Hamstring Injuries- How to Prevent Them

Man stretching his hamstring muscles to prevent injury- may not be the best option. Apr14th 2020

The Most Effective Exercises for Strengthening and Preventing Injury in the Hamstring!

Hamstring Injuries

Hamstring injuries have been the bane of many athlete’s existence, because the lightlihood of reinsuring is high. They are also often extremely painful in the initial phase. These injuries occur very frequently in most sports, especially those when rapidly taking off or stopping. Every year we see several big-name athletes suffer from a “nagging” hamstring injury.

At times, it seems these athletes are plagued by these hamstring symptoms throughout their entire career. Therefore, it is important to narrow in on the best exercises that strengthen the hamstrings in order to prevent initial injury and repeated injury. And, improving overall hamstring strength is critical. 

When does the hamstring injury happen?

In order to understand the how sprains happen during sprinting, it is important to understand the running cycle.

For these purposes, this cycle can be divided into two phases: the stance phase and the swing phase.

When the toe of the stance leg leaves the ground, the swing phase begins. When the foot makes contact again, we reenter the stance phase.

The most common window for a strain is during the end of the swing phase and the beginning of the stance phase. This window can be narrowed even further to the end of the swing phase. During this part of the running cycle, there are several repeated eccentric contractions that can strain/damage the hamstrings. Also, peak force on the hamstring is reached, and the muscles of the hamstring are placed under a great stretch [1]. The combination of these factors creates a higher chance of injury to the hamstring, especially if the muscles aren’t strong enough.  

Proper training

As mentioned before, the greatest chance of injury is during the end of the swing phase. During this time there are repetitive and heavy eccentric forces on the muscles. Therefore, it’s important to train the hamstrings for that force. With this concept in mind, one study proposes that “the focus should be on high-load eccentric contractions at the knee joint and to keep the hip in a large flexion position (80°) in order to reach a greater “elongation stress” than in the terminal swing [1].” The same study suggests these three strengthening exercises: the Nordic hamstring exercise, the eccentric box drop, and the single leg deadlift. These exercises have eccentric contractions, high loads, and slow to moderate angular velocity; all of which are important for preventing injury of the hamstring . One important part to note is the section about hip position and the importance of hip flexion during the exercises. Both the eccentric box drop and the single leg deadlift require hip flexion; however, the Nordic hamstring exercise does not. A second study corroborates the lack of hip flexion during the Nordic hamstring exercise as a fault to the exercise. While it is still a very effective exercise at specifically strengthening the short head of the biceps femoris, it is less effective when compared to other strengthening exercises that incorporate hip flexion at strengthening the long head of the biceps femoris as well as the semimembranosus [2].  

Conclusion

The Nordic hamstring exercise, eccentric box drop, and single leg deadlift are all effective exercises at improving hamstring strength and preventing hamstring injury. It is important to note that these are not the only exercises and may not even be the best at strengthening this area. However, these exercises are an example of exercises that have the eccentric activity, low angular velocity, and high load needed in order to achieve the therapist’s and patient’s treatment goals. 

If you need assistance strengthening you hamstrings set up an appointment with one of our skilled sports physical therapists.

References:

[1] https://link.springer.com/article/10.1007/s40279-013-0097-y 

[2] https://oce.ovid.com/article/00124278-201312000-00025/HTML 

Credit:

Jed Meyers and the media team.