Hamstring eccentric strengthening program

Schache et al 11 were fortunate to record a hamstring strain injury during a sprinting trial and confirmed that the injury most likely occurs around this point in the gait cycle. Given the high rate of reinjury, it is essential for an athlete who sustains a primary hamstring strain to undergo a formal rehabilitation program before returning to his or her preinjury level of sports.

At our institution, we utilize a three-phase, evidence-based rehabilitation program and a battery of tests before clearing an athlete for full sports participation. This program is rooted in the basic science of muscle injury and treatment methods validated in previous clinical studies. A comprehensive description of our rehabilitation program was published recently by Schmitt et al. Figure 1: The Nordic hamstring exercise. Prevention of hamstring strains in elite soccer: an intervention study.

Scand J Med Sci Sports ;18[1] The athlete may present with significant pain, discoloration, and gait deviations. Use of therapeutic modalities eg, ice, electric stimulation, pulsed therapeutic ultrasound and manual soft tissue mobilization may be started immediately after the injury and can be effective for pain modulation.

If a significant gait deviation is observed, then use of crutches for ambulation is recommended. Experimental evidence suggests that active mobilization after muscle injury results in superior histochemical and biomechanical recovery compared to immobilization, 14 and riding on a stationary bike is effective for encouraging early active motion.

Progressive introduction of tension in the injured muscle is believed to strengthen the scar between fractured muscle fibers and help approximate the fiber stumps. The objectives of this second phase are to increase isotonic hamstring strength throughout the range of motion and to improve neuromuscular control of the lower extremity in preparation for sport-specific movements.

Appropriate exercises in this phase include isotonic hamstring curls, deadlifts, single-leg deadlifts, Nordic hamstring exercises, 6,13 as well as other eccentric-biased exercises, such as the L-protocol exercises described by Askling et al. The third phase of rehabilitation involves sport-specific drills and lengthened-state eccentric exercises.

The sport-specific drills may consist of sprints, agility drills, and plyometric training. The eccentric-biased exercises are progressed to performing them in positions where the hamstrings are under maximal tension. This lengthened-state method of eccentric training is thought to strengthen the hamstrings in their longer muscle length and contribute to reduction in incidence of recurrent hamstring strains.

Figure 2: Four eccentrically biased exercises studied by Orishimo and McHugh. The hip extension, Diver, and Slider exercises were adapted from Askling et al. A rep was completed when the subject lowered his or her body to the floor and then returned to the starting position by sliding both feet into full knee flexion, then assuming the bridge position and lifting one leg off the floor.

Once the athlete has completed all three phases of the rehabilitation program without pain or compensatory patterns, a battery of tests are carried out to ensure the athlete can safely return to full sport participation.

Strength testing of the hamstrings is performed with an isokinetic or hand-held dynamometer and compared with the noninjured side. A manual muscle test may be performed in the prone or supine position if a dynamometer is not available.

Recently, a rigorous functional test, named the H-test, has been proposed as a tool to determine safety in returning to sports after hamstring injury. Once an athlete has been cleared to return to sport participation, we recommend incorporating the eccentric exercises eg, Nordic hamstring exercise, L-protocol, etc into his or her strength and conditioning routine, as these exercises have been shown to reduce recurrence of hamstring strains. Eccentric exercises have been shown to add sarcomeres in series 18 and increase muscle strength at longer lengths ie, the descending limb of the length-tension curve.

Studies by Kilgallon et al 20 and Mjolsnes et al 21 have compared the effects of eccentric versus concentric hamstring strengthening exercises and showed that increases in strength at longer muscle lengths occur only after bouts of eccentric exercises. Therefore, training the hamstrings eccentrically may give them the ability to resist the high forces experienced during high-speed running and to avoid disruption of the muscle fibers.

A popular and highly effective eccentric exercise for the prevention of hamstring strains is the Nordic hamstring exercise NHE. To perform this exercise, the athlete starts in an upright kneeling position with arms at the sides and a partner holding the ankles on the ground. From this position, the athlete falls forward and, as slowly as possible, lowers the torso to the ground using only the hamstrings. In the end position, the athlete is lying prone on the ground with straight knees, hips, and torso Figure 1.

The athlete then returns to the starting position by pushing up with the hands while using minimal concentric contractions of the hamstrings. Brockett et al 22 demonstrated that a single bout of the NHE 12 sets of six repetitions produced a shift in the angle of peak torque toward longer muscle lengths.

Additionally, this adaptation was shown to have a long-lasting protective effect against subsequent muscle damage. Although the NHE has been shown to be very effective in preventing hamstring strains, it does have a few limitations.

First, a partner is needed to hold the ankles while the athlete performs the exercise. While this may work well in a team setting, it may not be suitable in a rehabilitation or home exercise program. Secondly, the NHE is a bilateral exercise ie, performed on both legs simultaneously. This could allow for one side to compensate for the other and to further reinforce side-to-side strength imbalances in patients rehabilitating a hamstring strain.

These limitations have led researchers to investigate alternative eccentric exercises that are just as effective in preventing injury.

All three exercises in the L-protocol the Extender, the Diver, and the Glider were simple unilateral eccentric exercises that participants performed using minimal equipment and the weight of their body as resistance. Additionally, there were no reinjuries during the one-year follow-up period in the eccentric training group, compared with two in the conventional exercise group.

The same authors found similar results in sprinters and jumpers using the L-protocol compared with conventional strengthening and stretching. To further understand the underlying causes of these clinical results, Orishimo and McHugh 26 investigated the effects of an eccentrically biased exercise program inspired by the L-protocol on the angle-torque relationship of the knee flexors in 12 healthy individuals. A secondary objective was to characterize the electromyographic activity of the hamstrings during each of the four exercises Figure 2.

Although these exercises were considered eccentrically biased, electromyographic data showed substantial hamstring activity during the concentric portions of the exercises, as well. The effect of Nordic hamstring exercise training volume on biceps femoris long head architectural adaptation. Injury rate and prevention in elite football: let us first search within our own hearts [published online ahead of print June 02, ].

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Neuromuscular adaptations to isoload versus isokinetic eccentric resistance training. Each training set consisted in 4 repetitions of the Nordic hamstring exercise and 6 repetitions of the bilateral stiff-leg deadlift. Conclusion: Low-volume knee-flexor eccentric training is as effective as a greater training dose to substantially improve knee-flexor strength and fascicle length in-season in young elite soccer players.

Low-volume is however likely more appropriate to be used in an elite team facing congested schedules. Your email address will not be published. Featured Posts. Full text here Abstract Aim: To compare the effect of low- vs.