Weight lifting, also known as resistance training, increases muscle size. But many women and some men avoid lifting heavy weights for fear they'll end up looking like the Incredible Hulk. Under certain conditions, lifting heavy weights can produce a big, bulky body, but it doesn't have to. Tailoring your lifting program to your goals can give you a shapely, toned body without making you grow bigger, according to exercise physiologist Cedric Bryant, Ph.D., chief science officer for the American Council on Exercise.
How Muscles Get Bigger
Resistance training causes trauma to the muscles, resulting in mini tears that the body repairs by making the muscle bigger and stronger. This is known as muscle hypertrophy. According to a University of New Mexico research article, this process causes cells located on the outside of muscle fibers to bond together, fuse to muscle fibers and form new muscle protein. For this process to occur, the muscles need to rest for 48 hours following a weight-lifting session, Bryant says. During this resting process, new protein is produced and muscles get bigger.
Big Weights, Big Muscles?
In order to build muscle, you must lift weights that are heavy enough to trigger the trauma-and-repair process. But doing this isn't enough to make you big. "Attaining big, bulging muscles also requires consuming large amounts of calories and many more hours of training than most people would want to do," Bryant says. Challenging your muscles enough to strengthen them can be done with a moderately-heavy weight. How heavy? Your muscles should feel fatigued, but not exhausted, after 10 to 12 repetitions with the weight, according to Bryant. Because no two people are alike, there is no one suitable amount of weight for everyone.
Gender Differences
There is a limit to how big muscles can get in women due to gender differences in body size, body composition and hormone levels, according to the University of New Mexico article. The researchers report that testosterone, a male hormone, tells the pituitary gland's growth hormones to trigger the muscle thickening and lengthening that are important for muscle growth. Additionally, testosterone interacts with muscle fiber DNA receptors, resulting in production of protein, according to the researchers. Women don't have enough testosterone to get big, bulging pecs even with heavy weights. Men have approximately 40 percent more muscle mass than women, Bryant says.
Get Shapely, Not Bulky
To achieve a shapely and toned body without getting bigger, combine aerobic workouts with weight training. Cardiovascular exercise is needed to burn fat. Bryant recommends 30 to 60 minutes of jogging, brisk walking, cycling or swimming on your days off from weight training. Weight training supercharges your cardio workouts. With the power and strength you've gained through weight training, you'll be able to run or swim with more intensity and longer distances, burning extra calories and shedding more fat. The result will be a slim, shapely body without getting bigger.
References
- Cedric Bryant, Ph.D, exercise physiologist and chief science officer for the American Council on Exercise
- University of New Mexico: How Do Muscles Grow?
Member Comments