Posts in prevention
Higher Intensity Exercise Leads to Greater Disease Risk Reductions

Colorado remains one of the fittest states in the Colorado with low rates of obesity, diabetes, heart disease, and other diseases associated with low activity levels.  Specifically, our home town of Boulder remains of the fittest cities in the country due to its' high percentage of citizens who meet or exceed the U.S. Surgeon General's recommendations on daily exercise.  

A MET minute is the intensity of the exercise multiplied by its' duration.  For example, light exercise is 1-3 METs where as vigorous activity is 6 or greater METs.  600 MET minutes per week could be either long duration light to moderate activity or a lesser duration of high intensity exercise.  These established guidelines were based off of epidemiological research showing the positive impact of aerobic exercise on risk reduction for many diseases including stroke, heart disease, diabetes, and cancer.   New research is now showing a further reduction in disease risk if individuals exceed these weekly guidelines by exercising longer and harder.  

A recent review article in the British Medical Journal quantified the dose response of exercise duration and intensity on disease risk modification (Kyu et al. 2016).  The authors reviewed 174 articles on exercise's impact on disease.  In general, the authors found more active participants were at lower risk of many diseases (see above), but those were more active showed even greater reductions in disease risk.  Thus, it appears there is further benefit to exercising at a higher intensity and/or longer duration to further reduce disease risk.  Individuals are advised to speak with their Physician and Physical Therapist before engaging in any vigorous exercise program. 


Risk Factors for Knee Injuries in Adolescents and Teenagers

The knee is one of most commonly injured areas among our Boulder County student athletes.  Injuries range from the traumatic (ligament tears) to overuse (tendonitis) across a variety of indoor and outdoor sports.  Prior research has shown overuse injuries to be the most common knee injury affecting our student athletes but data regarding the risk factors for these two types of injuries has been limited.  

Recently a large study was conducted to document sports participation, injuries, and pain levels of over 1300 8-15 year old children (Junge et al. Med Sci Sp Ex. 2016).  The authors documented the frequency, severity, and type of knee injuries within this group in order to determine the risk factors associated with these injuries.  The authors reported 952 knee injuries (85% overuse) were sustained by the athletes in the study.  Participation in gymnastics was the greatest risk factor for traumatic knee injury.  

Within the overuse injury category female sex, prior knee injury, and a higher frequency of practices and games per week were associated with a higher risk of injury.  The majority of these overuse conditions were self limiting in nature and are successfully managed with conservative care including Physical Therapy.  To learn more on now to reduce your child's risk of knee injury contact your local Physical Therapist. 

Risk Factors for Ankle Sprain

Ankle sprains are one of the most common sports and orthopedic injuries encountered in Physical Therapy.  In previous blog posts we described the effectiveness of Physical Therapy treatments over other treatments including rest, ice, compression, and elevation (R.I.C.E.).  In addition, we have good evidence supporting the use of Physical Therapy clinical testing to determine which sprains are most likely to develop into chronic symptoms.  A recent review article highlighted the modifiable risk factors, which make patients more likely to sustain a first ankle sprain. 

Authors in the journal Sports Health (Kobayashi et al. 2016) reviewed 8 published articles to determine the ability of risk factors to predict a future ankle sprain.  The authors reported patients have a greater risk of ankle injury with increased weight, weakness in the leg and ankle musculature and limited balance ability.   Recreational and professional athletes are advised to work with a local Physical Therapist to identify and treat these impairments to reduce their risk of future injury.

The Impact of Core and Leg Muscle Fatigue on Baseball Throwing Mechanics

As we move into Spring we begin to see our youth athletes return to the baseball diamond often with a sudden increase in practice volume.  The sudden increase in throwing volume, either in the field or on the mound, places the athlete's shoulder and elbow at greater risk of baseball injuries. The greatest risk factors for injury include throwing more than 80 pitches/game, playing baseball greater than 8 months/year, and pitching with arm fatigue. As discussed in our prior posts, an athlete's throwing velocity is driven by their legs strength and power. Athletes with leg weakness are more likely to suffer from progressive changes in performance and increased injury risks.

A recent study in the Orthopedic Journal of Sports Medicine authors analyzed the impact of fatigue on throwing velocity, accuracy, and throwing mechanics (Chalmers et al. 2016). Authors studied 28 elite adolescent (13-16 year old) pitchers as they pitched a simulated game (90 pitches). Each pitch was analyzed for velocity and accuracy while every 15th pitch was analyzed for pitching mechanics. As expected the velocity, accuracy, and mechanics suffered with increased pitch counts. Importantly, the authors showed the loss of velocity, accuracy, and biomechanics were preceded first by core and leg muscle fatigue.

This study adds to the importance of controlling pitch counts and treating the lower extremities in order to improve throwing performance and reduce injury risk.  

Marathon Running Injuries

Marathon running is a challenging event requiring substantial amounts of endurance and strength training for optimal performance and injury prevention.  The race distance of 26.2 miles requires high mileage training, often >75-100 miles per week at the elite level, placing the athlete at risk of a running related injury (Saragiotto et al. 2014).  In addition to training volume, athletes with training errors (too much volume too quickly), muscle imbalances, and gait deviations place themselves at greater risk of future injury and lost performance.    

A recent study in the International Journal of Sports Physical Therapy (Carvalho et al. 2016) sought to document the frequency, severity, and location of running related injuries among elite marathoners.  The athletes all met the following criteria: sub 2:35 and 3:00 marathon for men and women, respectively, as well as, enrollment in the "elite" racing category.  The 199 enrolled athletes were asked to assess their prevalence of running injuries over the previous 12 months.  Even at the elite level, 3 out of 4 runners reported a running related injury most commonly experienced in the leg (19%), knee (15%), and achilles (15%).  Among the injured runners close to 40% described at least two different injuries over the last year.  

Athletes preparing for an upcoming marathon are encouraged to work with a local Physical Therapist to reduce modifiable risk factors for running related injuries. 

Sports Specialization and Injury Risk

With a changing in the seasons we also see a changing of the sports in our Boulder County student athletes.  Athletes previously focused on winter sports including swimming and basketball are now able to focus on spring sports including baseball and track.  Prior research shows athletes who change sports during the sports year have half the risk of injury compared to their peers who focus on one sport all year round.  Early sports specialization  in school sports places athletes at greater risk of overuse injuries during their seasons due to lack of recovery/rest periods, muscle imbalances, and repetitive sports movements such as pitching.  

A recent article in the American Journal of Sports Medicine adds further support to the risk of student athletes playing one sport year round.  Bell and colleagues studied over 300 athletes aged 13-18 from 2 high schools to determine the prevalence and impact of year round athletics (2016).  Athletes were classified in 3 groups including low, moderate, and high specialization based on their single sport participation.  Not surprisingly, athletes from larger high schools were more likely to specialize in one sport and these athletes reported greater rates of overuse injuries than their peers who played at smaller schools or multiple sports per year. Specifically, athletes playing one sport greater than 8 months per year were at greater risk of injury than athletes who participated in one sport less than 8 months of the year.  

Parents, coaches, and student athletes are advised to consider the risk of spending >75% of the year training for an individual sport.  Coaches and athletes are advised to schedule their training year based on periods of dedicated to both training and recovery.