Injury Prevention

If you are involved in sports or physical activities long enough you have probably experienced an injury of some kind - a sprained ankle, “tendonitis”, sore knees, or worse, torn cartilage or a broken bone.

Injuries vary widely in type and severity with some resulting in no time lost and others many months off, or even career ending.  But no matter the injury type, the million-dollar question is “Can we prevent injuries and if so how?”  Good question and I believe the answer is easier than most think.

Before we can prevent injury, it helps to understand some of the causes.  Injuries tend to be categorized as acute and chronic.  Acute injuries are typically traumatic in nature like a blow to the side of the knee or a fall off of a bike.  Acute injuries are difficult to prevent because the causes tend to be out of our control. 

Chronic injuries on the other hand typically have no obvious cause, progress slowly, and the symptoms are often vague or “minor”.  If not dealt with early, these vague and ‘minor’ symptoms can ultimately progress into an injury that results in forced time off from your sport or activity or even surgery. 

But despite not always readily apparent, chronic injuries do have a cause and most are preventable.  Chronic injuries are usually traced to “overuse” and come in the form of repetitive stress, or simply “doing too much too soon”.  Repetitive stress involves performing the same movements over and over without adequate strength, endurance, or recovery.  “Too much too soon” often relates to the frequency, volume, and intensity of a given activity or training program and are also referred to as “training errors”.   The bottom line is that if the stress of an activity or exercise exceeds the physiologic tolerance of the tissue, the result is often an accumulation of micro-trauma, inflammation and pain.

Variables contributing to chronic injuries include inadequate preparation or training habits, poor fitting equipment, inefficient technique and inadequate recovery time - variables that are under our control.  And this is the key: we have the ability to control and manipulate variables within our training program and activities that can prevent most, if not all, chronic injuries. 

But as preventable as they may be, chronic injuries can be difficult to treat.  The causes can be subtle and multi-factorial, the treating clinician must often be a good detective.  Is it the training program and if so, what part of the program?  Is it the frequency, the volume, the intensity or a combination of the three?  Is it improper footwear, poor bike fit, improper technique or body mechanics?  Does the recovery time match the training load?  All variables have to be considered when trying to find the cause and developing an appropriate treatment and prevention plan.

Considering the above, the principles of injury prevention can be categorized into what I refer to as the PETR Principles: Preparation, Equipment, Technique and Recovery. 

• Preparation refers to a conditioning program that incorporates appropriate warm up, mobility, strength, endurance and balance training. 
• Equipment includes utilizing the appropriate activity specific equipment such as proper footwear for running or hiking, bike fit for cycling, racquet fir for racquet sports, and golf club fit, etc.  
• Technique refers to correct form and body mechanics when training and performing.
• Recovery includes adequate rest within a training program so the body can replenish, adapt and get stronger.

Preparation

Preparation is the foundation of injury prevention.  Simply speaking, the goal of preparation is to increase the bodies’ physiological tolerance so the mechanical demand of any particular sport or activity does not stress it to the point of injury.  The better prepared the body is, the greater the tolerance for stress.

Preparation typically involves a goal oriented conditioning program that incorporates appropriate warm up, mobility, progressive strength training, endurance and balance exercises and may be general or specific to an activity or sport depending on the goals. 

One such method is a “periodized” training plan, which is a science-based training method that separates training into phases or cycles and progresses from general to specific.  These cycles manipulate the frequency, volume and intensity of individual workouts in a way that most efficiently prepares you for the next phase while allowing for sufficient recovery.

Warm up

The purpose of warm up is to prepare the body for activity and promote efficient movement patterns.  Restricted muscles, connective tissue and joints create compensations within and between our moving parts and promote dysfunctional and inefficient movement patterns that can ultimately lead to inflammation, pain and injury.  The more efficient our movement patterns, the less stress on our muscles, connective tissue and joints.  Proper warm up improves mobility, helps tune the neuromuscular system, optimize force production (aka strength and power), coordination and reinforces movement patterns specific to the activity. 

Methods for warm up vary but typically include both dynamic mobility exercises and static “hold and release” stretches.  Although there are many theories and arguments for both, when applied and performed properly, each technique can supplement the other and can be successfully utilized to promote optimal mobility and movement efficiency.  Different activities have different movement requirements, but for optimal preparation and performance, as well as the prevention of injury, a comprehensive warm up specific to an activity needs to be a part of every athlete’s routine. 

Other benefits of flexibility and mobility

• Helps maintain technique and posture during activity
• Facilitates recovery of the central nervous system
• Improves blood flow to help nourish and rid of waste byproducts in muscle tissue
• Reduces scar tissue formation associated with immobilization and injury
• Promotes relaxation

Strength

Strength increases resistance to injury by improving the bodies’ ability to absorb and distribute the stress of activity and sport.  Strength training increases the strength of muscle, tendon, ligament, connective tissue and bone and improves joint and spine stability.  Ultimately, we are only as strong as our weakest link.  Cliché, but true.  Strength also contributes to power, endurance, coordination, and balance and improves overall movement efficiency.  You don’t have to be an “athlete” or involved in sport to benefit from increased strength.

Our muscles, tendons, connective tissue and bones get stronger and resist injury by adapting to progressive resistance or overload.  Adaptation is the process by which the body increases its tolerance level to exercise or other physical demands as long as adequate recovery is allowed.  Strength training should consist of progressive overload so that adaptation occurs most effectively. 

Strength training can be performed using machines, cables, dumbbells, barbells, medicine balls, elastic bands and cords and even body weight.  Exercises can isolate single muscle groups or multiple muscle groups that mimic specific movements.  The latter are often referred to as “functional” exercises because they include movements that occur in real life and sport and often require the body to provide the leverage and balance for the movement, not a machine. 

 The advantages and disadvantages of a particular strength training method will depend on your goals, strengths and weaknesses, and what “phase” you happen to be in, whether general or specific.  Keep in mind that most real-life activity and sports occur with our feet on the ground with the body providing the leverage for the movement.

Other benefits of strength training

• Improved ability to maintain proper postures and form within your sport such as when swimming, cycling or running.
• Improves coordination by improving the intensity, timing and correct sequence of movement patterns.
• Can help to reduce strength imbalances between muscle groups.
• Provides for quicker rehab time if you do get injured.
• Improved confidence.  Improved strength equates to better performance and better performance will increase your confidence.  Confidence breeds success so confidence cannot be overlooked.

Endurance

Endurance comes in different forms, involves different physiological systems and is sport specific.  For the purpose of injury prevention, endurance refers to the body’s ability to resist fatigue.  Fatigue can lead to any number of faults or compensations such as loss of strength, technique, coordination, balance, and timing.  Fatigue is not conducive to efficient movement patterns and leaves the body vulnerable to injury.  Endurance delays the onset of fatigue and helps maintain optimal performance levels and reduce the risk of injury.

Note: fatigue is not altogether “bad”.  Fatigue is a natural by-product of conditioning and when combined with proper recovery strategies, stimulates the adaptation response, which ultimately results in improved strength within fatigued structures. 

Equipment

Equipment is most often thought of as a form of protection from acute injury such as a football helmet or shin guard.  But equipment, and its proper fit, also plays a role in reducing stress and improving movement efficiency and must be considered in the injury prevention equation. This is especially true for activities that involve repetitive stress such as cycling and running.

Bike fit is a great example.  Cycling involves repetitive movement of the legs through a relatively large range of motion, against a resistance, and takes place while sitting on a fixed seat leaning forward.  This posture creates a specific geometry between the body and the bike and if not fit correctly can cause excessive stress on the knees, hips and back.  On the other hand, when fit correctly, this geometry can be optimized to produce the least amount of stress while maximizing force production.

A professional bike fitter might look at 20 or more different measurements in an effort to optimize fit and biomechanics including, but not limited to, seat height, fore and aft seat alignment, stem, frame, crank, and cleat alignment.  Bike fitting is a skill and an art and proper fit can make a significant difference in maximizing comfort and efficiency while minimizing stress and risk of overuse injury for all levels of riders. 

Other examples include proper footwear for running, court sports and field sports; golf club shaft stiffness, weight, grip and even length; tennis racket grip size and string tension to name a few.  Equipment and fit must be considered not only as a means to prevent injury, but to optimize performance as well.

Technique

There are many ways to swim 100 meters, run a 10k, hit a backhand, jump over a hurdle or hit a golf ball, but some techniques are more efficient and successful than others.  For the purpose of injury prevention, technique refers to a movement pattern required to perform an activity or sport most efficiently and successfully.  Generally speaking, the better the technique, the less the stress, the less the risk is of injury and the more successful the result.  

An example is running cadence.  Simply stated, cadence is the number of steps taken per unit of time, usually one minute.  Runners with a higher cadence (~180 steps per minute) are generally more efficient and produce less impact forces than those with a lower cadence (~160 steps per minute).  Those with a lower cadence tend to over-stride which produces more impact stress for the legs, hips and back to absorb and distribute, which can lead to overuse injury. 

A higher cadence reduces over striding by shortening the stride and promotes a foot strike that is closer to the body’s center of mass (COM).  This reduces the “braking effect”, or “loading rate”, of each foot strike.  Every time the foot hits the ground it acts like a “brake”, or resistance, that has to be overcome in order for the body to move forward and over the foot.  The further out in front of our COM the foot falls, the greater the resistance; the closer to the COM the foot falls, the less the braking effect. 

Please note that 180 steps/minute is a reference only and an “optimal” cadence for one person is not necessarily optimal for another.  Some runners may be more efficient at 170 steps per minute and others 182 or higher.  Proper technique can be learned with any movement or sport and must be considered in the injury prevention equation.

 Technique with athletic performance is important, but form and posture with general exercise such as strength training and daily activities also cannot be overlooked or under estimated in the injury prevention equation. The neck, back (think spine), and shoulders, and all of their associated structures, such as the spinal discs, ligaments and muscles, are especially vulnerable to injury during strength training.  Proper posture promotes more efficient movement patterns with the least amount of stress.  Our body’s framework, the skeleton, and the muscles that control movement are engineered to work most efficiently when aligned correctly. 

Posture is certainly worthy of an article on its own and I will update and link a past article I wrote at a later date.  Until then, when doing any lifting and when leaning or bending forward, hinge at the hips, not your spine, keep your shoulders back, and always do your best to maintain the 3 spinal curves while simultaneously engaging your core muscles.  This goes a long way to reducing unnecessary stress on spinal structures such as intervertebral discs and ligaments while optimizing muscle function. 

Final note on posture: the core is so much more than the abdominal muscles.  Imagine a girdle or wide belt of muscles that wraps around our trunk and connects to the pelvis and shoulder girdle.  Learn how to engage these muscles while maintaining the 3 curves mentioned above and train with this in mind.  A strong core provides a firm foundation for the extremities to move on and allows for a more efficient transfer of energy between them. 

Recovery

As mentioned above, preparation is a key ingredient to stimulate the adaptation process and improve the bodies’ tolerance to stress and injury.  But adaptation cannot occur if adequate recovery is not part of the equation.  The body needs rest to replenish energy stores, repair itself and build strength.  It sounds counter intuitive to many, but the body gets stronger during rest periods, not during the actual work out.  Recovery is the key to getting stronger, faster and capturing the benefits of preparation. 

Rest and recovery come in different forms, depending on the intensity of an activity or exercise.  The more intense the exercise, the more recovery needed.  Recovery might include complete rest such as sleep or days off, or ‘relative rest’ such as an easy training day.  But without adequate recovery time, rest or sleep, the body becomes more fatigued and more susceptible to injury.   

Coaching

I would be remiss if I didn’t mention the benefits of coaching within the injury prevention equation.  Few of us have the knowledge or expertise it takes to create training programs that are customized to meet individual needs and goals.  Coaching can be vital not only for producing successful performance, but also in the prevention of injury.

Conclusion

Injuries tend to be categorized as acute and chronic and occur because the body is not prepared for the demands placed on it - the stress of an activity or exercise exceeds the physiologic tolerance of the tissue and the result is an accumulation of micro-trauma, inflammation and pain. It is difficult to control the circumstance of most acute injuries, but with a little thought and effort, the majority of chronic and overuse injuries are preventable.  We have the ability to control and manipulate the variables within our training programs and activities that can prevent most, if not all, chronic injuries.

Following the PETR Principles helps the body build resistance to stress by getting stronger and removes randomness and luck from training.  Preparation conditions the body, proper Equipment and Technique reduces stress and improves efficiency and Recovery allows the body to adapt to progressive stress and get stronger.  So whether you’re a weekend warrior, a recreational or competitive athlete, proper preparation, equipment, technique and recovery are the key to preventing nagging injuries or worse: time away from an activity or sport you enjoy.  And if you have the opportunity, coaching can be an invaluable part your overall plan to help you stay injury free.

 

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