One of the best things you can do for your legs and body is this! And all you need is a wall!
Super simple, just get your backside nice and close to the wall and put your legs up it. If your legs are straight up you can get a deep hamstring stretch, make sure you pull your toes towards you to increase it further or even use a belt or band to increase the pressure.
Spreading your legs against the wall, aside from being really relaxing, helps to stretch your adductors, hamstrings and calf muscles.
Take 5 minutes every day to stretch, your body will thank you immensely. Share this post with a friend with a bad back who could do more lower body stretching.