Monitoring and measuring the strength of hamstrings can provide valuable insights for sports science practitioners. This post focuses on assessing hamstring strength during an eccentric movement using VALD's NordBord and the Nordic Hamstring Exercise.
The hamstring muscle group plays a vital role in various athletic movements, including sprinting, jumping, and changing direction. Strong hamstrings contribute to better performance and help mitigate the risk of injuries, particularly strains that are common in many sports.
Several tools, like isokinetic dynamometers, handheld dynamometers, fixed frame dynamometers, and force places like VALD's ForceDecks, exist to monitor different aspects of hamstring strength. In this post, we focus on assessing eccentric hamstring strength using the NordBord.
To illustrate how the NordBord assesses hamstring strength capacities, watch the video below from the Global Performance Insights YouTube channel, which is part of our sports science athlete testing series in collaboration with VALD Performance.
The NordBord System for Hamstring Strength Testing
The NordBord by VALD Performance is a specialised device designed to measure eccentric hamstring strength. Here's a detailed look at the testing process:
Setup and Positioning
Athletes kneel on the NordBord with their heels secured under the ankle hooks. It's crucial that athletes do not use their toes to grip the board to leverage their strength.
The ankle hooks should be positioned at the top of the shoes, perpendicular to the leg, ensuring consistency in each test.
Testing Protocol
Athletes maintain an upright body position with neutral hips, focusing on increasing the knee angle while lowering their body. This emphasises the eccentric contraction of the hamstrings.
Athletes catch themselves with their hands at the bottom of the movement and push back up as the concentric phase is not measured.
Typically, three to six trials are conducted, sometimes split into two sets depending on the day's programme.
Data Collection and Analysis
The NordBord system provides real-time feedback on the force measured through the ankle hooks during the Nordic Hamstring Exercise.
This data helps assess eccentric hamstring strength levels across athletes and track any asymmetries between the left and right sides.
Body mass normalisation can be essential, especially in sports with varied body compositions, like American football or youth athletes (see the video above for further information on this research).
Considerations and Limitations
While the NordBord provides valuable insights into eccentric hamstring strength, it only represents strength in a knee-dominant position. Therefore, it cannot predict injury risk in isolation. Additionally, the Nordic Hamstring Exercise can cause delayed onset muscle soreness (DOMS), particularly for those unfamiliar with it. Studies suggest that only two familiarisation sessions are needed to produce reliable data, but practitioners should consider the broader training context.
FAQs on Eccentric Hamstring Strength Testing
Why is eccentric hamstring strength important for athletes?
Eccentric hamstring strength is critical because it is critical in many athletic movements and specifically helps with a braking action during the gait cycle, particularly when sprinting. It is therefore, an important factor in hamstring injury risk as well as athletic performance.
How does the NordBord measure hamstring strength?
VALD's NordBord measures hamstring strength using force cells built into the ankle hooks. During the Nordic Hamstring Exercise the athlete kneels on the NordBord, then slowly lowers their upper body while maintaining their hip angle and increasing their knee angle. These cells capture the force exerted by the hamstrings during this eccentric movement.
Why use the NordBord to measure hamstring strength?
The NordBord is easy to use and provides immediate feedback, engaging athletes effectively. In many training environments, nordics are already part of the training programme, making it a seamless addition for strength monitoring. The device also supports various other hamstring exercises, enhancing its utility in strength training. For more on these alternative strengthening and testing exercises, see this post on other hamstring test options.
Stay tuned for more insights on strength testing in our series sponsored by VALD Performance. Subscribe to our blog to stay updated!
Found my free content useful? Say thanks here 😊: https://www.buymeacoffee.com/joclubb
This article is support by VALD Performance. For more information, about their technology, visit their website.