Understanding Muscular Strength

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Muscular strength refers to the amount of force a muscle can produce with a single maximal effort. The size of your muscle fibers and the ability of nerves to activate muscle fibers are related to muscle strength. It is measured during muscular contraction. Building muscle strength helps with body alignment, makes performing everyday actions easier, and increases metabolism.

What Is Muscular Strength?

You might think that muscular strength is simply how strong you are: How much weight you can carry, how many pounds you can lift at the gym, or how many push-ups you can do during a workout. But the true definition of muscular strength is a little more complicated.

According to the American Council on Exercise (ACE), muscular strength is the ability to generate the maximal amount of muscle force while performing a particular exercise. But there are other factors that affect how strong you are and how much strength you have to complete daily chores or exercises. ACE provides definitions for these terms that are related to muscular strength:

  • Muscular endurance: The ability to produce and sustain muscle force over a certain period of time.
  • Muscular power: The ability to generate enough force to move weight in the shortest amount of time possible.

For example, the number of pushups you can do in one minute depends on your muscular strength, but also on your muscular power and muscular endurance.

What happens in your body to produce the effect of strength relies on several factors. The size of the muscle and the ratio of fast-twitch and slow-twitch fibers in that muscle is one component.

Then the neural connection is key, as the motor neurons must be coordinated in their firing in order to signal the muscle fibers to contract at the same time. Strength also relies on the muscle having good support for the movement of the joint, including the health of the joints, bones, ligaments, and tendons.

Muscle-Strengthening Exercise Recommendations

The 2018 Physical Activity Guidelines for Americans from the U.S. Department of Health and Human Services recommends:

  • Children and adolescents: Muscle-strengthening physical activity at least three days per week.
  • Adults and older adults: Muscle-strengthening activities that are moderate or high intensity, involving all major muscle groups, two or more days per week.

Benefits of Muscular Strength

When you improve muscular strength and muscular definition, you enjoy many different benefits, especially if you are trying to lose weight—and you don't have to be an expert bodybuilder to take advantage of them. Strength training provides benefits for exercisers of all levels, such as:

  • Building more lean muscle mass
  • Increasing metabolism
  • Reducing body fat percentage
  • Moving through daily activities more easily
  • Better sport performance
  • Burning more calories, even while at rest
  • Improved thinking processes
  • Higher self-esteem
  • Protection against major diseases, such as type 2 diabetes and heart disease
  • Reducing pain
  • More independence with age, such as by improving balance and stability
  • Preventing both acute and overuse injuries

How to Measure Muscular Strength

The one-repetition maximum (1RM) test is the standard test used to measure muscle strength. During a 1RM test, an exerciser performs one repetition of a single exercise to see how much weight he or she can lift using correct lifting technique. There is a protocol to conduct this test, which is usually done with the bench press for upper body strength and the leg press for lower body strength.

In physical therapy, a therapist may measure a client's muscle strength in two ways. In manual muscle testing, the client resists the pressure exerted by the therapist to push a body part (such as your arm) in a specific direction. This is graded on a five-point scale. A dynamometer device can also be used, with the client pressing on it to exert a force that is then measured in pounds or kilograms.

Exercise to Improve Strength and Definition

The best way to build muscle strength is to participate in a program of resistance training. Some people call it strength training or "weightlifting." But you don't have to lift weights to improve your muscles. You can do simple bodyweight exercises at home to build muscle and build strength.

Strength training improves both the size of your muscle fibers and the ability of your nerves to communicate with the muscles. So as your muscles get bigger with resistance training (muscle hypertrophy), they also become more coordinated and better able to perform movements that require strength.

Exercises that can help improve strength and definition include:

  • Squats: Squats help build your quads (thighs) and glutes (buttocks). This makes it easier to walk or run, lift heavy things, and go up and down stairs.
  • Lunges: This exercise is good for strengthening your hamstrings, which are the muscles on the back of your upper leg. Stronger hamstrings help you run faster while also providing more stability to your knee joints.
  • Biceps curls: Your biceps are the muscles on the front of your upper arms. When they are strong, it is easier to perform everyday activities like carrying groceries and picking up your kids or grandkids.
  • Pushups: Pushups work a lot of muscles in your upper body, including your chest, back, and arms. This exercise better prepares you for pushing-type movements, such as pushing a grocery cart or stroller.
  • Planks: A plank also works your upper body while strengthening your core muscles at the same time. A stronger core means better posture and improved balance and mobility.
  • Abdominal crunches: The crunch also builds strength in your midsection, as well as in your back, which some research has found may be helpful in easing chronic low back pain.

Precautions

Taking these steps can help make your muscle-building sessions safer and injury free:

  • Use good form throughout the entire exercise, from beginning to end.
  • If the exercise requires the use of weights, make sure the weights are heavy enough to provide resistance but light enough that you can lift them without sacrificing your form.
  • Increase your resistance slowly as you get stronger.
  • Give yourself rest days so your muscles have enough time to recover in between workouts.
  • Eat enough protein (lean meats, dairy, nuts, and seeds) as this is the building block of muscle.

Getting the Right Start

Before you get started with strength training, talk to your health care provider to make sure there aren't restrictions or modifications that you should follow to stay safe. If you are new to training, ask for help. A few sessions with a qualified trainer can help you to get your program off to a strong start for lasting results.

A Word From Verywell

Exercise of any kind is important for good health and to maintain a healthy body weight. Challenging your muscles regularly helps them grow bigger and increases your muscle strength.

When you do strength or resistance training two to three times per week, you build strong muscles to stand taller, burn more calories, and improve the quality of your daily activities and movement. And you can do them inside and outside the gym.

Incorporate muscle strengthening activities into your everyday routine by doing squats when you pick up laundry off the floor or lunges when moving from one room to the next. It all adds up, giving you stronger muscles as a result.

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8 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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