Isometric Mid Thigh Pull Test

What is the Isometric Mid Thigh Pull Test?

The isometric mid-thigh pull (IMTP) test is a strength assessment tool used to measure maximal strength and the rate of force development (RFD) in athletes. The IMTP test involves the athlete standing on a force plate, gripping the bar, and exerting maximal effort to pull against the bar. This test evaluates an athlete's ability to generate force by having them pull against an immovable bar positioned at mid-thigh height. It is particularly useful for assessing overall body power, crucial for sports requiring explosive strength and rapid force generation, such as rugby, weightlifting, and track and field.

The reliability of the IMTP test is high, with intraclass correlation coefficients (ICCs) for peak force ranging from 0.73 to 0.99, with a median ICC of 0.96. Additionally, the coefficient of variation (CV) for peak force ranges from 0.7% to 11.1%, with a median CV of 4.9%. These values indicate excellent to good reliability, making the IMTP a reliable method for measuring force output and monitoring an athlete's development and performance over time.

Importance of the Isometric Mid Thigh Pull Test

This test helps identify strengths and weaknesses in an athlete's performance, guiding training and conditioning programs. It provides insights into their maximal strength and RFD, which are key indicators of overall athletic performance. The outcome of the IMPT test can also be used in conjunction with the results of a countermovement jump test to calculate the dynamic strength index (DSI) and for force-velocity profiling.

Insight from the IMTP test allows coaches and personal trainers to tailor strength training programs to enhance specific areas, improve overall strength, and reduce the risk of injury.

How to perform the Isometric Mid Thigh Pull Test

Performing the Isometric Midthigh Pull Test requires specific equipment accurately measure force production capabilities. The necessary equipment includes force plates to measure ground reaction forces and an immovable barbell, set at mid-thigh height for maximum force production. It is highly recommended to let the athlete use an alternating grip or wrist straps so that grip strength does not limit the results.

Steps to Perform the IMTP Test

Before the test, allow the athlete to warm up adequately. Following the warm-up, let the athlete perform 2-3 practice trials at submaximal effort (e.g., 50-75% perceived max) to get accustomed to the testing procedures and body positioning. After these practice attempts, the athlete will perform 2-3 maximal effort IMTP trials, each lasting 3-5 seconds. Ensure there is adequate rest (2-5 minutes) between maximal trials to allow for full recovery and reduce injury risk.

Here are the steps to doing the test:

1. Download the template from the Carepatron app or use the link under this section.
2. Adjust the bar height to the athlete's mid-thigh.
3. The athlete grips the bar with a clean grip or alternating grip.
4. The athlete stands with feet shoulder-width apart on a force plate. Ensure the knee angle is between 125-145° and the hip angle is 140-150°.
5. The athlete removes slack from the bar without pre-tensing.
6. On command, the athlete pushes their feet into the ground with as much force and speed as possible for 3-5 seconds. The athlete remains still until each trial is saved.
7. Repeat steps 5-6 for 2-3 maximal effort trials. The best result is used for comparison with normative data.

Data and analysis of the Isometric Mid Thigh Pull Test

The isometric test measures various outcomes to assess an athlete’s force generation capabilities. These outcomes include peak force (PF), rate of force development (RFD), time to peak force, and relative force. Peak force is the highest force output recorded during the test. RFD evaluates how quickly force is developed, typically analyzed in 50-250 ms (millisecond) windows. Time to peak force is the duration taken to reach the highest force, and relative force is the force output normalized to the athlete’s body mass.

The baseline data available for rugby players provide a reference for interpreting results (Martin & Beckham, 2020):

• Youth: 1162–2374 N
• Academy: 1855–3104 N
• Professional: 2254–3851 N

Due to the focus of research on rugby players, normative data for other populations are limited. The focus on rugby is beacuse overall body power is more critical in sports like rugby compared to other sports where specific skill sets or agility might be prioritized. Nevertheless, the IMTP can be performed for athletes across various sports.

Benefits of using our template

Using our Isometric Mid Thigh Pull Test template offers several advantages that streamline the testing process and enhance data accuracy.

• Standardized testing: Our template ensures that every test follows the same procedure, promoting consistency and reliability in results.
• Easy training for staff: The clear, step-by-step instructions make it simple for healthcare professionals to train new staff members on how to administer the test effectively.
• Clear documentation: The template provides designated fields for recording all necessary data, ensuring that test results are documented comprehensively and accurately.
• Digital access and customization: Available through the Carepatron app, the template is easily accessible and customizable to fit the specific needs of different testing environments and populations.

These benefits contribute to a more efficient and reliable testing process, ultimately supporting better athlete assessment and development.

Reference

Martin, E. A., & Beckham, G. K. (2020). Isometric mid-thigh pull performance in rugby players: A systematic literature review. Journal of Functional Morphology and Kinesiology, 5(4), 91. https://doi.org/10.3390/jfmk5040091