The Physical Determinants of Pain

By Duke Autret, Myotherapist

When it comes to understanding and addressing pain, as well as the psychological and social factors it's important to also consider the physical determinants that can contribute to discomfort. In this blog post, we will explore the key physical determinants of pain and how they can impact our well-being. By recognizing and addressing these factors, we can work towards reducing pain and improving our overall physical health.

Let’s start with the fundamental root cause of all structural problems from the physical standpoint, which is to say Overload. From here we'll look at the myriad of ways this comes into play.
When we break it down further, there can be two distinct categories of overload.

​Acute Injury vs Chronic Overuse
The obvious one is of course an injury, an acute trauma to some part of the body and the details of that event will determine what structure/s may have been damaged. 
Then there is the Overuse side of things. The main difference between acute injuries and chronic overuse is the timing and underlying causes of the pain. Again, Acute injuries often occur suddenly as a result of a traumatic event, such as a fall, an impact, a sudden or over-reactive movement, or sports-related incident, causing immediate pain, swelling, and limited mobility. On the other hand, chronic overuse injuries develop gradually over time due to repetitive movements or prolonged stress, resulting in persistent pain, localised tenderness, and perhaps stiffness. First course of  management for acute injuries will usually involve rest, ice, compression, and elevation, while chronic overuse injuries require a multifaceted approach addressing underlying causes, modifying activities, and implementing rehabilitation strategies to restore function and reduce pain.
So to sum up, while they are both still forms of Overload, one is from a sudden or Acute load, and the other from repetitive and/or prolonged Chronic loads.

Furthermore there are two main divisions when it comes to the tissues or structures of the body that may be overloaded. 1) Passive structures such as ligaments, cartilage, joint capsules, discs, bones etc. And 2) Active structures which are the muscles.   
And how does overload of the active and passive structures/tissues of the body occur?
Here are the main reasons. 

Weakness 
Weak muscles are themselves more easy to overload, and more quick to fatigue which not only can lead to muscle stress and resulting tightness, soreness and referral pain (pain which travels/radiates out to other places), but therefore can also can put additional stress on our joints and lead to pain and discomfort. Another phenomenon that can happen due to muscle weakness somewhere is that other muscles may have to work harder to compensate for it and thus then those muscles will be overworked/used/loaded.
Whether it's due to a sedentary lifestyle, lack of exercise, or specific muscle imbalances, weakness can contribute to musculoskeletal issues. Strengthening exercises targeted at the weak muscles can improve their capacity for load tolerance, overall function, resilience, and can help alleviate pain.

Mobility (hypo or hyper)
Restricted joint mobility and limited muscle flexibility can contribute to pain and discomfort. When adjacent regions to an area of complaint lack mobility, it can result in overloading that specific area. For example, a sore knee with normal range of motion may experience overload due to limited mobility in the joints above and/or below, such as the hip or ankle. On the other hand, excessive joint mobility, known as hypermobility, caused by weak muscles, stretched ligaments, or a fairly common genetic conditions (known as generalised hypermobility and/or Ehlers Danlos syndrome) can all lead to joint instability (and are susceptible to poor positioning and frequent subluxation or even dislocation when severe), muscle tightness, and subsequent pain or discomfort. Balancing joint mobility and stability is crucial in maintaining optimal musculoskeletal health. 
Other factors such as poor posture, prolonged sitting, and lack of stretching or movement can lead to stiffness and reduced flexibility and/or pulling an overstretching of passive structures. 
Incorporating regular mobility exercises, and mindful movement can enhance joint mobility, and alleviate pain. As can stability, strength, muscle endurance programs.

Movement patterns 
The way we move and perform daily activities can have a significant impact on our physical well-being. Dysfunctional movement patterns are ones that once again load up our structures more than necessary. Things such as poor technique when lifting, twisting, or repetitive motions. All of which can strain our muscles and joints and lead to pain. 
Different from strength, Movement patterns are more to do with muscle control, or how you use and regulate any muscle power, and can also be thought of as a repertoire of skills, many ways and techniques or patterns you could move to achieve an action or task. If your repertoire becomes limited then you end up having to use the same few patterns over and over again, leading once again to overload.
Mindful movement practices like pilates, taichi, feldenkrais and yoga, functional training, and ergonomic adjustments can help optimise motor control and movement patterns and reduce the risk of pain and injury.

Alignment & Posture 
Poor posture is basically a repeated and prolonged overuse of body parts and positions and can place excessive loads at certain areas and therefore stress on our joints, muscles, and connective tissues, leading to pain and dysfunction. Factors such as prolonged sitting, improper lifting techniques, and repetitive movements can contribute to postural imbalances.
Joint mechanics also requires good alignment when moving through ranges of motion, when a well centred joint has to move it can glide without any friction at its pivot point, and so whether in static positions or dynamic movement practising good posture and incorporating exercises that promote good alignment can help alleviate pain and improve overall function by better distributing the loads across the body rather than having it overly concentrated in certain places.

Muscle imbalances
Muscle imbalance refers mainly to relationships of length and stiffness between muscles and can occur for example when certain muscles become overactive or tight, while others become weak or underactive. It’s a kind of shorthand way of conceptualising the result of any of the above combinations, and then feeds back onto itself. So for example, poor movement patterns or long standing postural patterns can turn into muscle imbalances, which then in turn becomes more likely to reinforce poor movement and posture as well as joint positioning (joint centration), new compensations etc., and thus increased stress on areas of the body. Corrective exercises with an aim of restoring balance to opposing muscle groups via targeted stretching and strengthening to help rebalance muscles and joints and offload the irritated tissues.

Sedentarism 
Sedentarism, or a sedentary lifestyle (characterised by a lack of physical activity), is (perhaps the) one factor that contributes to all the ones above simultaneously. It leads to atrophy (reduced muscle size/fibres) of muscles within just days, which in turn means that weaker muscles are more prone to fatigue and overload, which can result in muscle stress, tightness, and referral pain. Additionally, weak muscles may cause joints to become hypermobile, and/or other muscles to compensate, and all to become overworked. A loss of mobility can often be caused by prolonged sitting and lack of movement, can lead to restricted joint mobility, reduced muscle flexibility, and limited range of motion through adaptive tissue length and pliability loss. This can contribute to pain and discomfort, especially in adjacent regions of the body or vice-versa. Dysfunctional movement patterns, such as poor lifting techniques and repetitive motions, can strain muscles and joints, while limited movement repertoires can lead to overload and pain. Additionally, muscle imbalances, characterised by overactive or tight muscles and weak or underactive muscles, along with malpositioning of joints, can alter joint mechanics and movement patterns, resulting in increased stress on specific areas. Poor alignment and posture, often influenced by factors like prolonged sitting and improper lifting, can further exacerbate tissue stress. To address these issues comprehensively and reduce pain while improving overall physical well-being, including metabolic and mental health, it is crucial to incorporate regular strength and mobility exercises, mindful movement practices, and promote good posture.


To recap and distil all of this, one final important distinction commonly made is simply whether a condition is a Movement issue or a Workload Management issue. After considering all the information we have looked at, it becomes evident that both of these are essentially 'load' issues, but with different underlying causes. 
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The first, a Workload Management issue, arises from overloading tissues beyond their normal capacity, either through excessive force/weight or prolonged duration/volume. On the other hand, a Movement issue stems from a lack of control and alignment in muscles and joint structures, reducing their capacity and tolerance to handle usually acceptable loads.

Although when simplified, load is at the base of all the physical determinants, it’s important to recognise also that there can be combinations of each and any of these various factors mentioned where the effects of overload can be compounded. For example a suboptimal movement pattern which has become repetitive, and then might be performed with extra load than usual (say a heavier item this time), and maybe even working harder to compensate for a currently stiff neighbouring joint, possibly throw in some muscle imbalances and/or joint instability and voila.. All these can obviously add up to a bit of a sore spot! Recognising these differences means we can tweak the way we might approach remedying the situation.

By addressing the physical determinants of pain, including weakness, insufficient mobility, muscle imbalances, alignment and posture, and movement patterns, we can take proactive steps towards reducing pain and improving our physical health. It's essential to work with healthcare professionals, such as physical therapists or exercise specialists, who can provide guidance and develop tailored strategies to address these factors. Embracing regular exercise, maintaining proper posture, incorporating mobility work, and adopting mindful movement practices can contribute to a pain-free and active lifestyle. Remember, each person's experience with pain is unique, so it's important to consult with a healthcare professional for a comprehensive assessment and personalised recommendations.