To prevent breast tenderness, discomfort, or pain (mastalgia), follow these tips:
Wear a sports bra during exercise. A sports bra may prevent breast discomfort, pain, and injury during exercise or sports. It is important that the sports bra fit properly. It should keep the breasts almost motionless and allow them to move together with the chest, not separately. Be sure to replace your sports bra as the material stretches and become less supportive. A sports bra may need to be replaced every 6 months if it is used regularly.
Limit your salt intake. High salt intake may cause fluid retention. Fluid retention may be the cause of premenstrual breast tenderness.
To prevent nipple irritation during exercise:
Cover your nipple with a small bandage or a dab of petroleum jelly before you exercise.
Wear a sports bra that fits you properly. Avoid sports bras that are lined with cotton.