Exercise is one of the most important factors in the overall health of an individual. Listed among its
Increased capacity for physical work (strength endurance)
Increased cardiovascular (heart and arteries/veins) and respiratory efficiency
Decreased risk of coronary heart disease
Changes in body metabolism, e.g. losing weight
Delaying the physiological effects of age
Physiological effects, e.g. reduction in stress, increase in self-confidence, etc.
Basic Components of Physical Fitness
There are four all encompassing components of physical fitness and we need to briefly define each and
clarify its role
Strength is the capacity of a muscle to exert a force against resistance. Strength contributes to power and
speed and is of great importance to a majority of sports people.
Muscular Endurance is the capacity to exert a force repeatedly over a period of time, e.g. it is the capacity
of your legs to carry you 10 Km without stopping.
Flexibility is the range of motion about a joint. Improving flexibility involves the stretching of muscles and
tendons to maintain or increase suppleness, and provides increased resistance to muscle injury or soreness.
Cardio-Respiratory Endurance is the most essential component of physical fitness. It is the efficient
functioning of the heart and lungs.
The largest amount of oxygen that you can use per minute during exercise is called your maximum
oxygen uptake (MVo2). This is often referred to as your aerobic capacity.
The effort that you can exert over a prolonged period of time is limited by your ability to deliver oxygen to
the working muscles. Regular vigorous exercise produces a training effect that can increase your aerobic
capacity by as much as 20 to 30%. An increased MVO2 indicates an increased ability of the heart to pump
blood, of the lungs to ventilate oxygen and of the muscles to take up oxygen.
This means "without oxygen" and is the output of energy when the oxygen supply is insufficient to meet
the body's long term energy demands. (For example, 100 meter sprint).
The Training Threshold
This is the minimum level of exercise which is required to produce significant improvements in any
physical fitness parameter.
As your become fitter, a higher intensity of exercise is required to create an overload and therefore provide
This is where you exercise at a level above that which can be carried out comfortably. The intensity,
duration and frequency of exercise should be above the training threshold and should be gradually
increased as the body adapts to the increasing demands. As your fitness level improves, the training
threshold should be raised. Working through your program and gradually increasing the overload factor is