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. 2019 Aug 9:7:e7485.
doi: 10.7717/peerj.7485. eCollection 2019.

Test-retest reliability of a smartphone app for measuring core stability for two dynamic exercises

Paloma Guillén-Rogel  1 , Cristina Franco-Escudero  1 , Pedro J Marín  2
Affiliations

Test-retest reliability of a smartphone app for measuring core stability for two dynamic exercises

Paloma Guillén-Rogel et al. PeerJ. .

Abstract

Background: Recently, there has been growing interest in using smartphone applications to assess gait speed and quantify isometric core stability exercise intensity. The purpose of this study was to investigate the between-session reliability and minimal detectable change of a smartphone app for two dynamic exercise tests of the lumbopelvic complex.

Methods: Thirty-three healthy young and active students (age: 22.3 ± 5.9 years, body weight: 66.9 ± 11.3 kg, height: 167.8 ± 10.3 cm) participated in this study. Intraclass correlation coefficient (ICC), coefficient of variation (%CV), and Bland-Altman plots were used to verify the reliability of the test. The standard error of measurement (SEM) and the minimum detectable difference (MDD) were calculated for clinical applicability.

Results: The ICCs ranged from 0.73 to 0.96, with low variation (0.9% to 4.8%) between days of assessments. The Bland-Altman plots and one-sample t-tests (p > 0.05) indicated that no dynamic exercise tests changed systematically. Our analyses showed that SEM 0.6 to 1.5 mm/s-2) and MDD (2.1 to 3.5 mm/s-2).

Conclusion: The OCTOcore app is a reliable tool to assess core stability for two dynamic exercises. A minimal change of 3.5 mm/s-2 is needed to be confident that the change is not a measurement error between two sessions.

Keywords: Accelerometer; Assessment; Lumbopelvic-hip complex; Mobile technology; Screening.

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Conflict of interest statement

Pedro J. Marín is the designer of the app mentioned.

Figures

Figure 1
Figure 1. Partial range single leg deadlift test with the left heel (A) and the right heel (B) touching the wall.
Figure 2
Figure 2. Variation of bird-dog exercise test raising the left (A) and (B) right arm to the side following the direction of the OctoBalance® line.
Figure 3
Figure 3. Bland–Altman plots representing mean differences and 95% limits of agreement between Day 1 and Day 2.
(A) partial range single leg deadlift (SLD) right leg, (B) partial range single leg deadlift (SLD) left leg, (C) variation of bird-dog (BD) right leg, (D) variation of bird-dog (BD) left leg, (E) partial range single leg deadlift (SLD) composite (right and left), and (F) variation of bird-dog (BD) composite (right and left).
See this image and copyright information in PMC

References

    1. Adusumilli G, Joseph SE, Samaan MA, Schultz B, Popovic T, Souza RB, Majumdar S. iPhone sensors in tracking outcome variables of the 30-second chair stand test and stair climb test to evaluate disability: cross-sectional pilot study. JMIR Mhealth Uhealth. 2017;5:e166. doi: 10.2196/mhealth.8656. - DOI - PMC - PubMed
    1. Atkinson G, Nevill AM. Statistical methods for assessing measurement error (reliability) in variables relevant to sports medicine. Sports Medicine. 1998;26:217–238. doi: 10.2165/00007256-199826040-00002. - DOI - PubMed
    1. Barbado D, Barbado LC, Elvira JLL, Dieen JHV, Vera-Garcia FJ. Sports-related testing protocols are required to reveal trunk stability adaptations in high-level athletes. Gait Posture. 2016;49:90–96. doi: 10.1016/j.gaitpost.2016.06.027. - DOI - PubMed
    1. Barbado D, Irles-Vidal B, Prat-Luri A, Garcia-Vaquero MP, Vera-Garcia FJ. Training intensity quantification of core stability exercises based on a smartphone accelerometer. PLOS ONE. 2018;13:e0208262. doi: 10.1371/journal.pone.0208262. - DOI - PMC - PubMed
    1. Bilney B, Morris M, Webster K. Concurrent related validity of the GAITRite walkway system for quantification of the spatial and temporal parameters of gait. Gait Posture. 2003;17:68–74. doi: 10.1016/S0966-6362(02)00053-X. - DOI - PubMed

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