Which component of muscular fitness is referred to as the maximum amount of force a muscle or muscle group is able to generate?

The health benefits and quality-of-life outcomes of a fit musculoskeletal system (musculoskeletal fitness) are reviewed in this article. The World Health Organization suggests health is a state of complete physical, mental or social well-being and not merely the absence of disease or infirmity. Physical health includes such characteristics as body size and shape, sensory acuity, susceptibility to disease and disorders, body functioning, recuperative ability and the ability to perform certain tasks. One aspect of physical health is the musculoskeletal system, which consists of 3 components; muscular strength, endurance and flexibility. Muscular strength (dynamic) is defined as the maximum force a muscle or muscle group can generate at a specific velocity. Muscular endurance is the ability of a muscle or muscle group to perform repeated contractions against a load for an extended period of time. Flexibility has 2 components, dynamic or static, where dynamic flexibility is the opposition or resistance of a joint to motion, that is, the forces opposing movement rather than the range of movement itself. Static flexibility is the range of motion about ajoint, typically measured as the degree of arc at the end of joint movement. If strength, endurance and flexibility are not maintained, musculoskeletal fitness is then compromised which can significantly impact physical health and well-being. Many health benefits are associated with musculoskeletal fitness, such as reduced coronary risk factors, increased bone mineral density (reduced risk of osteoporosis), increased flexibility, improved glucose tolerance, and greater success in completion of activities of daily living (ADL). With aging, the performance of daily tasks can become a challenge. Additionally, falls, bone fractures and the need for institutional care indicate a musculoskeletal weakness as we age. The earlier in life an individual becomes physically active the greater the increase in positive health benefits; however, becoming physically active at any age will benefit overall health. Improved musculoskeletal fitness (for example, through resistance training combined with stretching) is associated with an enhanced health status. Thus, maintaining musculoskeletal fitness can increase overall quality of life.

Building muscular strength will help you become better able to lift and move weights and other objects, will increase your sports performance, and increases total body functioning. Daily tasks will become easier once you are stronger, including opening those pesky pickle jars.

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.

Muscular strength refers to the amount of force a muscle can produce with a single maximal effort. Muscular definition is the visual aspect when muscle shape is visible through the skin and underlying body fat.

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 maximal muscle force while performing a particular exercise. But other factors 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.
  • Muscular power: The ability to generate enough force to move weight in the shortest time possible.

For example, the number of push-ups 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. One component is the size of the muscle and the ratio of fast-twitch and slow-twitch fibers in that muscle.

Neural connection is critical, as the motor neurons in muscles coordinate their firing, signaling the muscle fibers to contract simultaneously. 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.

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

  • 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.

When you improve muscular strength and definition, you enjoy many 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
  • Improving sport performance
  • Burning more calories, even while at rest
  • Enhancing thinking processes
  • Increasing self-esteem
  • Protecting against major diseases, such as type 2 diabetes and heart disease
  • Reducing pain
  • Encouraging independence with age, such as by improving balance and stability
  • Preventing both acute and overuse injuries

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 they can lift using the correct 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 measured in pounds or kilograms.

The best way to build muscle strength is to participate in a resistance training program. 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 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 walking or running easier, lifting heavy things, and going up and down stairs.
  • Lunges: This exercise is good for strengthening your hamstrings and the muscles on the back of your upper leg. Stronger hamstrings help you run faster while 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 many muscles in your upper body, including your chest, back, and arms. This exercise 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 and back, which some research has found may help ease chronic low back pain.

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.
  • Ensure 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 between workouts.
  • Eat enough protein (lean meats, dairy, nuts, and seeds) as this is the building block of muscle.

Before you start strength training, talk to your health care provider to ensure 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.

Exercise of any kind is essential for good health and for maintaining 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.