A: Both. Aerobic fitness may be more important in helping you prevent heart disease and colon cancer, but muscular fitness is superior in building strong bones and lowering your risk of low back pain.
You are not the only one who is confused about fitness and health. Physical fitness has been defined in different ways during the past 100 years. During the first half of the 20th century, fitness was equated with muscular strength, and is best represented with the story of Charles Atlas, the "97-lb weakling who became the World's Most Perfectly Developed Man" (1).
As a boy, Atlas was pale, thin, and physically abused by the larger kids in grade school. One day, while he was lying on the beach at Coney Island in New York with his girlfriend, a bully walked up and kicked sand in his face. His girlfriend walked away after the attack and never was seen again.
This incident became the catalyst that motivated Atlas to search for a way to build up his thin body. One day, he observed lions and other great cats at the zoo flexing their muscular bodies against the cage bars, thus keeping them strong with the resistance. This was a eureka moment for Atlas and led him to develop a calisthenics system, in which muscles were contracted and pulled, and called it dynamic tension. Using this new method, he transformed himself, and was victorious at the Most Perfectly Developed Man contest at Madison Square Garden in both 1921 and 1922. He decided to market his fitness workout, and it was adopted by millions of Americans during the mid-1900s.
For most adults at this time, fitness meant strong muscles, and Atlas was their fitness leader. He once displayed his power by pulling a 14,000-lb railroad freight car more than 100 feet, much to the delight of his followers. Up until the 1960s, he was a superstar, doing countless talk shows and appearing on the cover of virtually every magazine and newspaper. Some of his most noted pupils were Rocky Marciano, Robert Ripley, and Joe DiMaggio. Not only was Atlas' program hugely successful, but it also gained a great deal of respect. The American Medical Association approved of and enthusiastically endorsed his course in Dynamic Tension in 1950. Atlas died in 1972 at the age of 79 from heart failure.
The pendulum began to swing the other way toward a focus on aerobic fitness in the early 1970s. In 1967, Oregon track coach Bill Bowerman toured New Zealand and discovered the health benefits of long, slow running or jogging from Arthur Lydiard. He returned to America and wrote Jogging, igniting the first running boom in the United States, with his book eventually selling more than one million copies (2).
In 1968, Kenneth H. Cooper, M.D., a doctor for the Air Force, published his book, Aerobics (3), followed two years later by The New Aerobics (4). In these books, Dr. Cooper challenged Americans to take personal charge of their lifestyles and counter the epidemics of heart disease, obesity, and rising health-care costs by engaging in regular aerobic exercise. To Dr. Cooper, the best form of exercise was "aerobic," a word he coined to represent activities that stimulated the involvement of the heart and lungs. Stated Dr. Cooper, "the best exercises are running, swimming, cycling, walking, stationary running, handball, basketball, and squash, and in just about that order. Isometrics, weight lifting, and calisthenics, though good as far as they go, don't even make the list, despite the fact that most exercise books are based on one of these three, especially calisthenics."
Dr. Cooper's books provided the necessary theoretical fuel for an adult fitness revolution that soon zoomed across the country. Millions took up the aerobic challenge and began jogging, cycling, brisk walking, and swimming their ways to better health. Dr. Cooper's wife, Mildred, joined her husband in 1972 in writing Aerobics for Women (5). Within 9 years, these three books on aerobics sold more than 6 million copies and were translated into 15 foreign languages and into Braille. During the 1970s and 1980s, muscular fitness received little attention, and aerobic fitness was upheld as the superior method for achieving health.
The aerobic fitness movement spawned countless studies on the relationship between cardiorespiratory fitness and health (6-8). From this research, we learned that an aerobic program without a parallel focus on muscular fitness is not enough to support health and quality of life. Today, most experts emphasize that a comprehensive physical fitness program involves aerobic activities that build heart and lung fitness and keep body fat at healthy levels, and strength-building exercises such as calisthenics and weight lifting that build all of the major muscle groups of the body (6).
To summarize, your exercise program should build fitness in three ways:
* Muscular fitness: Strong and enduring muscles that are developed from near-daily calisthenics (e.g., push-ups, sit-ups, chin-ups, leg squats), weight lifting, and intense manual labor (e.g., chopping wood, digging, carrying loads).
* Aerobic fitness: A fit heart and lung system that is built up from regular vigorous whole-body activity, such as swimming, cycling, running, uphill walking, basketball, soccer, and other similar sports.
* Healthy body weight: An optimal amount of body fat that is earned through careful eating and at least 1 hour of physical activity each and every day.
The Table shows how health is improved and disease is prevented when all components of fitness are developed.
I urge you to build up both muscular and aerobic fitness through a comprehensive program. Having a muscular body without a good heart is similar to having a Jaguar with a Volkswagen engine. But the converse does not make much sense either.
1. Gaines, C. Yours in Perfect Manhood, Charles Atlas: The Most Effective Fitness Program Ever Devised.
New York: Simon and Schuster, 1982.
2. Bowerman, W.J., and W.E. Harris. Jogging.
New York: Grosset & Dunlap, 1967.
3. Cooper, K.H. Aerobics.
New York: Bantam Books, Inc., 1968.
4. Cooper, K.H. The Aerobics Way
. New York: M. Evans & Co., Inc., 1977.
5. Cooper, M., and K.H. Cooper. Aerobics for Women
. New York: M. Evans & Co., Inc., 1972.
6. American College of Sports Medicine. ACSM's Guidelines for Graded Exercise Testing and Prescription
. 7th ed. Philadelphia: Lippincott Williams & Wilkins, 2005.
7. Wolfe, R.R. The underappreciated role of muscle in health and disease. American Journal of Clinical Nutrition
8. Pedersen, B.K., and B. Saltin. Evidence for prescribing exercise as therapy in chronic disease. Scandinavian Journal of Medicine & Science in Sports
16(suppl 1):3-63, 2006.