Related Experiment Video
Updated: May 16, 2025

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
Four-week Nordic hamstring exercise intervention for individuals with ACL reconstruction via hamstrings tendon
Grant E Norte1,2, Neal R Glaviano3, David A Sherman4,5
1Cognition, Neuroplasticity, & Sarcopenia (CNS) Laboratory, Institute of Exercise Physiology and Rehabilitation Science, University of Central Florida, Orlando, FL, USA. grant.norte@ucf.edu.
Background:
The Nordic hamstring exercise (NHE) has been widely used among uninjured, athletic populations to mitigate the risk of hamstring injury, yet little is known about its utility as an intervention for individuals who undergo ACL reconstruction with hamstring tendon autograft (ACLR-HT). Understanding the feasibility of NHE as a means of enhancing hamstring function may aid in the development of evidence-based recommendations to guide hamstring recovery. Our aim was to determine the feasibility of conducting a pilot NHE trial among individuals with ACLR-HT.
Methods:
We used a single-blind randomized controlled trial with parallel arms to investigate individuals 18-35 years with primary, unilateral ACLR-HT. Twenty-three participants were randomized to a standardized, 4-week (10 session) progressive NHE intervention (n = 17) or usual care control (n = 6) group at a 3:1 ratio. Those randomized to the control group were eligible to open-enroll in the intervention group at the completion of the original study period. Primary feasibility outcomes included recruitment uptake, protocol adherence, dose goal attainment, and retention. Exercise perceptions and safety were also assessed. Summary statistics were used to descriptively report all findings.
Results:
Two control participants were open-enrolled in the intervention group after completing their original study period (n = 19). All participants (88.5% recruitment uptake) adhered to the exercise protocol (100%) and 18 participants (94.7%) attained the total exercise dosage goal. A 100% retention rate was observed, as all participants (intervention 17 randomized, 2 open-enrolled; control 6) returned for their follow-up assessment.
Conclusions:
A standardized, 4-week progressive NHE protocol is feasible for individuals with ACLR-HT. Positive perceptions of exercise, minimal exercise-related discomfort, and no reported adverse events further support the acceptability of this protocol and the likelihood of successful implementation in future efficacy trials.
Trial Registration:
ClinicalTrials.gov, NCT05738200. Registered 2 November 2022-retrospectively registered, https://clinicaltrials.gov/study/NCT05738200 .
More Related Videos
05:07Author Spotlight: Implementing the Enhanced Recovery After Surgery Concept in Rehabilitation Following Anterior Cruciate Ligament Reconstruction
Published on: March 1, 2024
08:30Surgical Retrieval, Isolation and In vitro Expansion of Human Anterior Cruciate Ligament-derived Cells for Tissue Engineering Applications
Published on: April 30, 2014