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Five areas of physical fitness

This is an excerpt from Fitness: Steps to Success by Nancy Naternicola.

Components of Fitness

Each of the five areas of physical fitness plays an important role in being fit, and one is not more important than another. Think about the components of a car: What's the use in having a nice-looking exterior if the motor is shot or the tires are flat? In comparison, weightlifters may have nice physiques but not be able to run a mile; runners may complete a mile in record time but not be able to complete a push-up.

Cardiorespiratory Fitness

Cardiorespiratory fitness is how efficiently your heart and lungs are able to deliver oxygen to the working muscle, which means it has a direct impact on both strength and endurance. The heart is a muscle and must be worked to be strong and efficient just as other muscles of the body. Not only is cardio the base for all activity, but keeping your heart in good condition also helps prevent many health problems. Following are more benefits from having a healthy heart:

  • Adds years to your life
  • Increases the HDL (good) cholesterol in the body
  • Decreases the LDL (bad) cholesterol in the body
  • Lowers blood pressure
  • Lowers resting pulse so your heart doesn't have to work as hard
  • Helps you lose or maintain weight
  • Helps prevent heart disease and stroke
  • Lowers your risk for developing diabetes
  • Reduces stress levels
  • Boosts your immune system
  • Increases energy
  • Improves sleep

Success Check

  • What is cardiorespiratory fitness?
  • Name five benefits of cardiorespiratory fitness.

Resistance Training

Resistance training involves challenging your muscles to work against an external force in order to improve endurance, increase muscle mass, and improve strength. It is imperative to include resistance training in your workout plan because strong muscles make strong tendons, which make strong and dense bones. This in turn reduces the risk of osteoporosis.

After age 20, adults lose five to seven pounds of muscle every decade. Resistance training will help stop this loss of muscle and rebuild the muscle at any age! Muscle is active tissue, so you must use it or you will lose it. Having strong, toned muscles improves your ability to perform everyday activities, including getting in and out of the bathtub and carrying grocery bags. There are many other benefits of resistance training:

  • Helps control weight (increases calorie burn)
  • Improves balance and decreases risk of injury
  • Reduces low back pain
  • Boosts stamina
  • Reduces blood pressure
  • Increases metabolism
  • Maintains or increases joint flexibility
  • Helps reduce pain from arthritis
  • Improves insulin sensitivity and glucose metabolism
  • Reduces depression
  • Improves brain function
  • Enhances appearance

Success Check

  • What is resistance training?
  • Why is it important to include resistance training in your workout?


Flexibility is the range of motion around a joint. It is the cornerstone of your workout program because your muscles move only as far as your flexibility allows. Tight joints restrict range of motion, causing you to compensate the movement by using other muscles. This can cause muscle imbalances that affect posture, performance, and movement efficiency. Loss of flexibility can also lead to lost independence; for example, you can no longer bend to clip your toenails or reach the high shelf in your kitchen.

Incorporating flexibility into your workout (at any age) can improve posture and make movement more efficient. It also aids in these areas:

  • Reduces back pain
  • Improves digestion
  • Enhances performance
  • Decreases the risk of injury
  • Improves muscular coordination
  • Enhances circulation

Success Check

  • What is flexibility?
  • Why is it important?


Balance is the ability to control your body's position in space. It involves proprioception, which is how your body takes the information it receives from the environment (such as getting up from a chair) and sends this information to the brain. This information tells the muscles what to do so they can adapt to the change and you keep your balance. When this system gets overloaded, you lose your balance. Whether you are standing still (static balance) or moving (dynamic balance), your body continually makes adjustments to keep you from falling. Although you may think that having good balance is important only for gymnasts or figure skaters, regular balance training improves posture and coordination, enhances movement and performance, and helps prevent injuries and falls.

Success Check

  • What is balance?
  • What is proprioception?
  • Why should you include balance training in your workouts?

Core Strength and Stability

Core muscles are responsible for extending, flexing, and rotating your trunk. These consist of many layers of muscle that will determine your posture. Strengthening and conditioning these muscles reduce the chances of back pain and spinal injuries, improve performance, and result in better coordination and balance. Therefore, all exercise programs should consist of a solid foundation of core work.

Success Check

  • What is the core?
  • Why is a strong, conditioned core important?
More Excerpts From Fitness: Steps to Success