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Optimizing the Team for Required Power During Track-Cycling Team Pursuit

Levi Heimans, Wouter R. Dijkshoorn, Marco J.M. Hoozemans, and Jos J. de Koning

(Ap) and a drag coefficient (Cd), which is related to the shape of an object and the efficiency with which it moves through air. 6 The product of Ap and Cd is known as drag area (Ad). Reduction of this aerodynamic drag as a result of drafting can be expressed as a ratio (percentage) of the required

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Biomechanics of Elite Performers: Economy and Efficiency of Movement

Geoffrey T. Burns, Kenneth M. Kozloff, and Ronald F. Zernicke

movement. Why? Beyond its role in our evolutionary history, it is not unreasonable to wonder—why should we still focus on efficient movement? It is easy to appreciate the role of efficiency in optimizing athletic performance, where competition puts a premium on maximizing effectiveness while minimizing

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The Influence of Anxiety on Visual Attention in Climbing

Arne Nieuwenhuys, J. Rob Pijpers, Raôul R.D. Oudejans, and Frank C. Bakker

The object of the current study was to investigate anxiety-induced changes in movement and gaze behavior in novices on a climbing wall. Identical traverses were situated at high and low levels on a climbing wall to manipulate anxiety. In line with earlier studies, climbing times and movement times increased under anxiety. These changes were accompanied by similar changes in total and average fixation duration and the number of fixations, which were primarily aimed at the holds used for climbing. In combination with these findings, a decrease in search rate provided evidence for a decrease in processing efficiency as anxiety increased.

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Recovery of Cycling Gross Efficiency After Time-Trial Exercise

Sjors Groot, Lars H.J. van de Westelaken, Dionne A. Noordhof, Koen Levels, and Jos J. de Koning

According to the performance model of Joyner and Coyle, 1 performance power output or velocity is mainly determined by (1) maximal oxygen uptake ( V ˙ O 2 max), (2)  V ˙ O 2 at the lactate threshold, (3) performance O 2 deficit (ie, anaerobic capacity), and (4) efficiency. The efficiency of an

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The Cycling Physiology of Miguel Indurain 14 Years After Retirement

Iñigo Mujika

Age-related fitness declines in athletes can be due to both aging and detraining. Very little is known about the physiological and performance decline of professional cyclists after retirement from competition. To gain some insight into the aging and detraining process of elite cyclists, 5-time Tour de France winner and Olympic Champion Miguel Indurain performed a progressive cycle-ergometer test to exhaustion 14 y after retirement from professional cycling (age 46 y, body mass 92.2 kg). His maximal values were oxygen uptake 5.29 L/min (57.4 mL · kg−1 · min−1), aerobic power output 450 W (4.88 W/kg), heart rate 191 beats/min, blood lactate 11.2 mM. Values at the individual lactate threshold (ILT): 4.28 L/min (46.4 mL · kg−1 · min−1), 329 W (3.57 W/kg), 159 beats/min, 2.4 mM. Values at the 4-mM onset of blood lactate accumulation (OBLA): 4.68 L/min (50.8 mL · kg−1 · min−1), 369 W (4.00 W/kg), 170 beats/min. Average cycling gross efficiency between 100 and 350 W was 20.1%, with a peak value of 22.3% at 350 W. Delta efficiency was 27.04%. Absolute maximal oxygen uptake and aerobic power output declined by 12.4% and 15.2% per decade, whereas power output at ILT and OBLA declined by 19.8% and 19.2%. Larger declines in maximal and submaximal values relative to body mass (19.4–26.1%) indicate that body composition changed more than aerobic characteristics. Nevertheless, Indurain’s absolute maximal and submaximal oxygen uptake and power output still compare favorably with those exhibited by active professional cyclists.

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Opposition Skill Efficiency During Professional Rugby Union Official Games Is Related to Horizontal Force-Production Capacities in Sprinting

Paul Glaise, Isabelle Rogowski, Pierre Samozino, Jean-Benoit Morin, Baptiste Morel, and Cyril Martin

Rooyen et al 14 have demonstrated that a forward leaning and obliquely angled position of the player’s torso before contact was related to the tackle efficiency in international rugby union while executing front-on tackles reduced offloads and tackle breaks for the ball carrier. 15 In both situations

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Effect of Shoes on Stiffness and Energy Efficiency of Ankle-Foot Orthosis: Bench Testing Analysis

Toshiki Kobayashi, Fan Gao, Nicholas LeCursi, K. Bo Foreman, and Michael S. Orendurff

orthoses. The mechanical properties of AFOs, such as stiffness (moment per degree) and energy efficiency (ratio of released energy to stored energy), have been characterized using various mechanical testing devices, 1 – 3 and their effects on gait in individuals with neuromuscular diseases have been

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Longitudinal Relationships Between Maturation, Technical Efficiency, and Performance in Age-Group Swimmers: Improving Swimmer Evaluation

Shaun Abbott, Goshi Yamauchi, Mark Halaki, Marcela Torres Castiglioni, James Salter, and Stephen Cobley

positions coupled with complementary (biomechanically appropriate) arm and leg actions. 20 While challenging to quantify, reliable indicators of estimating technical skill proficiency, such as stroke index (SI) and arm propelling efficiency, have been developed . 21 Field-based assessment of these

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Effect of Aquatic Exercise on Sleep Efficiency of Adults With Chronic Musculoskeletal Pain

Billy C.L. So, Sze C. Kwok, and Paul H. Lee

beneficial effects of aquatic PA on objectively measured sleep quality in individuals with chronic MSK pain. This study was designed to investigate the effect of moderate-intensity (aerobic) aquatic exercise on sleep efficiency, sleep quality, pain, stress, and PA using an ActiGraph (Pensacola, FL) and self

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Marathon Pace Control in Masters Athletes

Derek Breen, Michelle Norris, Robin Healy, and Ross Anderson

fluctuations in running speed. This is an important consideration for all masters athletes, independent of age and gender. To highlight the potential benefits of adopting a more controlled pace, pacing profiles were calculated to examine potential improvements in 40-km-marathon time and efficiency. These