Training load management to reduce injuries in elite youth football

ISRCTN	ISRCTN18177140
DOI	https://doi.org/10.1186/ISRCTN18177140
Protocol serial number	93841844
Sponsor	Norwegian School of Sport Sciences
Funder	Oslo Sports Trauma Research Center

Submission date: 21/12/2017
Registration date: 16/02/2018
Last edited: 14/10/2020

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Injury, Occupational Diseases, Poisoning

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Background and study aims
Youth football has similar injury problems to adult football, and injuries should therefore be considered a problem. An injury to a youth footballer could be detrimental to their ambitions and even worse, make them drop out of organized sports. However, research has shown that it is possible to reduce the rate of injuries in youth football. For example, the FIFA 11+ has shown a large reduction in overall injuries. However, prevention interventions in football have to date focused almost exclusively on interventions designed to alter intrinsic modifiable risk factors, for example through a structured warm up. Although training load seems to be highly associated with injury risk, no intervention has to date investigated training load management. The aim of this study is to investigate the effect of a training load progression model on injuries in elite youth footballers.

Who can participate?
Male and female footballers aged 15-19 from one of the top three tiers in Norwegian Junior football

What does the study involve?
The participating teams are randomly allocated to either the intervention group or the control group. Teams in the intervention group conduct training based on a load progression model. The control group is asked to continue normal training activity.

What are the possible benefits and risks of participating?
The knowledge gained will be of use to researchers, doctors and coaching staff working with all team sports. This program have no side effects and there is no potential risk involved in participating in the study. The total duration of intervention and follow-up is 11 months. The percentage of players reporting a health issue is measured using a questionnaire via text message on the last Sunday of each month.

Where is the study run from?
Oslo Sports Trauma Research Center (Norway)

When is the study starting and how long is it expected to run for?
January 2018 to November 2018

Who is funding the study?
Oslo Sports Trauma Research Center (Norway)

Who is the main contact?
Torstein Dalen
torstein.dalen@nih.no

Contact information

Mr Torstein Dalen
Public

Sognsveien 220
Oslo
0863
Norway

Phone	+47 (0)93841844
Email	torstein.dalen@gmail.com

Mr Torstein Dalen
Scientific

Sognsveien 220
Oslo
0863
Norway

Phone	+47 (0)93841844
Email	torstein.dalen@nih.no

Study information

Primary study design	Interventional
Study design	Single-center cluster randomized controlled trial
Secondary study design	Cluster randomised trial
Study type	Participant information sheet
Scientific title	Training load management to reduce injuries in elite youth football: a cluster randomised controlled trial
Study objectives	Individual training load management can reduce risk of injuries among elite youth footballers.
Ethics approval(s)	The Norwegian School of Sciences Ethics Board, 21/12/2017, ref: 39-191217
Health condition(s) or problem(s) studied	Risk of injuries among elite youth footballers
Intervention	The trialists will cluster randomise on a team level. A computer-generated block randomisation will be performed, with block sizes of 4 and 6 in random order. After a team agrees to participate, the principal investigator will open a sealed envelope revealing their group assignment. The teams will be randomly allocated to either the intervention group (18 teams, 300 players) or the control group (18 teams, 300 players). Intervention group coaches will be given access to a digital tool for training load management. The coaches will plan their player's training weeks based on a progression model. The control group is asked to continue normal training activity. The total duration of intervention and follow-up is 11 months.
Intervention type	Other
Primary outcome measure(s)	Prevalence of health problems (percentage of players reporting a health issue), collected using the Oslo Sports Trauma Research Center Questionnaire via an SMS system on the last Sunday of each month
Key secondary outcome measure(s)	Incidence of injuries, collected through previously reported method (https://www.ncbi.nlm.nih.gov/pubmed/27034126) where the teams provide all time-loss injuries and illnesses
Completion date	30/11/2018

Eligibility

Participant type(s)	Healthy volunteer
Age group	Other
Sex	All
Target sample size at registration	600
Total final enrolment	482
Key inclusion criteria	1. Elite youth footballers competing in one of the three highest levels 2. Both genders 3. Aged 15-19
Key exclusion criteria	Unable to communicate in Scandinavian language
Date of first enrolment	15/01/2018
Date of final enrolment	25/01/2018

Locations

Countries of recruitment

Norway

Study participating centre

Norwegian School of Sports Sciences

0863
Norway

Results and Publications

Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Available on request
IPD sharing plan	The datasets generated during and analysed during the current study are available upon request from Torstein Dalen-Lorentsen (Torstein.dalen@nih.no). All data is non-identifiable.

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results	01/01/2021	13/10/2020	Yes	No
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes
Study website	Study website	11/11/2025	11/11/2025	No	Yes

Editorial Notes

13/10/2020: Publication reference, total final enrolment number and IPD sharing statement added.
13/11/2019: The intention to publish date has been changed from 31/12/2019 to 01/03/2020.