Breasts are made up of mammary glands and adipose (fat) tissue. You cannot target one specific body part with cardiovascular (cardio) exercise, so unfortunately there is no specific breast reducing cardio. However, you can reduce overall body fat with cardio exercises that keep your heart rate in your target zone over a period of time, such as running, swimming, team sports and cycling. As you start burning calories and fat, you will begin to see a reduction in breast size. Jump-start your fat loss by completing two cardio sessions a day. Do cardio exercises at least three to four times a week for continued results.
To find your target heart rate, subtract your age from 220. This will give your maximum heart rate. Multiply this by 0.50 and 0.85 to get your target heart rate. For example, if you are 20 years old, 220-20=200, which is your maximum heart rate. 200 x 0.50=100 and 200 x 0.85=170. So your target heart rate would be 100 to 170 beats per minute.
By strength-training your chest muscles, you can tone the area under your breasts. The breasts sit on top of pectoral muscles, which will flatten with the appropriate exercises to tone and tighten your chest. Use higher repetitions and lighter weights if your desired goal is a smaller breast size. Heavier weights will pack on muscle and size in your chest, giving you fuller and larger breasts.
Pec Deck Flys: Adjust the Pec Deck's seat and weight before starting. Sit against the padded seat with your feet on the ground. Reach back and grab the handles and rest your forearms against the pads. Pull the pads inward until they touch directly in front of your chest. Simultaneously return the pads to the starting position.
Bench Press: Lay down on the floor on an exercise mat or on a weight bench. Hold a barbell or dumbbells directly over your shoulders with your elbows bent. Press the weight straight into the air over your chest. Bend your elbows and return the weights to the original position.
Push-Ups: Perform a basic push-up on your hands and toes. Keep your back straight and lower your body by bending your elbows. Straighten your arms to complete one push-up. Try moving your hands further apart for different intensity.
Dips: Use a dip machine or parallel bars to perform dips. Hold on to the handles and straighten your arms, leaving your body hanging. Lean forward with your shoulders to work your chest muscles. Bend your arms, lower your body as far as you can go and push back up.