Hair growth is a natural three-phase process; growth is never caused by exercise. The hair growth process can be interrupted by mental and physical health problems, resulting in hair loss, though. Cardio can’t make your hair grow, but regular cardio exercise can improve your health and mood. So while it can't make it come back, cardio may be able to reduce or eliminate some of the health problems that lead to hair loss.
How Hair Grows
Hair grows in a repeating cycle of three phases called Anagen, Catagen and Telogen. In the first phase (Anagen), a new hair shaft is formed, is nourished by blood and grows, which takes from two to eight years. In the next phase, which lasts for two to four weeks, the hair is pushed away from the blood supply and stops growing. In the final resting phase, which lasts two to four months, the hair is no longer nourished but doesn’t fall out. After the final phase, the hair-growth cycle is complete, and the first phase starts over again, pushing out the old hair shaft and forming a new one. In this process, 50 to 100 hairs will be lost each day so new hair can grow.
Causes of Hair Loss
Hair is lost temporarily or permanently when the hair growth cycle ends, but a new hair shaft isn’t formed. Stress, illness, hormonal changes, poor nutrition and medications are some of the things that can disrupt the growth cycle and cause hair loss. Some people experience hair loss about three months after the start of a stressful period of their lives. If the stress continues, the hair loss will continue about three months more, or longer for some people, after things calm down again. Some medications that treat heart problems, high blood pressure and depression can cause temporary hair loss. Both men and women can experience hair loss caused by hormonal changes related to aging.
Hair Health and Happiness
Lower your chances of experiencing hair loss caused by stress and physical health problems by keeping both your mind and body in the best possible health. By releasing endorphins and other feel-good hormones, cardio can relieve stress and make you happier, according to Psychology Today. For good physical health, the American Heart Association recommends at least 150 minutes of moderate cardio exercise or at least 75 minutes of vigorous cardio exercise to maintain a healthy heart and veins.
Food for Healthy Hair
Low iron and a low-protein diet can also cause hair loss. Cardio depletes iron supplies, and young female athletes and vegetarians are at the greatest risk of developing anemia. Iron-rich foods -- including red meat, fish, poultry, spinach and beans -- can prevent low iron levels caused by exercise, sometimes called sports anemia. Avoid hair loss from protein deficiency with a diet including at least 46 grams of protein each day for women and 56 grams for men.