Is Too Much, Too Soon The Most Likely Reason You’re In Pain?

It is a term used widely within the fitness and medical world but, what does it mean and why does it link to individuals experiencing pain?

Have you been told by your physiotherapist or trainer before that you have pain due to overtraining or doing too much, too soon? Did they fully explain what this means and do you understand why rest, different challenges or loads are important within training blocks? What does exercise and load do to the body and why do we need to be careful around how much we train or run? Firstly, let’s explore some of the science behind load and exercise, what it does to the body and how this relates to injury?.

Great personal trainers and therapists will talk about how every tissue (muscle, bone, tendon, ligaments, cartilage etc.) has a breaking point, a limit to what the tissue can withstand before it is damaged. In lay terms, this is a great way to think about your body and managing your exercise load. So, why is it that your body can withstand a certain amount of exercise but eventually overtraining can lead to pain? The answer lies within what exercise does to our body at a cellular level. All exercise, which we will refer to as mechanical loading, causes a trauma and a cellular response that leads to physiological change and the promotion of tissue repair. The problem arises when we overload a tissue beyond the speed of our tissue repair and thus we have too much, too soon.

When you exercise, such as run, lift weights, perform burpees or other impact related exercises, a cellular response is initiated in the body that causes structural changes to tissues. For example, small bones that are weak can become larger and stronger in response to the appropriate load. This term is referred to as mechanotherapy and it underpins why we train and why muscles, tendons and bones become stronger and bigger as a result, and why when we outrun the speed of our tissue repair we can experience pain or injury.

As you exercise and mechanically load tissues a trigger called mechanocoupling occurs. The physical force of exercise causes perturbations and elicits deformation of the cells depending upon the magnitude, type and duration of the exercise. For example, the longer and quicker you run, the higher the number of cells that are influenced and the larger the deformation effect becomes. For the chefs out there, this is akin to tenderising a steak. The longer and harder you hit the steak the more you deform its structure.

Following the excitement and deformation of cells due to exercise, we move into what is known as the cell-to-cell communication. Part 1, mechanocoupling (above) refers to only one cell but as you exercise and cause damage to a single cell there is a knock on effect through all tissue, which is Part 2. If you have ever stood in a large crowd and been pushed from behind you can imagine the process. One person pushes into you and in turn you are pushed forwards and lean on the person in front of you. The force of that one person has a domino effect on everyone in front. This is similar to when we run. Our foot hits the ground and the ground hits us back, but the force of hitting the ground does not stop at the foot and ankle, it is dispersed up through the tissues and bones in the body. If you are a runner and have experienced a stress related injury of the hip, this is the result of the cellular process of how mechanical load moves from the foot to the hip. A stimulus in one location can lead to a distant structure receiving a new signal even though it did not directly experience the mechanical load.

Now that we understand what mechanical force and exercise does at a cellular level we reach the key and final phase known as the effector response. All forms of mechanical load lead to the promotion of tissue repair and remodelling. This is where the trauma of mechanical loads and excitement of the cells leads to an increase in protein synthesis and laying down of new tissue to the structures influenced. This is why weight bearing exercises lead to bigger stronger bones.

The overall process described above is known as mechanotransduction and is an involuntary automatic response within our body, similar to how our heart automatically pumps blood around the body or how breathing occurs. We are able to influence the rate at which the processes occur by the duration, frequency and types of exercises we perform. From walking to running, all forms of load will trigger the cellular response, which is why managing your overall exercise load across a week or month is critical to avoid outpacing the speed of tissue repair and causing damage rather that building strong bones, muscles and tendons.