7 ways to increase the chances acquiring an injury in sports

There are generally 7 major contributors to non-contact injuries acquired performing sporting like activities.   They are, in no particular order:  Age, injury history, improper warm-up, poor flexibility, posture, muscle strength imbalance and fatigue.  Two are these contributors (age and injury history) are non-modifiable, meaning, nothing can be done to change or alter them.  We cannot change our age, we can only get older; we cannot change our injury history, if I pulled my hamstring muscles during soccer practice last season, nothing can undo that now.

1. So how does age contribute to injury?  The older the athlete, the greater change of incurring a soft tissue injury.  The cut-off appears to lie somewhere around 23-25 years old (Yeah I know, that’s not old).  So once an athlete hits their mid twenties, regardless of how fit or conditioned they are, all things being equal, their injury risk will be higher then that of their younger counterparts.

2. Secondly, injury-history, previous injury to a joint or muscle automatically increases chances of re-injury.  That hypothetical hamstring injury I mentioned earlier, regardless of how diligently I rehabilitate it, my chances of re-injuring my hamstring muscles are higher than if I had never injured them.  Same story with ankle sprains, those with previous sprains are at higher risk of recurrence. The other aforementioned contributors to injury (improper warm-up, poor flexibility, posture, muscle/strength imbalance and fatigue,) are modifiable, meaning if addressed properly, their contribution to injury can be lessened or possibly eliminated.

3.  I can choose to warm-up properly prior to engaging in sporting activity, or I can ignore it, my choice.  Warming up improperly (which includes NOT warming up at all) increases chances of acquiring an injury.  Briefly, here’s the recommendation from the American College of Sports Medicine:  5-10 minutes of walking, slow jogging, or stationary cycling, followed by dynamic stretches that mimic the movements the athlete will be doing during the workout or competition.  Static stretching may be an option for some, power oriented sports participants beware (see my previous blog on this topic here).

4.  Posture, poor lumbar posture contributes to hamstring injury,  postural defects in the knees and feet have been found to contribute to overuse injuries in the lower extremities. 

5.  Poor flexibility can contribute to poor movement patterns, limited range of motion which contributes to injury.  For example, tight hip flexors can contribute to spinal injury during a bench press, as well as hamstring injury during sprinting.  

6.  Muscle imbalance, or a the inability of a muscle to absorb or withstand the forces generated by an opposing muscle at the same joint.  The agonist muscle generates force at a joint, while the antagonist muscle must contract eccentrically to slow down or “brake” the moving limb to prevent damage to the joint.  Examples include – sprinting, hamstrings must be able to withstand forces generated by the quadriceps and hip flexors, throwing, elbow flexors (antagonist) must withstand forces generated by elbow extensors (the agonist).  If the antagonist muscle cannot slow the movement down at the end of the action, injury ensues.  So muscles working in opposition must achieve a specific balance of strength and flexibility.  An imbalance is also used to describe a difference (usually >10%) in flexibility or strength among bilateral muscle groups (for example, muscles in the left leg compared to the same ones in the right leg).  When a single limb is considerably stronger than the contralateral (the other side), then risk for injury in the weaker limb increases.   

7.  Finally, fatigue.  Studies looking at leg injuries in soccer players find increased occurrences of muscle strains in lower extremities in the second half of a soccer match compared to the first half. This implicates fatigue is a contributor to these injuries.  Additionally, proper form, technique and mental focus can all be negatively affected by fatigued muscles.  A sport specific athletic performance assessment and/or a general fitness assessment can often identify asymmetry between opposing muscle groups, as well as postural deficits in hips, knees, and ankles. 

Now for the take home lessons:

• Always, always perform a proper warm up prior to sporting activity.
• Consider an appropriate physical assessment to identify muscle/strength imbalances, prior to training and competing.
• Be sure flexibility and core strength are getting attention in your training plan.
• Finally, the importance of proper training and conditioning before participation in competitive sports cannot be overstated.  While, for some a sport specific exercise training plan can mean training for weeks or months before participation in an actual competition, it is well worth it in the long run.

Hope this helps and thanks for reading!

When is it okay to perform static stretching?

Static stretching is when an individual muscle is stretched to its end point and held for 15-60 seconds.  There is a long list of different stretches, many for each muscle group.  Static stretching can increase muscle flexibility and joint range of motion.

Few debate that maintaining, in some cases improving flexibility is beneficial to athletic performance.  Fewer still would argue that static stretching is a good way to accomplish it.  The debate begins when we direct people to stretch prior to a workout or competition.  Muscles stretched statically will remain “slack” where stiffness (or more accurately, muscle “recoil”) is reduced for up to an hour or more after an acute increase in flexibility.  Purportedly, this negatively affects the muscles force producing ability, as moments during contraction are wasted “taking up slack” before contributing to force production.  There is an abundance of support in the scientific literature for this belief.  Additionally, this muscle may also be more susceptible to soft tissue injury; primarily in “explosive” sports (i.e. those requiring high amounts of speed or strength quickly, as in sprinting, jumping, and striking).

Other theories on why or how force production from stretched muscles is impaired included tissue damage from the stretching and neural inhibition.  We won’t get into the details of these here but understand that these are viable theories with support in the scientific literature, though the exact reason for diminished force production is not fully understood.  Nonetheless, even at the professional level, we still see athletes performing elaborate static stretching routines prior to practice and competition.  The longstanding belief is that the stretching will help reduce the risk of a “pulled” muscle.  However, evidence is mounting that the opposite may occur.  For example:  An athlete, in order to reduce injury and loosen up before a game, performs a stretch for his hamstrings 3x for 30s on each leg.  According to the aforementioned theory, this athlete’s hamstrings will be “slack” for the next hour or so encompassing the competition where inevitability, this athlete will be called up to run or sprint at maximal speed.  The braking effect of the hamstrings (a necessary and normal effect which occurs during sprinting), heavily dependent upon the stiffness of the hamstrings, will be diminished.  With this decrease in force generation the hamstrings must also withstand high velocity forces from quadriceps and hip flexors.  With impaired stiffness, this athlete is asking a lot, perhaps too much, from his hamstrings.  Chances the hamstrings will fail and an injury will occur are actually greater in this example.

To muddy the water a bit more, some research has shown that the detriment to muscle stiffness following acute static stretching can be ameliorated if it is immediately followed by 10 minutes or more of dynamic activity, such as running.  If farther research confirms this, it may not be helpful as many athletes simply do not have the time to warm-up, static stretch, and then do an additional session of dynamic activity, perhaps making this intervention unrealistic.  It does however, add more ammunition to the debate.  In addition to that, we have not addressed sporting activity that does not require high velocity or explosive actions.  In endurance sports, such as running, where most of the muscle force production is submaximal and occurs in mid-range of the joint (not extremes) static stretching immediately before competition appears to have little effect on performance or injury reduction.

Of course, after static stretching, muscles will return to their normal length, the time for this varies but can range from 15 minutes to over and hour.  With repeated stretching over time the length of the muscle increases.  In this case we observe the more desirable chronic adaptation, where the length is increased yet the decrements in force production do not occur.

So, with all that said, when should an athlete include static stretching in his or her routine?

1. For sports requiring large amounts of power and explosiveness, as most team sports (soccer, basketball, baseball, tennis, football, hockey), save the static stretching for after the workout or competition.  Instead, simply focus on getting the muscles warm, including dynamic movements such as marching, jogging, hopping, running, twisting, and swinging or others that mimic game play.
2. For athletes performing strength workouts, it’s probably a good idea to do the same, limit static stretching until after the workout.  For a warm-up, some walking or jogging to get warm, then perform multi-joint strength exercises at a reduced intensity.
3. For endurance athletes, such as runners, static stretching before a race or practice does not appear detrimental to performance.  So if you are one of “those” athletes who go through a static stretching routine before a run, it seems you have nothing to fear, so continuing is probably fine.

Thanks for reading!

Is a general fitness battery useful for competitive athletes?

My answer: Definitely!  A general fitness battery usually consists of five physical assessments.  Each test assess, one of the five components of fitness, which are: body composition, flexibility, cardiovascular endurance, muscle strength and muscle endurance.  One may also see assessments of balance and/or posture as well.

Examples of tests that assess the five major components of fitness are:

Cardiovascular endurance – King’s College step test, Rockport walk test, YMCA Submaximal bike test

Muscle strength – Grip strength test, 1RM leg press, 1RM chest press (each of these are generally estimated from a 3-5RM)

Muscle endurance – Push-up test, Canadian Trunk test, curl-up test, YMCA bench press test

Flexibility – Sit and reach, specific joint passive ROM assessment

Body composition – Skinfold measurement, Bioimpedence analysis (BIA)

These assessments are low-risk and appropriate for all healthy individuals.  I also like them because they have a lot of support in the scientific literature, meaning they have been tested on various populations and are valid (they test what they say they are testing) and reliable (repeated tests will provide similar scores).  I recommend assessing these components once a year, ideally following a training phase of active rest, prior to beginning a new preparation or pre-season training phase.  A general fitness assessment can provide useful insight into what the initial training phase should focus on.

Should an athlete do this instead of a more sport specific athletic testing battery?  The answer to that, it depends.  This is especially important if you are an athlete returning to competitive play after a long layoff.  Tests for power, agility, and speed, as well as exercises and drills to improve these attributes are often done at high velocity, and thus can be risky for the unprepared athlete.  Hence, athletes should be fit before taking on more advanced training.  For athletes who have been consistently training, many of the above mentioned tests are easily integrated into a sport-specific athletic testing battery (which, as mentioned in an earlier post, should be happening 3-4 times per year).  So once per year, the athlete could do an integrated test battery, and the other times stick with the sport specific athletic testing.

Depending on the training phase the athlete is entering, he/she should select tests that reflect the goals of that training phase. In the early training phase, weeks prior to the competition, the athlete should be focusing on general fitness components, which could be strength, cardiovascular endurance, or body composition.  In later training phases, still well prior to competition, transition into a more sport specific focus.  Thus it makes sense to do the general fitness testing initially, then use a more sport specific athletic testing battery to assess progress the later training phases.  Remember, the athlete should be relatively fit before undertaking a sport-specific training phase, which typically entails more complex and advanced routines.

In summary, a general fitness assessment can:

1. Assessing overall fitness can illuminate “holes” in the athlete’s training foundation.
2. Provide focus for early training phases
3. Allow for appropriate goal setting, especially in the early phases of the training program
4. Provide motivation
5. Serve as a stepping stone to more advanced testing and training

Thanks for reading