Hamstring strains are a common injury for athletes in sports that have to sprint. One of the interventions to help prevent these injuries is the Nordic hamstring exercise. With this exercise, the athlete kneels and has their ankles restrained. Then, keeping their upper body as straight as possible, they lower their upper body to the ground resisting it by using their hamstrings.
The intent behind the exercise is to increase isometric and eccentric strength of the hamstrings as well as the length of the hamstring fascicles. This exercise is now widely employed in attempts to prevent hamstring injuries. There are two challenges with this. The first is that hamstring injuries are not decreasing. The second challenge is that athletes are not complying with training programs that use the Nordic hamstring exercise.
With this in mind, Cuthbert et al performed a meta analysis to look at the use of the Nordic hamstring exercise. The thought behind the study was to see if athletes aren’t complying with the programs due to the volume being too high (i.e. a high volume of eccentric exercise can mean a lot of post-exercise soreness). The authors wanted to determine if there was a minimum effective dosage of the exercise.
In their review, the authors did not find a relationship between volume and relative eccentric peak torque, eccentric peak torque, or eccentric force. Both high volume and low volume sessions involved increases. The authors looked at studies that included a little more than 20 repetitions per week and the way to more than 70 per week. They did find that 6 weeks of training was the minimum intervention duration for a training effect.
Most of the studies involved a progress increase in the training volume, though this also resulted in challenges with compliance. The authors did notice that two studies in their review included periods of four weeks or longer where the volume on the exercise did not change, but the intensity of the exercise may have increased allowing for the program to be effective. By the intensity of the exercise it means that the hamstrings became stronger so they “failed” with the upper body closer to the ground.
The first thing to point out here is that there are no magic exercises. By this I mean that simply adding one exercise to a program isn’t going to change everything and dramatically reduce hamstring injuries – it’s more complicated than that. I’ve discussed this previously.
The Nordic hamstring exercise is a mainstay in soccer conditioning programs for preventing hamstring strains. Due to its eccentric nature it can make athletes quite sore, which can make compliance with the training program challenging. If lower training volumes can be beneficial, this would mean less soreness, which would mean better compliance with the program.
The idea of increasing the intensity by strengthening the hamstrings and making the “failure” point closer to the ground is interesting and makes a lot of sense. However, this is difficult in a large group coaching situation where some athletes won’t give as much effort as they need to make the exercise beneficial.
The Nordic hamstring exercise does not require a lot of equipment, training, or space. This makes it friendly to athletic programs. However, getting the most from the exercise requires an amount of will that many athletes (especially in large coaching situations like high school sports) may not be desiring to apply, which then results in seriously impaired gains from training. I could see this exercise being a lot more beneficial in small group/one-on-one coaching situations.
Cuthbert, M., Ripley, N., McMahon, J.J., Evans, M., Haff, G.G., and Comfort, P. (2020). The effect of Nordic hamstring exercise intervention volume on eccentric strength and muscle architecture adaptations: A systematic review and meta-analyses. Sports Medicine, 50, 83-99.
