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Lower Extremity Joint Work During Acceleration, Deceleration, and Steady State Running

D.S. Blaise Williams III, Jonathan H. Cole, and Douglas W. Powell

Running during sports and for physical activity often requires changes in velocity through acceleration and deceleration. While it is clear that lower extremity biomechanics vary during these accelerations and decelerations, the work requirements of the individual joints are not well understood. The purpose of this investigation was to measure the sagittal plane mechanical work of the individual lower extremity joints during acceleration, deceleration, and steady-state running. Ten runners were compared during acceleration, deceleration, and steady-state running using three-dimensional kinematics and kinetics measures. Total positive and negative joint work, and relative joint contributions to total work were compared between conditions. Total positive work progressively increased from deceleration to acceleration. This was due to greater ankle joint work during acceleration. While there was no significant change in total negative work during deceleration, there was a greater relative contribution of the knee to total negative work with a subsequent lower relative ankle negative work. Each lower extremity joint exhibits distinct functional roles in acceleration compared with deceleration during level running. Deceleration is dominated by greater contributions of the knee to negative work while acceleration is associated with a greater ankle contribution to positive work.

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Locomotor Adaptations During RaceRunning in People With Neurological Motor Disorders

Mohsen Shafizadeh, Nicola Theis, and Keith Davids

, since the capacity of certain tissues to transmit and attenuate shock may be frequency dependent ( Smeathers, 1989 ). The frequency content and signal power of impact shock and tibia acceleration during stance phase of normal running are thought to be governed primarily by movement of the leg and center

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Effects of Preseason Training on the Sleep Characteristics of Professional Rugby League Players

Heidi R. Thornton, Jace A. Delaney, Grant M. Duthie, and Ben J. Dascombe

During the same training camp, 9 a research abstract showed that an increased acceleration/deceleration load (SumAccDec) was associated with very likely small increases in sleep duration (effect size [ES] = 0.27; ±0.16), time in bed (TIB; ES = 0.25; ±0.16), and sleep-onset latency (ES = 0.20; ±0

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Metabolic Power: A Step in the Right Direction for Team Sports

Ted Polglaze and Matthias W. Hoppe

demands of brief, nonsteady-state—and often high-intensity—accelerations cannot be directly measured. However, this is possible for steady-state incline running, where energy cost increases with slope but, as per running on level ground, is independent of speed at a given slope. 5 Accordingly

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Working Overtime: The Effects of Overtime Periods on Game Demands in Basketball Players

Aaron T. Scanlan, Robert Stanton, Charli Sargent, Cody O’Grady, Michele Lastella, and Jordan L. Fox

max ]) 4 demands while undertaking extensive physical requirements, including jumping (1.1 per min), accelerations (∼60), and change-of-direction movements (∼180) during game-play. 6 Despite the growing body of descriptive evidence quantifying game demands in basketball, the impact of overtime

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Match Acceleration and Deceleration Patterns in Female Collegiate Soccer Players

Jessica L. Trapp, Alicja B. Stannard, Julie K. Nolan, and Matthew F. Moran

positions ( Vescovi, 2012 ), the importance of rapid change of speed efforts (i.e., acceleration) and positional demands cannot be understated. With many deceleration efforts performed just prior to change of direction (COD) movements ( Bloomfield et al., 2007 ), the ability to train players appropriately

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Decision Making Influences Tibial Impact Accelerations During Lateral Cutting

Logan A. Lucas, Benjamin S. England, Travis W. Mason, Christopher R. Lanning, Taylor M. Miller, Alexander M. Morgan, and Thomas Gus Almonroeder

3 times an athlete’s body weight. 7 These impact forces generate a transient spike in acceleration which is transmitted throughout the musculoskeletal system from the foot to the head. 8 Although the lower-extremity musculature can help to attenuate these impact accelerations, passive tissues also

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Characterization of Head Acceleration Exposure During Youth Football Practice Drills

Ty D. Holcomb, Madison E. Marks, N. Stewart Pritchard, Logan Miller, Mark A. Espeland, Christopher M. Miles, Justin B. Moore, Kristie L. Foley, Joel D. Stitzel, and Jillian E. Urban

sport participation and long-term neurological effects. 1 – 12 Previous studies have also concluded that youth (ages 9–12 y) football athletes endure head acceleration events (HAEs) similar to the magnitude of those sustained by high school or college football athletes. 13 – 15 In recent years, youth

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Tibial Acceleration Reliability and Minimal Detectable Difference During Overground and Treadmill Running

Kevin G. Aubol, Jillian L. Hawkins, and Clare E. Milner

Tibial acceleration is thought to be related to overuse running injuries, particularly tibial stress fractures. 1 , 2 Peak axial tibial acceleration and peak resultant tibial acceleration are common outcome measures in studies of running. These measurements must be reliable so that the

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Age Does Not Attenuate Maximal Velocity Adaptations in the Ipsilateral and Contralateral Limbs During Unilateral Resistance Training

Garrett M. Hester, Zachary K. Pope, Mitchel A. Magrini, Ryan J. Colquhoun, Alejandra Barrera-Curiel, Carlos A. Estrada, Alex A. Olmos, and Jason M. DeFreitas

peak velocity (PV) and acceleration (sometimes termed rate of velocity development) of the knee extensors are negatively affected by age ( Thompson, Conchola, Palmer, & Stock, 2014 ; Wallace, Power, Rice, & Dalton, 2016 ). Similar to the effect of age on other rapid, time-sensitive measures (e