Strength vs Stability
Which is more important? Which one do you need?
Strength versus stability; the famous question many deliberate over when trying to choose the best exercises for their injury.
When we consistently go to the gym and lift weights, attend a Body Pump exercise class or CrossFit session, often it doesn’t make sense that we can still have pain when we feel strong overall. “I feel really strong, I don’t understand why I have pain,” or “I go to gym four days per week and lift heavy weights but still have a sore back” are common stories from people experiencing pain. A key component to consider when a joint may not be loading optimally is to assess how well the joint is being stabilised and controlled my surrounding soft tissues and muscles, before extra weight or resistance is added. Getting strong and lifting weights may not always be the answer if you don’t have sufficient control of the deeper stabilising muscles to engage, lengthen and contract when required. Let’s take a closer look at Strength vs. Stability and what is more important…
Stability is the ability of your muscles to stabilise and control a joint; either when resistance is applied, or throughout a movement, to transfer force. Stability of joints is achieved through active and passive structures such as tendons, capsule and ligaments, combined with neuromuscular control of muscles engaging. It is the ability of your muscles to coordinate and engage to ensure a smooth and effective transfer of force to protect and optimally load a joint.
Strength, meanwhile, is the ability of a muscle to generate, exert and transfer force or resistance. Often, stability is achieved by deep, inner muscles and their ability to control, while strength is achieved by larger, longer muscles and their ability to generate force. You could think of this concept as the layers of an onion; the deep, inner unit needs control to support and protect the integrity of the joint, whilst the outer larger, longer muscles produce force.
A great example of stability is a ballet dancer’s ability to balance on one leg en pointe whilst the opposite leg extends behind. This requires exceptional stability of the foot, ankle, knee, pelvis, hip and spine to maintain position of the joints balancing on one leg whilst the other leg is in the air. Comparably, the strength required of a weightlifter to perform a heavy deadlift requires a large amount of contractile strength of the hamstrings, gluteals, back extensors and upper body. This requires a large amount of force production of each muscle to shorten and then lengthen to produce power to lift the weight.
Joints that have a large range of movement often benefit from the activation and control of deeper muscles working to support the joint, prior to it being loaded with heavy weights and resistance. For example, the hip and shoulder joints are very mobile joints that transfer load with walking, running, carrying or lifting things. These joints offer a large range of motion, however, often can be the source of pain if the deeper stabilising muscles aren’t controlling the joint throughout the range of movement. You can have strong, force producing outer muscles but if you don’t have the underlying control of the joint, the joint may not be loading optimally.
Figure 1: The left, superficial force generating muscles.
The right, deep stabilising muscles of the shoulder complex
So what do we do; stability or strength exercises?
We would advocate for; Both! Strength training facilitates an increase in muscle mass, helps to improve bone density, brain health, supports a healthy body weight, is good for cardiovascular health and overall emotional health. Strength training even helps to reduce the risk of injury (which we would all like). Benefits of stability exercises include enhancing proprioception, balance, control, support of the joint and also assists in reducing injury. Having exceptional strength of a particular muscle group doesn’t always mean you have good control or stability of the joint throughout movement. So, we can see that both aspects are beneficial and required to have optimal balance of our biomechanics to move our bodies in ways that support and protect our joints and soft tissues.
If you are confused about what might be labelled a ‘strength’ or ‘stabilising’ exercise, below is a quick explanation to think about next time you are the gym;
STABILITY
Stability exercises are exercises that generate stiffness around a joint. These may involve core control such holding a plank with good form and not letting the back drop, or keeping good pelvic control when performing a single leg bridge. They typically focus on precision and control. Think movements that you might do in a ballet, yoga or Pilates class.
STRENGTH
Strength exercises may include a heavy squat, deadlift, overhead shoulder press, pull up or push up. However, strength exercises often need an underlying component of stability prior to increasing weight or resistance. They typically focus on force production or force transmission. Think of exercises you might do to build up muscle bulk.
This topic may be explored and elaborated much further, however we hope this outline begins to give you a basic understanding of the difference between the two.
A final note: not all exercises are suited to every person and their individual body composition. Not all surfers should do one kind of knee exercise, similarly not all swimmers need to do one shoulder exercise. Your exercise program should be tailored to your body, your imbalances, injury, needs and goals. Having an assessment of the imbalances or compensatory strategies you may be using following injury or dysfunction is important to do first, prior to designing a program. Your therapist will assess different muscles and strategies you may be using to achieve a specific task and analyse whether there are joints or soft tissues not being loaded correctly. From there, a program can be designed to address the imbalances and help create overall balance, synergy and alignment; and ultimately, pain free, good quality movement. Happy training!
