It is important to note that while exercise is important in the prevention of diseases and improving quality of life, exercise alone does not guarantee good health.  Factors such as age, gender, genetics, diet, environment, safety practices and other lifestyle habits all interact to determine disability, illness and quality of life. However, exercising is one of the wellness habits with the greatest potential to improve health and well being that is under individual control.

Physical fitness may be broken down into two broad categories: performance-related fitness, and health-related fitness.  The goal of performance-related fitness is to condition the athlete to a very high level for competition. The goals of health-related fitness are disease prevention and to improve quality of life.  Although performance-related fitness is a worthy goal, the focus of this wellness course is health-related fitness.

Presently, it is difficult to determine how much (the dose) exercise a given individual requires in order to experience health benefits (the "threshold" for health benefits). The results of large, long-term epidemiological research studies seem to indicate that most people would experience significant health benefits from moderate physical activity, continued for 30-60 minutes, on most days of the week. Although the individual response might vary, this seems to be the best general advice for adults engaging in health-related fitness activities.

The components of health-related fitness include: cardiovascular (aerobic) endurance, muscular strength and endurance, flexibility (range of motion), and body weight control.
 

Cardiovascular (aerobic) endurance is an important component of overall fitness and is a measure of the hearts ability to pump oxygen rich blood to the working muscles.

Muscular strength is the maximal ability to generate force.  Muscular endurance is the ability to repeatedly apply force.  These capabilities are as important for good health as they are for competition. 

Flexibility is the ability to move joints freely throughout their full range of motion.

It is important for adults to maintain a healthy level of body fat (as reflected in body weight) throughout the life span.  Exercise has been shown to be effective in the long-term control of body weight.

As stated previously, the physical dimension of wellness interacts with the other 4 dimensions. Each dimension is important to the overall health and wellness of the individual.
 

Although this lesson pertains to "planned" exercise, an individual may develop fitness through activities that are incorporated into their daily schedule, such as walking instead of taking the bus, taking the stairs instead of the elevator, yard work, etc. If a person is more successful at achieving fitness in this fashion, and can be consistent, this may be a better approach to planned exercise.  It is simply an individual matter.

The overload principle of exercise training involves increasing the frequency, duration, or intensity of exercise beyond that which the body is accustomed.  If done appropriately, overload will lead to conditioning without undue exhaustion or injury.
 

The reversibility principle of exercise training describes a deconditioning process where the body loses its functional ability due to disuse (being sedentary). 
 

The specificity principle of exercise training means that only the muscles actually involved in the exercise session benefit by experiencing a conditioning effect.  Also, to benefit aerobically from an exercise session, a person must train aerobically.
 

The recuperation principle of exercise training states that the body requires a recovery period between exercise sessions in order to adapt to the stress of exercise.
 

Overtraining is a condition of fatigue resulting from too stressful an exercise session and/or inadequate recuperation periods.
 

The progression principle of exercise training states that the body should be gradually overloaded in phases (stages) according to the level of conditioning and individual goals.
 

The goals of the initial phase of conditioning are the establishment of an exercise habit, injury and soreness prevention, and skill learning. This "break-in" phase usually lasts 1-3 weeks and involves light exercising. If this phase is conducted appropriately, the individual should feel the exercise session is too easy--and want to overload a bit.
 

The goals of the improvement phase of conditioning are to gradually and systematically overload in order to condition to an appropriate level for wellness purposes.  For health-related fitness, it is best to increase the duration of activity before increasing the intensity of the activity.  It is important to note that an appropriate amount of exercise will eventually be reached beyond which additional overload might be considered excessive and detract from the other dimensions of wellness.  This phase normally lasts approximately 6 months if a person exercises consistently.
 

The maintenance phase of conditioning occurs when a person has reached an appropriate amount of exercise and wishes to make fitness a lifelong habit. The goals in this phase of conditioning are to prevent boredom by including a variety of activities, continued positive reinforcement, and support during those periods when exercise adherence (sticking to an exercise habit) is difficult. In the absence of the leadership of an exercise professional, an individual should seek out opportunities for reinforcement through support groups and/or reading positive materials, etc. Remaining thankful for being physically fit is always a good reinforcer.
 

A few additional tips for increasing exercise adherence are: set realistic goals which require a reasonable exercise program, make engaging in the exercise session easy (equipment, expense, travel, personnel), make exercising one of your most important priorities, have a plan for exercising or incorporating physical activities into your normal daily lifestyle, limit exercise sessions to 1-hour each day if you have family and/or work responsibilities, and adjust your exercise program instead of quitting completely.
 

Each exercise session should include a warm-up, conditioning period, and cool down. The warm-up should be a 5-10 minute period of light exercise prior to the conditioning period. The conditioning period is a longer period (20-60 minutes for aerobic exercise) in which the intensity and duration are sufficient for health benefit and/or a conditioning response. The cool-down is a 5-10 minute period (or longer if needed) of light activity during which the body gradually adjusts back to a resting state.
 

The parts of an "exercise prescription" or plan for each component of fitness should include the: method (what to do), frequency (how often), duration (how long), intensity (how hard), and progression (stages). The following lessons discuss these parts for each fitness component.