Dolphin Pose
This pose is excellent for opening up the chest, shoulders and the hamstrings. It also mirrors the proper upper body alignment for cyclists.
Start on your hands and knees, with your knees directly beneath the hips and hands slightly in front of your shoulders. Exhale and tuck your toes under, pressing your tailbone toward the sky. Keep your knees slightly bent to start. Press your heels toward the ground. It is okay if they don't reach it. Lower down onto your forearms, with your elbows directly beneath your shoulders. Broaden your shoulder blades away from each other. Breathe deeply and hold for one to two minutes.
Setu Bandha Sarvangasana (Bridge Pose)
This pose is a great counter-pose for your upper body positioning while on your bike. It will open up the front of your body and strengthen your spine.
Start on your back with your knees bent. Position your feet about six inches away from your hips. Make sure that your feet are pointing straight ahead. Inhale and press your feet into the floor and lift your pelvis up as high as you can comfortably. Slide your shoulders underneath you, clasping the hands. Breathe evenly. Hold for 30 to 60 seconds. Slowly lower down, one vertebra at a time.