Seated forward bend (Paschimottanasana) or Standing forward bend (Uttanasana) will relieve mild depression and stress. It will calm your brain and stimulate your kidneys and liver. It will also strengthen your knees and stretch your hips, calves and hamstring.
Seated forward bend (Paschimottanasana) start by sitting down with your feet extended in front of you. Now bend forward until your stomach touches your thighs. You may not be able to get there and that is alright, go as far as your body will allow (encourage yourself in your mind's eye to release any unwanted tension, or uptightness. The more you do this and allow the body to open the closer you will get your chest to your thighs. Hold your feet with your hands for 30 seconds.
Standing forward bend (Uttanasana) stand straight and allow yourself to bend forward. Stretch your body allowing yourself to touch your palms on the ground. Straighten your legs for deeper stretch and hold this pose for three to four deep breaths.