Posts tagged hamstring injury
Previous History of Hamstring Injury Associated With Reduced Sprint Performance
hamstring-strain-soccer-sprinting

Hamstring injuries are one of the most common injuries in both individual and team sports. In sports such as soccer and football these injuries involve a traumatic pull of the muscle while sprinting or accelerating. After the initial healing phase athletes must rehabilitate the injury with Physical Therapy exercises to regain optimal muscle function and reduce their risk for future injury. Hamstring injuries often become recurrent if strength is not normalized along the hip, knee, and ankle muscles along the back of the leg. A new article highlights how these injuries also limit performance in sprinting trials.

hamstring-injury-soccer-treatments

Roksund and colleagues studied professional soccer players and collected data on previous hamstring injuries, as well as, each athlete’s strength, flexibility, aerobic capacity, and sprint performance (Front Physiol. 2017). Of the 75 athletes included in the study, 16% sustained a hamstring strain over the previous 2 years. The previously injured athletes demonstrated a significant loss of velocity during a 40 meter sprint test, as well as, a drop in performance over repeated sprints compared to their healthy peers. Interestingly, measures of flexibility, strength, aerobic capacity, and maximum power was not significantly different between groups. Injured athletes are encouraged to work with their local Physical Therapist to accelerate their recovery from muscle strains and eventual return to sport.

Click Here to schedule your next appointment with the experts at MEND

Nordic Hamstring Exercise Shown to More Evenly Recruit Hamstring Muscles
Photo Credit: Jospt.org

Photo Credit: Jospt.org

Hamstring injuries are a common sports medicine injury treated in our Boulder Physical Therapy practice.  These injuries can be placed in two categories: acute trauma often related to sprinting and cutting movements or repetitive stress and overload to the hamstring often found in athletes with weak gluteus muscles.  In our previous blog posts, we have described the importance of gradual loading of the injured hamstring to promote an optimal healing (remodeling) response, as well as, utilizing a hamstring strengthening program to reduce the risk of future hamstring injury.  A recent article sheds light on common exercises used to strengthen the hamstring and how these different exercises target the 3 muscles which make up the hamstring.

Messer and colleagues studied the hamstrings of active women without a history of lower limb injury (JOSPT. 2018).  All participants underwent a MRI both before and after performing eccentric (lengthening) contractions of the hamstrings on both of the exercises pictured above.  Muscle activation levels were calculated based on changes between the two MRI images.  The authors reported both exercises targeted the inner (medial) hamstring muscle, but the commonly utilized nordic hamstring exercise more evenly recruited all 3 hamstring muscles.    

Contact the experts at MEND to learn more on which exercises are best for your sports or orthopedic injury

 

Hamstring Training for Sprinters
hamstring-injury-strain-pain-sprinting

Sprinting either in track or sport requires rapid, high force muscle contractions across the lower body.  If the forces utilized during the acceleration phase of running are greater than the capacity of the muscle to absorb these forces injuries can occur.  Hamstring strains in this population of runners are common due to the rapid shortening and lengthening of the contracting muscles.  We have previously written on our Physical Therapy blog on the diagnosis and treatment of these injuries, but off season and in season strengthening remains the standard of care.  Specifically, nordic hamstring curls are often prescribed for sprinting athletes but a recent research article highlights other exercises which be used for hamstring strengthening among sprinters.

photo credit: International Journal of Sports Physical Therapy

photo credit: International Journal of Sports Physical Therapy

In the International Journal of Sports Physical Therapy authors studied healthy male participants as they sprinted and performed a variety of hamstring strengthening exercises (van den Tillaar et al. 2017).  The authors measured hamstring muscle recruitment and lower body biomechanics during each of these tasks to determine which Physical Therapy exercises best represent the muscular and biomechanical demands of sprinting.  The authors report the nordic hamstring curl, as well as, the laying kick activate the hamstring muscles at a high enough level and similar joint angle to benefit sprinters' strength training programs. 

To learn more on which exercises are best for your activity contact your local Physical Therapist. 

Reducing Hamstring Strains in Sprinters
hamstring-injury-pull-strain-sprinting

Hamstring strains or pulls are a common injury among acceleration sports including rugby, soccer, and sprinting.  Our previous blogs have written about the causes and treatments of these muscle injuries.  One of the common causes of injury involves a lengthening contraction (eccentric) of the muscle during these explosive sports movements.  If the muscle is unable to handle the forces placed upon it an injury occurs.  To reduce this injury risk, researchers and clinicians have focused on improved the strength and tissue capacity of the hamstring through training.  

A long term study was reported in the Orthopedic Journal of Sports Medicine describing 3 different interventions utilized to reduce the risk of hamstring injury (Sugiura et al. 2017).  Authors assessed 3 different prevention methods in a group of top ranked collegiate and national level sprinters over a 24 year period.  The first training program utilized over a 4 year period consisted of strengthening on a leg curl machine.  During this period 16 strain injuries occurred in a group of 116 sprinters.  The staff then included hip strengthening, agility and hurdle work in addition to the leg curl.  The authors reported a 56% reduction in hamstring strains over this 9 year period.  Finally, the authors included exercises from the first two interventions as well as dynamic stretches and nordic curl training for the hamstring.  This group of close to 300 sprinters sustained only 2 strain injuries over a 12 year period, almost a 90% reduction in strain rates.  

Courtesy: bretcontreras.com

Courtesy: bretcontreras.com

This study adds to our existing evidence on the importance of of hamstring strengthening for both performance and injury prevention among sprinting athletes 

Hamstring Injuries in Runners - Risk Factors, Symptoms, Management and Prevention
running-hamstring-pain-injury-treatment

Running remains one of the most popular forms of exercise due to its’ affordability, accessibility, and health benefits.  The popularity of the sport has grown tremendously over the last few decades, but despite advancements in shoe wear, training methods, and rehabilitation interventions the injury rates remain frustratingly high.  Up to 90% of runners will report an injury in the past requiring them to miss training or competition time.  The greatest percentage of injuries are classified as overuse in nature and involve the lower extremity. 

The hamstring muscles are an essential, but often symptomatic, group of 3 muscles spanning from the pelvis to the knee.  These muscles produce the movements associated with bending the knee and bringing the thigh behind our body.   When the foot is on the ground these muscles work closely with the gluts and calf muscles to move the body forward over the foot.   In a runner, these hamstrings produce the forces necessary for the flight phase of running, as well as, assist in the deceleration of the leg in preparation for heel or foot strike.  This important function places the hamstring at risk for both overuse and traumatic injuries.

The hamstrings can be overloaded during run training due to poor running mechanics, training errors, and muscle imbalances.  Runners often present with hamstring muscle and tendon pain due to weakness in their glut musculature.  The glut muscles are the primary muscles used to produce the flight phase of running.   Without the contribution from these powerful muscles runners place increased loads on the hamstrings leading to chronic pain, tightness, and decreased running performance.  Often runners focus on soft tissue work and stretching of the hamstring when the true culprit is weakness in glut muscles. 

Traumatic hamstring strains during high-speed running activities occur at the end of the swing phase, recovery stride, as the hamstrings contract but also lengthen (eccentric contraction) in preparation for landing.  The transition from deceleration to acceleration at push off contributes to the cause of injury.  The outer most hamstring muscle, the biceps femoris, is the most injured muscle among the 3.  Injured runners often report an immediate onset of pain in the back of the thigh often preceded by a feeling of tightness or cramping.  This pain can be associated by warmth, tenderness, swelling, discoloration, and deformity depending on both the severity and location of the injury. 

In addition to these complaints, runners often present with losses of flexibility, strength, and walking or running function depending on the grade of injury.  The least severe, grade I, strain involves minimal tissue damage due to a slight stretching of the muscle fibers and has the fastest return to sport.  With greater degrees of tissue injury, runners experience greater amounts of pain and apparent signs of injury including weakness and pain upon muscle contraction.  A grade II or moderate injury involves tearing of the muscle fibers often presenting with discoloration, swelling, and deformity in the muscle.  The most severe injury, grade III, involves a complete tear or rupture of the tissue often associated with a loud pop at the time of injury.   Thankfully, these injuries are rare and are normally only seen with high speed sprinting and sports activities. 

Rehabilitation of these injuries by a licensed Physical Therapist can accelerate the healing process allowing a runner to return to sport in the most safe and effective way possible.  Depending on the severity of the tear, mild to moderate tears often return to running in weeks to months.  Grade III tears with high degrees of disability and loss of function should be evaluated by an orthopedic surgeon.   Physical Therapists are essential clinicians in the management of these injuries who often utilize interventions including joint mobilization and manipulation, dry needling, soft tissue mobilization, and most importantly exercise to quickly reduce symptoms associated with the injury. 

In the initial phases of recovery, emphasis is placed on controlling pain and inflammation, as well as, protecting the site of injury through activity modification. Depending on the grade of injury strengthening is initiated first in non-weight bearing (foot off the ground laying on stomach) with progression to weight bearing exercises as tolerated by the injured tissue.  Bridging is an excellent example of initially loading the injured tissue prior to moving into standing exercises.  Emphasis is placed on matching the strengthening exercise to the injured tissues tolerance for load.  Under-loading and over-loading the injured muscle with exercise are equally detrimental to the optimal recovery of the injured muscle.  Eccentric strengthening exercises, such as Nordic hamstring curls and deadlifts, are excellent choices to both prepare the injured tissue for the demands of running and prevent the recurrence of future injury.

Unfortunately, many sports including running report a high injury recurrence rate.  The elevated recurrence rates are influenced by clinicians and runners focusing on only the symptoms not the underlying causes of their injury.  For example, increasing both glut and hamstring strength to normative levels prior to return to sport.  Surprisingly, hamstring length, flexibility, and stretching have not been shown to significantly reduce an athlete’s risk of injury.  Conversely, strengthening and specifically eccentric or lengthening strengthening has been shown to reduce the risk of hamstring strains among athletes.  These exercises specifically train the muscle and the athlete to handle the demands of their sport.  Athletes are also encouraged to work with a licensed Physical Therapist or running coach to identify any abnormal mechanics in their running gait, which may have either precipitated or perpetuated their symptoms.

In summary, hamstring injuries are a common problem among recreational runners but injury prevention programs can mitigate the risk of injury.  Runners are advised to avoid large increases in running volume(terrain, intensity, duration, frequency) during their training cycles and to incorporate a strength training program to complement their endurance training.  Specifically, eccentric strengthening has been shown to have the greatest impact on this injury. 

The Impact of Hamstring Flexibility on Hamstring Injuries

In our prior posts on injury prevention in sports we have highlighted the importance of training volume management, balance training, and strength training.  Of all the training options, strength training is the most important due to its' ability to cut an athlete's risk of injury in half.  Despite the evidence many healthy athletes focus a large percentage of time on static stretching either before or after practice.  With time being a finite question we must ask if stretching reduces injury risk.

A large prospective study in the American Journal of Sports Medicine was conducted on the impact of hamstring flexibility on hamstring injury incidence in 450 high level amateur soccer players (Huisstede et al. 2016).  The athletes' hamstring flexibility was assessed on the sit and reach test prior to the start of the season.  The athletes were then followed for 1 year to determine the incidence of hamstring strains.  5% of the athletes sustained a hamstring injury during the season, but the authors noted no significant relationship between flexibility and risk of injury.  

Athletes are encouraged to focus their sports preparation on proven injury reduction programs involving strength training, eccentric hamstring loading, and proprioception training.