If you walk in to just about any gym, you see people using a wide variety of weights. Some will be lifting the heavy weights for a few repetitions while others may be lifting small dumbbells for more repetitions. Is there really a difference in how your muscles react to the different amount of weight you lift? The answer, based on a new study, may surprise you.
When you lift weights, you are working your skeletal muscles. The skeletal muscles are composed of muscle fibers held together with connective tissue. In general, skeletal muscles attach at an origin, or large area of bone, with one end. The other end, called the insertion, tapers into a tendon and attaches to another bone. Your muscles increase in size through hypertrophy, which is an increase in the size of existing muscle fibers. Exercising muscles pushes them and causes small tears to the fibers. The body sends out satellite cells to repair the damaged proteins and results in increased fiber size.
Light Versus Heavy Debate
Fitness experts have long argued that in order to grow muscles, one must lift heavy weights. People believed that lighter weights and more repetitions were good for increasing muscle endurance but not for muscle growth. However, a 2012 study published in the Journal of Applied Physiology shows that more is not always better when it comes to weight.
For the study, researchers looked at how muscles reacted to different resistance training. Using 18 young, healthy male volunteers, researchers determined the maximum weight each participant was able to lift one time in a knee extension. Researchers assigned each participant a different training program for 10 weeks. The first group performed one set at 80 percent of their maximum load. The second group performed three sets at 80 percent while the third group performed three sets at 30 percent. Each group performed as many repetitions as they could with their assigned load in each set. Workouts took place three times a week for 10 weeks. The study results showed that both groups that performed multiple sets showed significant gains in muscle volume.
Benefits of Lighter Weight on Joints
The fact that this new study shows that people lifting lighter weight with more repetitions can achieve similar muscle gain results as people lifting heavier weights offers many benefits. People with joint problems, such as arthritis, have avoided weight training because the heavy weight is too much. Now they can achieve the same goals while using a weight that is safe for their joints. Check with your physician before beginning any exercise program.
- IDEA: How Do Muscles Grow?
- BBC: Muscles – Skeletal, Smooth and Cardiac
- Journal of Applied Physiology: Resistance Exercise Load Does Not Determine Training-Mediated Hypertrophic Gains in Young Men
- Arthritis Foundation: Introduction to Exercise
- Arthritis Foundation: How Weight Lifting Can Help Rheumatoid Arthritis
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