Principles of training


This refers to activities that impose demands on the body greater than normal. Overloading body systems with higher work rates and increased loads, causes the body to respond to extra demands by adapting to the increased workload and improving performance. It is possible to improve all components of fitness by using the overload principle. This improvement can be gained in three ways:

  • By increasing the intensity of the activity – by increasing workload; i.e. run faster, lift heavier weights or stretch further than normal during training. These increases should be built up gradually over a period of time;
  • By increasing the frequency of the activity – the number of times training occurs. This means that more training sessions should be performed with shorter rest periods between them. As levels of performance rise, frequency of training is often increased. The higher the intensity of training, the less frequently they occur allowing the body to rest and recover;
  • By increasing the duration of the activity – how long training lasts. This is determined by the activity and the fitness level of the performer. The length of each training session can be increased to increase overload. Untrained individuals may only be able to work for a few minutes when they first start training. As they improve, they are able to train for longer periods of time. The type of event can restrict the duration of training. Highly intense activities can only be performed for short periods of time, whereas practising skills which make little physical demands on the body can be carried out for a much longer duration.


Stress must be placed on the body systems for training to be effective. Work done should be within the capabilities of the individual. Moving too quickly from basic skills to advanced skills does not enable smooth progression – too much stress too soon can cause injury, and the body will not adapt to too much overload. Progression occurs as the body adapts through overload. As the body adapts and begins to find harder programmes less demanding, overload must be continuously increased, otherwise progression will slow down or stop. Overload should be increased gradually in a series of progressively harder training sessions. If overload is not increased, then the training activity will become boring and performance may suffer. In the early stages of fitness and skill training, big improvements can be observed. As the body adapts, improvements in performance start to increase at a much slower rate.


Every type of exercise has a specific effect on the body. The type of training should be specific for the sport or component of fitness – training should concentrate on the particular needs of the individual and their chosen sport. Specificity also refers to particular body parts of an athlete. It is important that an individual follows a training programme that places regular stress on the muscle(s) or body system needed for the sport or activity. Specificity must also take into consideration that different sports use different energy systems, and training sessions must develop the appropriate energy system – aerobic or anaerobic. Specificity means that an individual should only work on those areas that are needed.


The body adapts to stress, getting bigger, stronger and faster through training. The reverse is also true – the body adapts to less stress (when training stops) by becoming smaller, weaker and slower. Fitness cannot be stored for future use. If training stops completely, the body adapts to lower stress levels very quickly. Anaerobic activities are affected less by reversibility than aerobic activities. The aerobic capacity of muscles deteriorates very quickly, and if the muscles are not used, they begin to atrophy (waste away, getting smaller and thinner). The effects of training are easier to maintain if they have been gained over a longer time period and are lost at a much slower rate when training stops.