Seyed Hamed Mousavi1, Juha M Hijmans2, Forough Moeini3, Reza Rajabi3, Reed Ferber4, Henk van der Worp5, Johannes Zwerver6. 1. University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands; University of Tehran, Faculty of Physical Education and Sport Sciences, Department of Health and Sport Medicine, Tehran, Iran. Electronic address: s.h.mousavi@umcg.nl. 2. University of Groningen, University Medical Center Groningen, Department of Rehabilitation Medicine, Groningen, the Netherlands. 3. University of Tehran, Faculty of Physical Education and Sport Sciences, Department of Health and Sport Medicine, Tehran, Iran. 4. University of Calgary, Faculty of Kinesiology, Calgary, Canada; Running Injury Clinic, Calgary, Canada; University of Calgary, Faculty of Nursing, Calgary, Canada. 5. University of Groningen, University Medical Center Groningen, Center for Human Movement Science, the Netherlands. 6. University of Groningen, University Medical Center Groningen, Center for Human Movement Science, the Netherlands; Department of Sports Medicine, Gelderse Vallei Hospital, Ede, the Netherlands.
Abstract
OBJECTIVE: To investigate the validity and reliability of a smartphone application for selected lower-limb kinematics during treadmill running. DESIGN: Validity and reliability study. SETTING: Biomechanics laboratory. PARTICIPANTS: Twenty healthy female runners. MAIN OUTCOME MEASURE(S): Sagittal-plane hip, knee, and ankle angle and rearfoot eversion were assessed using the Coach's Eye Smartphone application and a 3D motion capture system. Paired t-test and intraclass correlation coefficients (ICC) established criterion validity of Coach's Eye; ICC determined test-retest and intrarater/interrater reliability. Standard error of measurement (SEM) and minimal detectable change (MDC) were also reported. RESULTS: Significant differences were found between Coach's Eye and 3D measurements for ankle angle at touchdown and knee angle at toe-off (p < 0.05). ICCs for validity of Coach's Eye were excellent for rearfoot eversion at touchdown (ICC = 0.79) and fair-to-good for the other kinematics (range 0.51-0.74), except for hip at touchdown, which was poor (ICC = 0.36). Test-retest (range 0.80-0.92), intrarater (range 0.95-0.99) and interrater (range 0.87-0.94) ICC results were excellent for all selected kinematics. CONCLUSION: Coach's Eye can be used as a surrogate for 3D measures of knee and rearfoot in/eversion at touchdown, and hip, ankle, and rearfoot in/eversion at toe-off, but not for hip and ankle at touchdown or knee at toe-off. Reliable running kinematics were obtained using Coach's Eye, making it suitable for repeated measures.
OBJECTIVE: To investigate the validity and reliability of a smartphone application for selected lower-limb kinematics during treadmill running. DESIGN: Validity and reliability study. SETTING: Biomechanics laboratory. PARTICIPANTS: Twenty healthy female runners. MAIN OUTCOME MEASURE(S): Sagittal-plane hip, knee, and ankle angle and rearfoot eversion were assessed using the Coach's Eye Smartphone application and a 3D motion capture system. Paired t-test and intraclass correlation coefficients (ICC) established criterion validity of Coach's Eye; ICC determined test-retest and intrarater/interrater reliability. Standard error of measurement (SEM) and minimal detectable change (MDC) were also reported. RESULTS: Significant differences were found between Coach's Eye and 3D measurements for ankle angle at touchdown and knee angle at toe-off (p < 0.05). ICCs for validity of Coach's Eye were excellent for rearfoot eversion at touchdown (ICC = 0.79) and fair-to-good for the other kinematics (range 0.51-0.74), except for hip at touchdown, which was poor (ICC = 0.36). Test-retest (range 0.80-0.92), intrarater (range 0.95-0.99) and interrater (range 0.87-0.94) ICC results were excellent for all selected kinematics. CONCLUSION: Coach's Eye can be used as a surrogate for 3D measures of knee and rearfoot in/eversion at touchdown, and hip, ankle, and rearfoot in/eversion at toe-off, but not for hip and ankle at touchdown or knee at toe-off. Reliable running kinematics were obtained using Coach's Eye, making it suitable for repeated measures.
Authors: Seyed Hamed Mousavi; Laurens van Kouwenhove; Reza Rajabi; Johannes Zwerver; Juha M Hijmans Journal: PLoS One Date: 2021-02-10 Impact factor: 3.240
Authors: Shirley S M Fong; Louisa M Y Chung; Yang Gao; Jeff Chak Wai Lee; Tak Ching Chang; Ada W W Ma Journal: Medicine (Baltimore) Date: 2022-02-18 Impact factor: 1.817