Training

Exercise load – what is it?

Jun 19, 2020

Exercise load in runners

Some of you may have heard this word quite a few times in the exercise world. It may have been in the form of exercise load, the principle of overload or even overload injuries.

So what is Load?

There are many definitions for load, but we want you to focus on these Google definitions:

  • a weight or source of pressure borne by someone or something
  • the amount of work to be done by a person or machine
  • a burden of responsibility, worry, or grief

From these definitions, we may say that load is any work you have to do in order to achieve your goal. This may be physical as with exercise, emotional (i.e. overcoming grief), or even intellectual (i.e. learning), etc. In all of these areas, for you to achieve your goal you will be required to repeatedly do a certain activity to grow in that specific area of your life. We may call it practice or training but the principle remains the same, the more you do, the better you will get and the more you will be able to progress the difficulty level.

In comes Overload Principle…

This is an exercise principle where we slowly increase the difficulty level of the exercise in order to overcome adaptation. Adaptation is the principle whereby, after being subjected to a certain load repeatedly, we become more efficient, which means we use less energy and effort to do the same amount of work. This is why after a while things start getting easier. Overcoming adaptation is what allows us to become increasingly better – that may mean becoming stronger, faster, having more endurance, skill, or a combination and this is what guides most of our progressions in physical activity.

Then we have… Overload Injuries

These are injuries that occur when we load ourselves more than we can actually bear. We increase the load we are subjected to, either too much or too soon, where we have not allowed for adaptation to occur to allow us to move on to the next level.

Overload presents itself in many ways. Physically we have muscle strain, ligament sprains, tendinitis; emotionally and mentally we have stress and burnout. That is why, when it comes to exercise we hear about progressive overload. This means a guided and measured increase in load.

Types of Load

There are different types of load, as shown below:

Types of load - Run Life

  • Type: The type of activity, this may be cardio, HIIT, sprinting, long-distance running, jogging, weight-lifting or even type of training within a certain modality. For example in weight lifting we may do pyramid training, eccentric load, supersets, etc.
  • Frequency: How often you train within a certain time period, this may be a day, a week, a month or even a year.
  • Intensity: How hard do you train, how much effort you put in each session (think of it as % of your full effort). This may be through speed, distance, weight.
  • Duration: How long do each of your sessions last.
  • Terrain: The environment where we do our activities such as treadmill, road, track, trail, pitch, turf, swimming pool, open waters, etc.
  • Equipment: Type of shoes, weights, clubs, etc.
  • Disease: Different conditions put an added strain to our bodies thus loading our systems. The treatment of these conditions are also a factor to consider.

When it comes to exercise, the general principle is that you increase your load between 5-10% per week in order to avoid injuries. This percentage is an overall percentage, meaning you shouldn’t change your type, duration and frequency each by 10%, but that the aggregate of all change should be no more than 10%. When it comes to things like type of exercise, terrain and equipment, which are harder to measure in terms of percentage, it’s advisable that these be changed individually and given time to adapt into the new factor.

The principles of type, frequency, intensity, duration, terrain (think environment) may also be applied to emotional and mental load. However, the load management plan should be done with a trained professional, i.e. a psychologist. As a physiotherapist, I would simply like to make you aware that your emotional and mental state affect your body and contribute to some of the conditions we see, so it’s important to be aware of them and manage them appropriately.

Last but not least- Rest

One of the most overlooked principles in our lives is rest. Rest is time for us to not only recover our energies but it is also the time our body repairs itself, our brain makes new connections and our body organises the structures allowing us to function optimally. Rest affects every single aspect of our being, and no matter what your activity level, lifestyle, or status, we all need this time. Rest may be active, meaning we rest a certain type of activity, joint, muscle or it may be passive such as stopping all activities.

I hope this article has been insightful and has given you some food for thought for your training and lifestyle overall.

Chantal Pretto


Chantal Pretto from Pretto Physiotherapy specialises in sports and orthopaedics. They take a complete biomechanical approach to identify the underlying causes of the problem, rather than just treating the symptoms. They specialise in working with runners, as well as other sportspeople. Read more here.

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