According to the book, "Exploring the Biological Contributions to Human Health: Does Sex Matter?", there are significant differences in cardiovascular performance between males and females. For instance, women are less likely to experience cardiovascular events during exercise due to the protective effect of estrogen. Yet, on the other hand, woman are at a disadvantage when it comes to oxygen-carrying capacity, cardiac output and maximum heart rate.
Oxygen-Carrying Capacity in Females
As a female athlete, your oxygen-carrying capacity is lower than a male's, according to the book, "DeLee and Drez's Orthopaedic Sports Medicine." This is due to the naturally lower hemoglobin levels in your blood. Hemoglobin is the metalloprotein that carries oxygen molecules in your bloodstream. When it is lower, then your ability to carry oxygen to your muscles is lower compared to a man's. In addition, females on average have 30 percent less cardiac output than their male counterparts. So in order to compensate for this, you need to increase your heart rate to produce male equivalence results.
Maximum Heart Rate in Female Athletes
In order to calculate your exercise target heart rate, you must correctly calculate your maximum heart rate, according to "Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine." Your target is 80 percent of your maximum heart rate.
"Braunwald's Heart Disease" explains that the standard formula to determine maximum heart rate is based on the expected heart rates of men during exercise. It overestimates the female's maximum. It calculates the maximum by subtracting your age in years from 220, or HR = 220 - Age.
According to author, Dr. Robert Bonow, female athletes can accurately determine their maximum exercise heart rate by multiplying their age in years by 0.88, then subtract it from 206, or Female HR = 206 - 0.88 x age.
Pregnancy and Cardiovascular Performance
When you are pregnant, your cardiovascular performance changes in your first trimester to meet the demands of your growing uterus and the placenta, according to "Sport Science Perspectives for Women."
In "Seminars in Perinatology," Dr. James Pivarnik explains that your cardiac output increases during pregnancy, while your systemic blood flow shunts to your uterus.
Menopause and Exercise
"DeLee and Drez's Orthopaedic Sports Medicine" states that postmenopausal women lose the protective effects of estrogen on cardiovascular health. Yet, exercise effectively increases your cardiovascular health and heart contractility during your postmenopausal years.
After menopause, moderately-intense activity still decreases blood pressure and carotid artery stiffness. So, with a health care provider's guidance, you can participate in vigorous exercise well into your golden years.
References
- "Delee & Drez's Orthopaedic Sports Medicine" 3rd ed.; Jesse DeLee, M.D., David Drez Jr., M.D., & Mark Miller, M.D.; 2009
- "Exploring the Biological Contributions to Human Health: Does Sex Matter?"; Theresa Wizemann and Mary-Lou Pardue; 2001
- "Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine" 9th ed.; Robert Bonow, M.D.; 2011
- "Exercise and Aging"; Exercise for the Elderly: What Are the Benefits and How Do We Get Started; Robert Serfass, Ph.D.; 981
- "Sport Science Perspectives for Women"; Jaccqueline Puhl, Harmon Brown, & Robert Voy; 1988
- "Seminars in Perinatology"; Cardiovascular Responses to Aerobic Exercise During Pregnancy and Postpartum; James Pivarnik, M.D.; 1996
