Correction

This article refers to:

Effectiveness of wearable technology to optimize youth soccer players’ off-training behaviour and training responses: a parallel group randomized trial

Article title: Effectiveness of wearable technology to optimize youth soccer players’ off-training behaviour and training responses: a parallel group randomized trial.

Journal: Science and Medicine in Football

Author names and affiliations

Nuno Mateus ^a,b,*, Juliana Exel ^c, Sara Santos ^a,b, Bruno Gonçalves ^d,e,f, and Jaime Sampaio ^a,b

^a Research Center in Sports Sciences, Health Sciences and Human Development, CIDESD, CreativeLab Research Community, Vila Real, Portugal

^b University of Tras-os-Montes and Alto Douro School of Life Sciences and Environment, Department of Sports Science, Exercise and Health, University of Trás-os-Montes e Alto Douro, Vila Real, Portugal

^c Department of Sport Science Biomechanics, Kinesiology and Computer Science, University of Vienna, 1150 Vienna, Austria

^d Departamento de Desporto e Saúde, Escola de Ciências e Tecnologia, Universidade de Évora, 7005-150 Évora, Portugal

^e Comprehensive Health Research Centre (CHRC), 7005-150 Évora, Portugal

^f Portugal Football School, Portuguese Football Federation, 1250-012 Oeiras, Portugal

DOI: https://doi.org/10.1080/24733938.2022.2114604

The previously published manuscript had two errors that we need to report and correct: the research design was misclassified and there was no information describing that randomization was stratified by the team. Therefore, we carried out the changes and reanalysed the data, adjusting for the stratifying variable, according to Kernan et al. (1999) and Kahan and Morris (2013) procedures, as suggested by the authors of the letter and the journal Editors. None of the emends impacted the discussion and conclusions. Therefore, the manuscript should be read as follows:

Title: Effectiveness of wearable technology to optimize youth soccer players’ off-training behaviour and training responses: a parallel group randomized trial

Abstract

Purpose: A parallel group randomized trial examined the effect of activity wristbands on young players’ off-training PA and SB profiles; assessed the added value of wearable wristbands with PA warnings; and investigated whether manipulating off-training PA can affect the players’ training responses.

Statistical Analysis: An analysis of covariance (ANCOVA) quantified the effect of Fitbit wristband configurations (with a reminder to move or without a reminder to move) on the off-training PA and soccer training external load variables. The independent variable group had two levels (REM and nREM). The off-training PA and training load values collected in the first week were introduced in the model as a covariate, the groups were designated fixed factors and the off-training PA and training load from the third week were the dependent variables. The team was also included as a covariate and the between-group differences post-intervention were adjusted for baseline and team.

Table 1. Between-group differences of the off-training PA and soccer training external load variables.

	Group differences (baseline as covariate)				Group differences (baseline and team as covariates)
Variables	Estimate	95% CI for mean difference (lower; upper)	p		Estimate	95% CI for mean difference (lower; upper)	p
Off-training PA
Sedentary PA (min)	-0.36	-2.54; 1.83	0.74		-0.35	-2.57; 1.87	0.75
Light PA (min)	0.16	-1.22; 1.54	0.82		0.17	-1.23; 1.57	0.81
Moderate PA (min)	-0.24	-0.71; 0.23	0.31		-0.21	-0.67; 0.24	0.35
Vigorous PA (min)	0.24	-0.94; 1.42	0.68		0.22	-0.96; 1.39	0.71
MVPA (min)	0.02	-1.36; 1.40	0.98		0.01	-1.39; 1.41	0.99
SB bouts (a.u)	-0.01	-0.11; 0.09	0.86		-0.01	-0.12; 0.09	0.87
Daily steps (a.u)	8.41	-66.88; 83.69	0.82		7.84	-68.02; 83.70	0.83
Training external load
Distance covered (m)	1.04	-3.44; 5.52	0.64		1.14	-3.39; 5.66	0.61
Running (m)	0.32	-2.68; 3.31	0.83		0.42	-2.60; 3.43	0.78
High-intensity running (m)	0.04	-1.38; 1.46	0.95		0.05	-1.39; 1.49	0.95
Sprinting (m)	0.12	-0.59; 0.85	0.73		0.12	-0.60; 0.85	0.73
Accelerations (a.u)	-0.05	-3.12; 3.02	0.97		0.50	-0.72; 1.73	0.41
Decelerations (a.u)	-0.14	-2.53; 2.25	0.91		0.26	-0.77; 1.29	0.61
Impacts (a.u)	0.01	-0.09; 0.12	0.87		0.01	-0.09; 0.12	0.85
Player Load (a.u)	0.00	-0.02; 0.02	0.96		0.00	-0.02; 0.02	0.96

Acknowledgements

The authors wish to thank the call of attention received by the Science and Medicine in Football Editors and the authors from the letter, which helped us publish this erratum and improve the manuscript.