The Effectiveness of a Coach-Focused Intervention on Preventing Knee Injuries in Amateur Football Players

The Effectiveness of a Coach-Focused Intervention on Preventing Acute Severe Knee Injuries in Amateur Football Players: A Cluster Randomized Superiority Trial

The goal of this clinical trial is to find out if a coach-focused intervention can help prevent sudden-onset, severe knee injuries in youth and senior amateur football players. The main question it aims to answer is:

Does a coach-focused intervention reduce the number of sudden-onset, severe knee injuries? Researchers will compare a coach-focused intervention, designed to help coaches to use effective injury prevention training, to usual football practice to see if the intervention can prevent sudden-onset, severe knee injuries in football players.

Participants will:

Either receive weekly information and motivation on effective injury prevention training or continue their usual football practice for 14 weeks.

All will receive a weekly text message with a survey link to report any sudden-onset knee injuries among their players for 18 weeks.

Study Overview

• Status: Completed
• Conditions: Knee Injuries
• Intervention / Treatment: Behavioral: Ahead of the Game; Other: Usual Practice

• Study Type: Interventional
• Enrollment (Actual): 320
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Frederiksberg, Denmark, 2000
    • The Parker Institute

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Coach or manager at Danish amateur football teams at levels from under 14 (U14) years to senior teams.
2. Minimum 18 years of age.
3. Access to a mobile phone and computer.

Exclusion Criteria:

1. Limited Danish language skills, which prevents full understanding of the provided material and questionnaires.
2. Affiliation to teams playing under a license ranking by the Danish Football Association where training by a physical trainer is required according to the license criteria of the Danish Football Association).
3. Affiliation solely with old boys'/girls' teams (where the players have to be aged 32 and 29 , respectively, in the current season ).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Injury prevention training; Evidence-based injury prevention training programs and exercises will be send weekly to participants in the intervention arm. Additionally, participants in the intervention arm will be encouraged to access a study specific online platform containing information, inspiration, pep-talks and posters on injury prevention training.	Behavioral: Ahead of the Game; Evidence-based injury prevention training programs and exercises will be send weekly to participants in the intervention arm. Additionally, participants in the intervention arm will be encouraged to access a study specific online platform containing information, inspiration, pep-talks and posters on injury prevention training.
Active Comparator: Usual practice; Usual training	Other: Usual Practice; Usual training

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The incidence of acute severe knee injuries in players.	The difference in incidence of acute severe knee injuries (>28 time-loss days from training and matches) per 1000 hours of player exposure in players belonging to coaches in the intervention group compared with players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of acute knee injuries	The difference in incidence of all acute knee injuries (from minimal (1-3 days lost) to severe (>28 time-loss days from training or match)) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Incidence of acute minimal knee injuries	The difference in incidence of acute minimal knee injuries (1-3 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Incidence of acute mild knee injuries	The difference in incidence of acute mild knee injuries (4-7 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Incidence of acute moderate knee injuries	The difference in incidence of acute moderate knee injuries (8-28 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Time-loss days of acute knee injuries	The difference in burden of all acute knee injuries (the total number of time loss days from minimal (1-3 time-loss days) to severe (>28 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Time-loss days of acute minimal knee injuries	The difference in burden of acute minimal knee injuries (1-3 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Time-loss days of acute mild knee injuries	The difference in burden of acute mild knee injuries (4-7 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Time-loss days of acute moderate knee injuries	The difference in burden of acute moderate knee injuries (8-28 time-loss days from training or match) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.
Time-loss days of acute severe knee injuries	The difference in burden of acute and severe knee injuries (> 28 time-loss days from training or matches) per 1000 hours of player exposure in players belonging to coaches in the intervention group versus players belonging to coaches in the control group (usual practice) throughout the intervention period.	From baseline to end of the intervention, 14 weeks after baseline.

Collaborators and Investigators

• Sponsor: Marius Henriksen
• Collaborators: University of Copenhagen
• Investigators: Study Chair: Elisabeth Bandak, PhD, The Parker Institute

Study record dates

Study Major Dates

• Study Start (Actual): February 23, 2025
• Primary Completion (Actual): June 30, 2025
• Study Completion (Actual): June 30, 2025

Study Registration Dates

• First Submitted: February 11, 2025
• First Submitted That Met QC Criteria: February 20, 2025
• First Posted (Actual): February 25, 2025

Study Record Updates

• Last Update Posted (Actual): August 12, 2025
• Last Update Submitted That Met QC Criteria: August 6, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: football; knee injury; injury prevention training; coaches; players
• Additional Relevant MeSH Terms: Leg Injuries; Wounds and Injuries; Knee Injuries
• Other Study ID Numbers: APPI2-MSK-2025-KNIPS_2.0

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: IPD can upon rasonable request to the investigator be shared.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No