Start in forward bend pose however, put your hands on the ground (shoulder length apart) and place your feet beside the exterior of each hand. (fitbodyhq.com)
You can also try seated forward fold, spread - legged standing forward bend, tree pose, and bound angle pose. (mindbodygreen.com)
The classic seated forward bend with legs straight out in front is a wonderful calf stretch and specifically targets the back leg muscles. (fitbodyhq.com)