What is loading?

How to manage your recovery and injury risk and understand why sometimes you’re getting injured with seemingly no reason!

A lot of my active patients come to clinic with a new injury and pain that came from nowhere, with no change in their training or exercise routine. Or that they used to be able to run 5K with no pain, but suddenly they feel that this is too much and they feel pain. Then we start discussing loading - and why sometimes other things in life, seemingly unrelated, can add so much loading to your life, that you end up injured or in pain.

There is an ongoing debate on how to understand loading in the context of recovery or performance. Classically, loading is understood in a context of training and physical forces on human body – miles run, weights lifted, hours of training, intensity of training etc. There are a lot of injury prevention and recovery protocols, based solely on these kinds of data.

But as clinicians, we work in the bio-psycho-social model. This means that for the best prevention and treatment plan, we can’t only take into account the ‘bio’ part of human being – so the biological structures with all forces that are acting on them. We need to include the whole of the human being, including the ‘psycho’ and ’social’ parts too. We can’t really put the complexity of the whole human into a very small box of the tissue loading!

Loading is anything that uses the resources available in the human body. This of course includes all the mechanical data I mentioned (miles run, weights lifted, hours of training, intensity of training etc), but it also includes things such as: work environment and work stress, mental health: current and permanent status, sleep: length and quality, nutrition & diet, hydration, social support etc – these are the ‘psycho’ and ’social’ parts, and they are also very important when talking about loading.

So in essence, there are two types of loading: mechanical (‘bio’) and non-mechanical (‘psycho’ and ’social’) that added up can give us a good understanding of what are the forces that we put through our bodies, and what our current capacity of withstanding these forces is.

I often explain this concept to my patients using metaphors – these are my two favourite ones:

1. Glass and water

Your body, as well as each structure in your body (for example an injured muscle), has some capacity to bear all loading (mechanical and non-mechanical). Imagine this capacity as a glass of certain volume – and the size of the glass will be representing the status of all the non-mechanical factors, so where your body currently is: are you well rested? Eating well? Not fighting any viruses? Mentally well?

If you are in a good place, staying fit, healthy and strong, eating well & sleeping well – then your glass is bigger, and can withstand more walking running, weights or training. If you’re injured, sick, struggling with mental health, stressed at work, not sleeping well or enough – then your glass shrinks. So whatever you could do before, whatever distance you could run, whatever weights you could lift – now will be too much for your smaller glass, the 'water' (mechanical loading) will spill and will cause injury.

Or look at it that way - your muscle has certain capacity to accept various life events. And if you’re training hard then you’re taking some of this space in the glass. But if you are filling the glass with things such as: not eating enough nutritious food, not enough sleep, stress, a lot of work etc - then, if you’re still trying to train, your body will not have as many resources and may get injured!

2. Mental/energy money

So you have some amount of money to spend on your life – be it work, walk with family, gym session, run, swim or whatever you want to do from physical activity perspective. When you are in good form – you have a lot of money to spend: you can run further, lift heavier, walk longer. But if any of the ‘psycho’ and ’social’ parts are not great i.e. - you're spending more money there (stress, poor sleep etc) – then your pot of money is getting smaller. And your usual exercise routine may be just a bit too much now – and cause injury.

Sometimes the volume, type, frequency or regularity of the exercises stay the same - but this can be too much when your body deals with something else at the same time. What is taking your energy at the moment? Where is your head at? Where are you spending your mental money? What is filling your glass? Have a think about what your body is dealing with now, and how you can adjust these factors - or temporary adapt your training plan - to stay healthy, strong and uninjured!