It's important to do stretches for chest tightness to improve your posture. Having tight chest and shoulder muscles causes the muscles to shorten and weaken. As a result, your shoulders become rounded and your head droops forward because your chest and shoulder muscles can't support a tall, straight back. Practicing yoga every day for 30 to 60 minutes, or at least once or twice a week, can help alleviate chest tightness, strengthen your muscles and build muscle memory for good posture.
Cat-Cow Pose is an appropriate stretch to start with to open your chest muscles and warm up your back muscles. Come into tabletop position with your shoulders stacked over your wrists and your hips over your knees. As you inhale, arch your back and drop your head gazing toward your navel. As you exhale, lower your belly, bring your chest forward and lift your head. Do about five Cat-Cow Poses.
Camel pose can be an intense chest muscle opener. Stand on your knees with your knees two fists-width apart. Place your hands on your lower back with your fingers pointing up or down. Pull your low belly in and point your tailbone down to protect your lower back. Bring your gaze across the ceiling toward the back of the room as you lift up through your chest and squeeze your shoulder blades together. Hold for five breaths, then ease your way out of the pose and sit on your heels for a few breaths to relax. To do the more advanced variation of Camel pose, place your hands on your heels instead of on your lower back.
Half Moon pose will stretch your pectoralis major and minor muscles and will also open your hips and build balance. Practice this pose with and without a wall. Start in a standing position. Place your right hand about 1.5 to 2 feet in front of your right foot. You can also place your hand on a yoga block to make the pose easier. Place your left hand on your left hip. Balance on your right foot and right hand as you lift your left leg and move toward stacked hips. Once your hips are stacked, reach your left arm high, moving toward stacked shoulders to stretch your chest. Gaze down, or if you're more advanced gaze up. Practice the pose using the wall and press your top hip and top shoulder against the wall to help stack your shoulder and hips. Hold the pose for at least five breaths.
Bridge pose will stretch your chest muscles while also building strength in your quadriceps. Lie on your back, knees bent and heels close to your sit bones. Lift your hips up toward the ceiling, create a fist with your hands and press your forearms down onto the ground. Lift your chest up toward the ceiling and slide your shoulders under your chest. Maintain a space between your chin and your chest to protect your neck. Hold for five breaths.