The Five Components Of Fitness In Personal Training

Five Components Of Fitness For Personal Trainers | EMAC Certifications

The Five Components Of Fitness In Personal Training

It’s important to realize the five components of fitness in personal training to have a view of a client’s starting fitness level. These components of fitness are a total fitness snapshot. They have strong correlation with overall health and the ability of the individual to carry out activities of daily living. Most clients who seek out the help of a personal trainer have a specific fitness goal in mind. Examples are weight loss, muscle growth, or lower body fat composition (body fat). When you know the five components of fitness, you’re better able to structure a workout to achieve greater physical fitness and overall health.

Defining General Fitness

The definition of fitness is the condition of being healthy and capable to fulfill a specific role or task. This is ambiguous if you’re trying to help a client determine if they’re physically fit and what they need to do to make improvements. Fortunately, there are five components of fitness the health and wellness community agrees upon. They include:

  1. Cardiovascular Endurance
  1. Muscular Strength
  1. Muscular Endurance
  1. Flexibility 
  1. Body Composition

Each of these components of fitness are part of a fitness program. Therefore, a personal trainer should use these measurements as part of a comprehensive fitness assessment.

Cardiovascular Fitness

Other terms for this component of fitness include cardiorespiratory endurance and aerobic fitness. It refers to the body’s ability to efficiently use oxygen from the environment and deliver it to the rest of the body. This process supports basic life, physical activity, and other functions of the human body. 

Cardiorespiratory endurance is important in the definition of being fit because of the role it plays in health.  Recent research shows cardio reduces many health related risks including:

  • Cardiovascular mortality
  • Hypertension (blood pressure)
  • Diabetes 
  • Heart failure
  • Stroke 
  • Cancer

Any exercise that engages the heart and lungs for a sustained amount of time is an aerobic exercise. It also enhances cellular metabolism and helps ease the physical challenges of day to day living. Therefore, cardiorespiratory exercise is an important part and measurement of one’s fitness level.

The primary structures in this process include:

  • Lungs- Intake fresh air, remove carbon dioxide from the blood, and replace blood with oxygen
  • Capillaries- small, think blood vessels that connect arteries to veins
  • Arteries- Carry oxygenated blood away from the heart and to tissues of the body
  • Heart- An involuntary muscle that acts like a pump to push re-oxygenated blood to the tissues to the body and send deoxygenated blood back to the lungs to remove waste and get more oxygen
  • Veins- Carry deoxygenated blood from the body back to the heart

Cardiorespiratory endurance is measured by VO2 Max. This is the body’s maximum oxygen uptake and how it’s used during intense exercise. The greater a client’s VO2 max shows there are higher amounts of oxygen uptake which means they’re using more oxygen and the system is functioning more efficiently than a lower VO2 max score. This test is typically done in a laboratory setting and not as accessible for personal trainers to do with clients. Therefore, other common cardiorespiratory fitness assessments can be used. These include tests such as the YMCA step test.

Muscular Strength

The definition of muscular strength is the amount of force a muscle can produce in one single voluntary effort. For a personal trainer and fitness client, the best way to measure muscular strength is through a 1 rep max (1RM) with exercises like a bench press, squat, or pull down. Some clients will be seeking to increase muscle mass (or size) and others will be looking to improve their 1RM. Clients like these should have programs very specific to this goal. However, muscular strength with clients who want to improve general fitness will have a well-rounded program. And, muscular strength will be one part of the fitness assessment process.

Muscular strength is one of the five components of fitness because it allows you to lift something heavy when there is a need. For example, a client with good muscular strength will be able to lift a heavy box off the ground. Muscular strength is also important because of the positive benefits including:

  • Decreased body fat
  • Increased bone density
  • Increased metabolic efficiency

Muscular strength relies on Type I muscle fibers. These muscles are lower in capillaries which means they don’t have much oxidative properties. Therefore, they are quick to fatigue. The absence of oxygen during physical activity is termed “anaerobic”. Anaerobic activity can only last a few seconds before the energy supply runs out. 

Training protocols to improve muscular strength include:

  • Low repetitions in each set
  • Longer rest intervals (two to three minutes)
  • Moderate to high intensity of work (80% – 100% 1RM)

Muscular Endurance

This component of fitness is the ability of muscle tissue to produce force for extended periods of time. Muscular endurance relies on the engagement of type ii muscle fibers. These muscle fibers are higher in blood vessels and capillaries. Therefore, there is more oxygen being delivered to the muscle cells. This allows the body to sustain the movement for longer periods of time. Muscular endurance has similar benefits as muscular strength such as improving bone density and decreasing body fat. However, the endurance element of this component of fitness allows clients to sustain a movement over and over. Examples include walking up and down stairs and other household chores. It’s also helpful in:

  • Reducing injury risk
  • Maintaining posture
  • Engaging stabilization muscles

Training protocols to improve muscular endurance include:

  • High repetitions in each set (12 – 25)
  • Lower rest intervals of 20 – 60 seconds
  • Moderate intensity or weight (50% – 80% 1RM)


The simple definition of flexibility is the ability to move a joint through its full range of motion. The muscular soft tissues around the joint impact flexibility. Given that muscle tissue has elastic properties, developing flexibility involves working on the extensibility of a muscle. Research suggests flexibility can help with injury prevention including muscle strains and sprains. It also suggests it can impact balance and coordination, both of which decline with age. 

There are various factors which impact the flexibility an individual has. Some are controllable and some aren’t. They include:

  • Genetics
  • Strength of opposing muscle group
  • Joint structure
  • Body composition 
  • Sex
  • Age
  • Activity level
  • Pre-existing injuries
  • Pattern overload (repeating the same movement regularly)

Different methods to improve flexibility include:

  • Self myofascial release (SMR or foam rolling)
  • Static stretching
  • Dynamic stretching

Over the years there has been much scientific controversy around the effects of each of these types of flexibility training protocols. Here we’ll explore the rationale and use of these different forms of flexibility training.

Self Myofascial Release 

The most common application of SMR involves foam rolling. This is where the client places a specific muscle on a foam roller then applies body weight to get pressure on the muscle. The client continues to roll in a perpendicular direction to the muscle fibers positioning. During this process, the goal is to find tender areas which represent muscle adhesions. Once the adhesion (knot) is found, the client applies more pressure to the area for 20 – 30 seconds. Applying pressure to the area stimulates a receptor called the golgi tendon organs. These protective cells sense pressure or tension in the muscle. After about 30 seconds of pressure, they send a message to the brain, indicating a need for protection. In response, the brain sends a message back to the muscle forcing it to relax. This is how the SMR works. The prolonged stimulation of the golgi tendon organs issues a warning sign. The use of SMR started in physical therapy and made its way into the personal training profession. Research suggests using SMR before a workout will inhibit muscles which are typically overactive and cause problematic movement patterns. For example, if a client has tight calves, forcing their feet to turn out during walking or squatting motions, foam rolling the calves would inhibit the overactive muscles. This in turn, should allow better and more normal motion at the foot and ankle joint.

Static Stretching

The use of static stretching involves similar concepts as SMR. Static stretches are held on muscles that are tight or overactive. Holding the stretch for 30 seconds puts the muscle under tension. Again, after 30 seconds, the protective response begins and the muscle then relaxes. Static stretching can prevent injury and restore muscles to an ideal length. Research shows, static stretching results improve with SMR

There is also debate around static stretching specifically in the sports performance realm. Here, opposers of this type of stretching suggest it decreases neural drive and activity to the muscle. This is true and, therefore, an appropriate reason to avoid performing static stretches on muscles that need excitation for piriformis. For example, you wouldn’t want to do a static stretch for the gluteus maximus just before a sprint. However, using static stretching to decrease neural drive to overactive synergists or imbalance muscles can be beneficial. In the sprinting example, it might be helpful to do a static stretch of the psoas, a hip flexor muscle, before the event. Through reciprocal inhibition this will, in theory, free up neural drive to the gluteus maximus for the run.

Dynamic Stretching

Those in sports performance tend to support the idea of dynamic stretching before activity. Dynamic, sometimes known as functional stretching, In this advanced form of flexibility training, the exercises use the force production of a muscle and the body’s momentum to take a joint through a full range of motion. It’s quick and involves more functional types of movements such as prisoner squats or hip swings. Proponents of static stretching suggest this type of flexibility is only for more advanced athletes who have little to know muscle imbalances or postural distortion patterns. However, it’s common to see dynamic stretching applications in group training or HIIT classes even though the clients are only recreational athletes, not fully able to use the full range of motion. 

In addition to the physiological benefits of dynamic stretching, research suggests a psychological benefit. In these cases, research suggests that this more excitable form of flexibility training helps to get the individual in a more advanced and performance ready state of mind. 

Concluding Flexibility Training

In addition to the controversy surrounding all forms of flexibility training, there is also a suggestion it be removed from a major component of fitness. Proponents of minimizing flexibility as a major component of fitness argue for the typical person, not an athletic performer nor aging adult. Instead, this approach suggests that due to the inconsistent findings, incorporating a stretching program can detract from other, larger goals and needs. For example, consider a client aiming to lose 50 pounds and only has 30 minutes to spend each day in physical activity. This weight loss workout program should be around increasing mobility and strength rather than restoring optimal length tension relationships. This suggestion does not argue flexibility is not helpful. Instead, it points out the need for it to not have equal weight among the other five components of fitness.

Body Composition

This number refers to the percentage of fat mass a body has in relation to non-fat mass (muscle tissue, bone, water, etc.). After a body composition test, a person will get a number in percentage form. This is the percentage of body fat relative to lean body mass. It’s an important indicator of health and fitness. A high body fat percentage can lead to health risks including:

  • Type II Diabetes
  • High Blood Pressure
  • Heart Disease
  • Stroke
  • Metabolic Syndrome
  • Sleep Apnea
  • Fatty Liver Disease
  • Some Cancer
  • Osteoarthritis

Body fat percentage, instead of weight alone, is a better indicator of health than the client’s body mass index (BMI). A client’s BMI only takes into account weight and height. Therefore, calculating BMI is easy and accessible for most individuals. However, muscle mass carries more pounds per square inch than fat does. Therefore clients who have better than average muscle tone and muscle mass can appear as though they are overweight or even obese. Therefore, the best predictor of overall health and fitness levels is through the measurement of body composition. There are several ways to measure body composition. They include:

  • Skinfold Calipers
  • Circumference Measurements
  • Bioelectrical Impedance 
  • Hydrostatic Weighing


The five components of fitness are good measurements of a client’s overall fitness levels because of their correlations with health and the ability to carry out activities of daily living. Therefore, they should be part of a comprehensive fitness assessment to establish baseline metrics. However, most clients will seek to improve one specific area. For example, a client may care primarily about weight loss while another client may want to focus on cardiorespiratory fitness to run a marathon. Therefore, designing individual programs will vary depending on the client’s ultimate outcome goal with the use of the five components of fitness for process goals.


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