The Principles of Training: The Key Things to Incorporate and Consider

The Principles of Training: The Key Things to Incorporate and Consider

Kristin Kennedy-Brown - October 13, 2023

In order to get the most out of your training, you need to apply these key principles of training – overload, specificity, reversibility and variation.

Read on to learn more about these key training principles. 


Progressing and improving our fitness means that we have to put our bodies under additional stress. Applying 'overload' as a training principle will cause long-term adaptations, enabling our bodies to work more efficiently to cope with a higher level of performance the next time we train.

Overloading can be achieved by following the acronym FITT:

  • Frequency: Increasing the number of times you train per week or the number of reps you perform.
  • Intensity: Increasing the difficulty of the exercise you do. For example, running at 12 km/h instead of 10 or increasing the weight you are squatting with.
  • Time: Increasing the length of time that you are training for. For example, cycling for 45 minutes instead of 30.
  • Type: Increase the difficulty of the training you are doing. For example progress from walking to running, from accessory to free weights.



This principle relates to the type of training that you do. It should be specific to you and your chosen sport. You should train the energy system which you use predominantly (e.g. a runner and weight lifter will require different processes), and the fitness and skill components most important to your sport, for example, agility, balance or muscular endurance. You should also test the components which are important in your sport to see your strengths and weaknesses, such as imbalances, speed, power, posture etc.

So this principle means you should consider what key conditioning you can work on, in order to boost your performance.


You can lose what you've gained if it's not maintained. If you stop training then the improvements you have made will be reversed. So if you do not train for a period of time, or reduce the amount you are training, you may not be able to resume training to the same level as before, so it’s important to build the body back up progressively until you reach that level again.

You want to be careful with overtraining though. It is a very common problem when you don’t get enough rest during your training schedule, overdoing workouts to a point where it is having adverse effects on your results and progress. This should not be confused with overload, which is the planned exposure to an increased workload and the right amount of rest in-between. Without the correct amount of rest, you will suffer from overtraining and your body won’t be able to correctly and safely perform the movements you need it to.


Try to vary your training, to keep you interested and to give your body (and the muscles you’re using) a different challenge. This can be by switching up the movements to circuits in your usual training, or doing something else entirely. Many athletes will take part in a completely different sport in-between their main season to keep their fitness up whilst still having a rest! 

For example, footballers in the midst of their football training, will participate in outdoor HIIT training, running, and strength training. Their active rest day could include; golf or yoga. 

Experts recommend that training programs should limit periods of complete inactivity to no more than two to three weeks. Prolonged periods of inactivity should be avoided, and your training programme should incorporate some form of "maintenance" training where an extended break is desired.

Think about your current training. Do you incorporate the above? If not, it's worth considering each principle and adding the relevant elements into your routine, so you can maintain and progress as best as possible.

What you wear to makes a difference in how you feel and perform along the way. Castore is the premium performance sportswear brand approved and worn by elite athletes.