First Time User? Enroll now.
Find Vaccine information, visitor restrictions, and additional resources
Home > Health Library > Healthy Muscles
Muscle fitness is one of three important types of overall physical fitness. The others are aerobic fitness and flexibility.
When you increase your muscle fitness, you'll notice that you can carry heavy grocery bags more easily, pick up children without feeling as much strain, or carry heavy items longer before you get too tired to continue.
Benefits of muscle fitness include:
Muscles become stronger when they are used regularly, but especially when they have to work against something. This is called "resistance."
For example, you use your arm muscles when you bend your arm at the elbow. But when you do the same movement with something heavy in your hand, your arm muscles are working against more resistance.
"Resistance training" means using things like weights, rubber tubing, or certain exercises to make your muscles stronger. It's a 3-step process:
A resistance-training program to increase muscle fitness can include:
One part of muscle fitness is strengthening the muscles of your trunk. This is called core stabilization.
Core stability benefits everyone, from older people to top professional athletes. It can help you have better posture and balance, and it can help protect you from injury.
Experts say it's best to do exercises to strengthen muscles at least 2 times each week.footnote 1 Examples include weight training or stair climbing on 2 or more days that are not in a row.
"Repetitions" and "sets" are terms used to describe how many times you do a specific exercise.
The number of repetitions and sets you do depends on your goals. If you want to gain strength, do a few sets of a few reps with heavy weights. But you may want muscular tone and endurance, which means a few sets of many repetitions with light or medium weights.
For best results, use a resistance (weight) that makes your muscles tired after 8 to 12 repetitions of each exercise. As you build muscle strength, you'll notice that you can do more and more of each exercise. Some people will see a change in the way their muscles look, but others will not see a change for a long while. A more important sign of progress is how many repetitions and sets of an exercise you can do, or how much easier it feels to do them. This means that your muscle fitness has improved.
It's always a good idea to talk to your doctor before starting a resistance-lifting program, especially if you have high blood pressure, heart disease, or joint problems.
By starting slowly and using the right technique, you may find that weight training is an enjoyable and effective way to build strength.
U.S. Department of Health and Human Services (2008). 2008 Physical Activity Guidelines for Americans (ODPHP Publication No. U0036). Washington, DC: U.S. Government Printing Office. Available online: http://www.health.gov/paguidelines/guidelines/default.aspx.
Other Works Consulted
Anspaugh DJ, et al. (2011). Building muscular strength and endurance. Wellness: Concepts and Applications, 8th ed., pp. 111–137. New York: McGraw-Hill.
Williams MA, et al. (2007). Resistance exercise in individuals with and without cardiovascular disease: 2007 update: A scientific statement from the American Heart Association Council on Clinical Cardiology and Council on Nutrition, Physical Activity, and Metabolism. Circulation, 116(5): 572–584.
Current as of:
May 12, 2021
Author: Healthwise StaffMedical Review: E. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family MedicineHeather Chambliss PhD - Exercise Science
Current as of: May 12, 2021
Author: Healthwise Staff
Medical Review:E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & Heather Chambliss PhD - Exercise Science
To learn more about Healthwise, visit Healthwise.org.
© 1995-2021 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.