The aim of this study was to verify the concurrent validity and the biological error-free reliability of a novel low-cost commercial encoder (Ergonauta I). Validity protocol involved comparisons with a custom system and other encoder commercially available (Vitruve). Reliability protocols involved interdevices and interunit comparisons. No…

An a-posteriori multicentre reliability study was conducted to compare the reliability and magnitude of the maximum power (P[subscript max]) and optimal velocity (V[subscript opt]) between the force-power-velocity relationships during the leg cycle-ergometer and bench press throw exercises. The force-power-velocity relationships were determined in…

The purpose of this study was to overview recent bone loading measurements in physical activity, determine their validity and reliability, and recommend future research directions. A systematic search in three major databases was performed using combinations from a set of keywords, and the identified studies were selected using predetermined…

This study evaluated whether real-time applied load feedback and a predefined applied load limit improved inter-session reliability and measurement error of passive glenohumeral rotation range-of-motion measurements. Twenty-one male recreational overhead athletes completed two data collection sessions, approximately 1-week apart. Measurements of…

The aim of the study was to determine the convergent validity of a portable polysomnograph and an accelerometer for measuring sleep efficiency and movement in college students. Volunteers were 29 healthy students (males = 15, females = 14) who simultaneously wore the Nox T3 portable polysomnograph and the ActiGraph wGT3X-BT accelerometer. Both…

Males (n = 29) and females (n = 34) performed vertical jumps. Jump height was estimated from force platform data using five numerical methods and compared using intraclass correlation ([rho]), and linear and rank regression standard error of estimate ("SEE"). Take-off velocity plus center of mass height at take-off and mechanical work…

Where as video cameras are a reliable and established technology for the measurement of kinematic parameters, accelerometers are increasingly being employed for this type of measurement due to their ease of use, performance, and comparatively low cost. However, the majority of accelerometer-based studies involve a single channel due to the…

Many methods for the identification of key variables in movement patterns have the problem that direct transferability back to coaches or players is not easy; this is because the variables used are not presented in the language of most sport participants. Using a research strategy--from the coaches back to the coaches--proposed by Roth (1996),…

The reliability of a laser system was compared with the reliability of a video-based kinematic analysis in measuring displacement and velocity during running. Validity and reliability of the laser on static measures was also assessed at distances between 10 m and 70 m by evaluating the coefficient of variation and intraclass correlation…

In this pilot study of 16 children, we evaluated the reliability and validity of three accelerometers (Mini-Motionlogger [MML], Computer Science Applications, Inc. Actigraph [CSA], and BioTrainer) as indicators of energy expenditure and vertical ground reaction force. The children wore 2 of each type of monitor while they walked, ran, and…