There are pros and cons to performing frequent performance testing in athletes throughout the competitive season.
- Coaches can determine if strength and power are increasing, decreasing or staying the same. This can inform coaches of the effectiveness of their program and help drive in-season program design. Furthermore, it can lead to further investigation by the coach to determine if performance decrements are the result of fatigue accumulation, minor injuries or simply because the athletes are getting weaker.
- Performance testing is time consuming and often fatiguing. For example, fitness testing throughout the in-season may contribute to fatigue and put athletes at risk of injury due to the high exertion levels of common field tests (e.g., YoYo-IRT1). Maximal sprinting and agility tests come with the risk of hamstring strain and rolled ankles.
In order to reap the benefits of frequent testing without the added time demand and risk of injury, many coaches are resorting to non-fatiguing performance tests for key performance indicators. One performance evaluation that is gaining popularity among teams is the isometric mid-thigh pull. This is performed on force plates so that peak force and rate of force development markers can be derived.
A new study published ahead of print in the Journal of Strength and Conditioning Research evaluated relationships between common performance tests and isometric mid-thigh pull parameters in a team of collegiate rugby players (n=15). The team was put through a variety of performance tests including 1RM squat, 40 m sprint with 5 and 10 m splits, T-test and pro-agility. Correlations were performed for each performance test and rate of force development and peak force production at various time intervals (e.g., 30 ms, 50 ms, 90 ms, 100 ms, 150 ms, 200 ms and 250 ms).
The results showed that peak force output correlated very strongly with 1RM squat (r = 0.87) but did not significantly relate with any other performance variable. Rate of force development correlated strongest with 1RM squat at 250 ms (r = 0.75); with pro agility at peak – 90 ms (r = 0.53); and with 0-5 m sprint time at peak – 50 ms (r range from 0.53 – 0.57). Based on these results, it appears that the isometric mid-thigh pull may be a suitable alternative to 1RM squat testing based on the very large correlation. It may also be useful for predicting agility and acceleration performance although this correlation wasn’t quite as strong. As force plates are becoming more affordable and user-friendly, don’t be surprised to see more teams using them for routine athlete monitoring in place of traditional performance tests.
Wang et al. (2016) Isometric Mid-Thigh Pull Correlates with Strength, Sprint and Agility Performance in Collegiate Rugby Union Players, Journal of Strength and Conditioning Research, In press.