If there is one key concept in injury prevention for runners, it's mechanical stress — and knowing how to quantify it is particularly valuable.
The human body is the sum of different tissues, including cartilage, bone, muscle and so on. During an effort such as running, these tissues are put under strain by different forces such as tension, compression and torsion.
These different forces exerted on the human body during sport can be described as mechanical stress.
Measuring mechanical stress means quantifying the stress experienced by body tissues, in order to draw the right or wrong conclusions and thus prevent injury risk.
The amount of stress applied and the areas affected will vary depending on the physical activity. It's easy to see, for example, that the Achilles tendon won't be loaded in the same way during a running session as during a swimming workout.
Different sports represent different levels of stress. Cycling, for example, carries a low, quantifiable level of mechanical stress.
Conversely, running shows signs of significant stress. It tends to vary depending on several factors, particularly speed, which leads to an increase in the force exerted.
Po get a picture of the amount of mechanical stress accumulated on a daily basis, you would need to analyse the level of stress each daily task generates, in order to build up a sense of the mechanical stress level reached.
That's why when a person remains inactive during a rest day or a period following an injury, stress will obviously be low or even non-existent. Staying in rest mode for too long can weaken the body and make it more vulnerable to injury.
For someone who, on the contrary, engages in regular, intensive sport, the amount of accumulated stress will place that person in a risk zone and make the onset of injuries more likely.
The body therefore sends signals once the maximum capacity for adapting to mechanical stress is reached — such as pain, morning stiffness or swelling.
L'ideally, the aim is to "minimally stress" the body in order to build tolerance without exceeding the so-called maximum threshold. By staying within this range, the body adapts to stress and can increase its tolerance. Structures strengthen and allow training intensity to be increased without risking injury.
Po summarise, quantifying mechanical stress is a preventive action when no injury is present. However, pain can exist even when the maximum capacity has not been exceeded. This may therefore likely point to an injury that should be treated by a healthcare professional.
The body has a remarkable and unique capacity for adaptation, with constant evolution. It's important not to overlook the fact that fatigue, stress, fear and so on can be factors that alter the body's tolerance, making it more vulnerable.
At the same time, a state of happiness or wellbeing tends to have a more positive impact on the body and on recovery from injury. Which goes to show just how closely body and mind are linked!
