) the distance. Props Needed: A block.