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Effect of Forefoot and Midfoot Bending Stiffness on Agility Performance and Foot Biomechanics in Soccer

Daniel J. Brinkmann, Harald Koerger, Albert Gollhofer, and Dominic Gehring

adizero; adidas AG, Herzogenaurach, Germany). Although only the outsole construction differed systematically in forefoot and midfoot stiffness, the modification had no significant influence on the respective shoe weight. To increase the bending stiffness of the shoe complex, the material quantities

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The Revolution in Aging: Implications for Curriculum Development and Professional Preparation in Physical Education

C. Jessie Jones and Roberta E. Rikli

Despite dramatic increases in the older adult population, curriculum development in the area of physical activity and aging has been minimal or nonexistent in most physical education departments in higher education. As a consequence, many practitioners leading programs for older adults have had to rely primarily on self-study and on-the-job training for the knowledge and skills they need. The purpose of this paper is to suggest minimum competencies for preparing specialists in the field of physical activity and aging and to recommend corresponding curriculum development. Suggested core offerings for a concentration in physical activity and aging are presented, including specific course content for three specialty courses: physical activity and aging, physical assessment and exercise programming for older adults, and therapeutic exercise for age related chronic conditions. In view of the fact that many departments are faced with declining budgets and program cutbacks, alternative strategies for curricular revision and for integrating gerontological content into the existing physical education curriculum are discussed.

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Influence of a Full-Body Compression Suit on Trunk Positioning and Knee Joint Mechanics During Lateral Movements

Guillaume Mornieux, Elmar Weltin, Monika Pauls, Franz Rott, and Albert Gollhofer

was triggered by breaking a light beam (M18 series, Panasonic Electric Works Europe AG, Holzkirchen, Germany), 0.04 m above the plate, to compensate for the delay in activation of the motor-driven plate. Secondly, participants were asked to perform either cutting maneuvers to 45°, crossovers to −20

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Concurrent Validity of the Garmin Vivofit®4 to Accurately Record Step Count in Older Adults in Challenging Environments

Jacinta I. Foster, Katrina L. Williams, Barbra H.B. Timmer, and Sandra G. Brauer

by Sonova AG as part of a larger study series. The grant sponsors were not involved in study design, collection, analysis, or interpretation of data, writing of the manuscript, or the decision to submit the manuscript for publication. All authors declare that they have no professional relationship

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Evaluation of a Kinematically-Driven Finite Element Footstrike Model

Iain Hannah, Andy Harland, Dan Price, Heiko Schlarb, and Tim Lucas

A dynamic finite element model of a shod running footstrike was developed and driven with 6 degree of freedom foot segment kinematics determined from a motion capture running trial. Quadratic tetrahedral elements were used to mesh the footwear components with material models determined from appropriate mechanical tests. Model outputs were compared with experimental high-speed video (HSV) footage, vertical ground reaction force (GRF), and center of pressure (COP) excursion to determine whether such an approach is appropriate for the development of athletic footwear. Although unquantified, good visual agreement to the HSV footage was observed but significant discrepancies were found between the model and experimental GRF and COP readings (9% and 61% of model readings outside of the mean experimental reading ± 2 standard deviations, respectively). Model output was also found to be highly sensitive to input kinematics with a 120% increase in maximum GRF observed when translating the force platform 2 mm vertically. While representing an alternative approach to existing dynamic finite element footstrike models, loading highly representative of an experimental trial was not found to be achievable when employing exclusively kinematic boundary conditions. This significantly limits the usefulness of employing such an approach in the footwear development process.

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Validation of the Digiwalker™ Pedometer for Measuring Physical Activity in Young Children

David P. McKee, Colin A.G. Boreham, Marie H. Murphy, and Alan M. Nevill

Activity measurement using a uniaxial pedometer was validated against behavioral observation using the Children’s Activity Rating Scale (CARS) in 30 three- to four-year-old children in a nursery school setting. Correlations were calculated for individual children, whereas the relationship for the total group was investigated using multilevel linear regression. The mean counts for boys and girls for the Digiwalker™ were 66.8 (± 64.0) and 47.4 (± 61.3; p < .01) steps per 3 minutes, respectively, whereas the mean CARS scores for boys and girls were 1.8 (± 0.6) and 1.6 (± 0.6; p < .01), respectively. Within-child correlations for CARS versus Digiwalker counts ranged from 0.64 to 0.95 with a median value of 0.86, whereas the multilevel analysis provided strong evidence of a relationship between CARS and Digiwalker (all p < .001). Data from the current study show that gender differences in physical levels exist in very young children and support the utility of the Digiwalker pedometer for assessing physical activity in this age group.

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Agreement of Sedentary Behavior Metrics Derived From Hip- and Thigh-Worn Accelerometers Among Older Adults: With Implications for Studying Physical and Cognitive Health

John Bellettiere, Fatima Tuz-Zahra, Jordan A. Carlson, Nicola D. Ridgers, Sandy Liles, Mikael Anne Greenwood-Hickman, Rod L. Walker, Andrea Z. LaCroix, Marta M. Jankowska, Dori E. Rosenberg, and Loki Natarajan

, sedentary behavior has been defined as all waking behaviors while in a seated or lying posture that result in an energy expenditure ≤1.5 metabolic equivalents ( Tremblay et al., 2017 ). When measured using ActiGraph (AG) accelerometers worn around the participant’s hip, sedentary time is estimated based on

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Use of Objective Measures to Estimate Sedentary Time in Youth

Scott E. Crouter, Paul R. Hibbing, and Samuel R. LaMunion

pertains to assessments of SB in youth. The widespread adoption of objective measures of SB has occurred rapidly, and posture measurement has been advanced through the use of accelerometer-based devices, such as the ActiGraph GT3X+ (AG) and activPAL (AP). However, information about the validity of these

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Dominant vs. Non-Dominant Wrist Placement of Activity Monitors: Impact on Steps per Day

Susan Park, Lindsay P. Toth, Paul R. Hibbing, Cary M. Springer, Andrew S. Kaplan, Mckenzie D. Feyerabend, Scott E. Crouter, and David R. Bassett

monitor that includes a triaxial accelerometer. For this study, GT9X monitors were initialized at 80 Hz using the ActiLife 6 software (version 6.13.1). After data collection, the raw data were downloaded and processed with and without the low frequency extension (AG-LFE and AG-noLFE, respectively), and

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The Intrinsic Properties of ActiGraph Counts and Alternatives

Jan Christian Brønd, Niels Christian Møller, and Anders Grøntved

Physical activity (PA) is defined as any bodily movement produced by skeletal muscles that require an increased energy expenditure (EE; Caspersen et al., 1985 ) and this is also the foundation for studying PA in regard to health. Over the past three decades, the ActiGraph (AG) counts PA summary