How the LESS Test Reveals ACL Injury Risk in Athletes

The main question this episode answers is: What is the LESS (Landing Error Scoring System) test, and how can fitness professionals use its research-based assessment to reduce ACL injury risk in clients, especially when considering anticipated versus unanticipated movement? The LESS test is a movement assessment that helps identify lower extremity dysfunction and ACL injury risk by evaluating how clients land from a jump, whether they know what to expect (anticipated) or are reacting to new stimuli (unanticipated).

NASM experts Wendy Batts and Marty Miller break down recent, peer-reviewed NASM research from the open-access Journal of Fitness, Wellness, and Human Performance to demonstrate how to accurately use the LESS test with athletes and everyday clients. This “Master Instructor Roundtable” guides listeners through the test’s setup, scoring system, practical applications, and the science supporting both anticipated and unanticipated testing situations. Listeners will learn how to integrate this assessment safely, score it correctly using video, and interpret results to inform program design that decreases ACL and other lower limb injury risks.

By the end of the episode, fitness professionals will be equipped to decide when and how to use the LESS test and adapt their programs for better, safer movement performance.

Chapters:

00:00:05 What is the LESS test and why is it important for injury risk?00:01:43 How does the LESS assess lower extremity function for athletes and non-athletes?

00:03:12 Why is power training and assessment needed for all clients?00:05:18 How is the LESS test set up and what exactly does it measure?00:08:13 What are the preconditions for using the LESS safely and effectively?

00:09:05 Who developed and validated the LESS and what is its research foundation?

00:14:55 What is the difference between anticipated and unanticipated LESS testing?

00:16:30 How does the LESS test scoring system work and what do scores mean?

00:22:31 Why does unanticipated movement increase ACL injury risk according to the research?

00:26:38 How can trainers use LESS results to design better injury-prevention programs?

00:33:59 What practical strategies can I use to apply LESS research in my client sessions?