Improving aerobic fitness
Improving aerobic fitness

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2 Principles of training

When designing training sessions or programmes, it is important to consider the principles of training which include the principles of overload, progression, specificity, individual response and reversibility. These principles apply to all components of fitness, not just aerobic fitness,


In order to increase our fitness, we need to ‘overload’ our body systems. For example, to increase our aerobic fitness we have to ‘overload’ the cardiorespiratory system or make it work harder than it is used to. This can be achieved by increasing the frequency, intensity or duration of training to create an overload. We will examine this in Section 3.


Overload needs to be applied in a steady progression; that is, we shouldn’t do too much too soon. If someone who has never run before has a goal of running a marathon, we would not get them to try to run twenty-six miles straight away. We would start them off running a much shorter distance and then gradually increase the distance over a period of time.


Specificity means that all aspects of training are specific to the needs and demands of the activity that the individual is training for. Specificity involves replicating the movements of an activity in training. For example, a long distance runner would obviously need to perform running training, but they would perform very different running training to that of a sprinter. Specificity refers to ensuring the training is designed to maximise the performance in response to the demands of the sport or activity.

Individual response

Individuals will always be unique. With uniqueness comes a challenge to trainers, coaches, and instructors. It is important to remember that if you coach or instruct a group of people they will all respond differently to the training sessions you set. The challenge is to find the right training load to meet the needs and responses of each individual. People respond to training in different ways and this is due to many factors, including their genes, their stage of development or maturity (e.g. children vs adults), the fuels they consume (i.e. nutrition), how much rest they get (including the quality and quantity of sleep), their pre-existing fitness levels, any underlying illness or injuries, and ultimately, their motivation to train (Sharkey and Gaskill, 2013).


This principle can be summed up by the phrase ‘If you don’t use it, you lose it’, which means that while training/exercise using the principles of overload and progression will increase our fitness, not exercising will lead to a decrease in our fitness.

The principles of training must be considered when designing a programme to allow the full potential of each individual to be realised. In order to apply the principles, we need to be able to adjust the training load. There are four ways in which we can adjust the training load – by changing either the frequency, intensity, time or type of training (FITT). We examine FITT in the next section.

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