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Fédération Internationale de l’Automobile (FIA), Power, and Politics: A Socio-Historical Analysis

Hans Erik Næss

is to demonstrate not how much, but how little, the organization has changed, generally since its inauguration in 1904 and particularly since the radical changes in Formula 1 in the 1970s, with regards to stakeholder policy and power management. Therefore, drawing on archival sources as well as

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Trade-Off Between Maximal Power Output and Fatigue Resistance of the Knee Extensors for Older Men

Ryota Akagi, Yuta Nomura, Chiho Kawashima, Mari Ito, Kosuke Oba, Yuma Tsuchiya, Geoffrey A. Power, and Kosuke Hirata

Natural adult aging is associated with decreased neuromuscular fatigue resistance, evidenced by a decrease in neuromuscular power/strength, across a variety of physical activity levels ( Dalton et al., 2010 ; Sundberg, Kuplic, et al., 2018 ; Theou et al., 2008 ) and muscle groups ( Dalton et

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Measurement of Power in Selectorized Strength-Training Equipment

Andrea Biscarini

The author derived the exact analytical expression of the instantaneous joint power in exercises with single-joint, variable-resistance, selectorized strength-training equipment, taking into account all the relevant geometric, kinematic, and dynamic variables of both the movable equipment elements (resistance input lever, cam–pulley system, weight stack) and of the user’s exercising limb. A numerical algorithm was also designed to express, in the presence of a cam, the rectilinear kinematic variables of the weight stack as a function of the rotational kinematic variables of the resistance input lever, and vice versa. Given that information, one can measure the value of the instantaneous and mean joint power exclusively by means of a linear encoder placed on the weight stack or, alternatively, only by the use of an angular encoder placed on the rotational axis of the resistance lever. The results highlight that, for knee extension exercises with leg extension equipment, the real values of both instantaneous and mean joint power may differ by more than 50% in comparison with the values obtained by taking into account only the mass and velocity of the weight stack. These differences are notable not only in explosive exercises, but also whenever considerable joint velocities/accelerations occur within the range of motion.

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Adaptations in Bilateral Mechanical Power Patterns during Obstacle Avoidance Reveal Distinct Control Strategies for Limb Elevation versus Limb Progression

Assane E.S. Niang and Bradford J. McFadyen

The present study investigated the adaptations of specific power bursts during the combined contexts of the proximity (lead vs. trail limb) and height of an obstruction in relation to limb elevation versus progression. Ten young, adult, male subjects walked at their natural speed during unobstructed walking and the bilateral avoidance of moderate and high obstacles. Hip flexor generation power was unaffected by obstacle height for the leading limb and always delayed for the trailing limb. The knee extensor absorption power burst at toe-off was also eliminated for the trailing limb and was found to reappear in mid-swing. Few differences were seen for ankle push-off power. The results suggest that the hip joint is dedicated to limb advancement only, while the knee joint is directly involved in limb elevation and the control of multiarticular effects.

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ACTN3 R577X Polymorphism and Explosive Leg-Muscle Power in Elite Basketball Players

Nuria Garatachea, Zoraida Verde, Alejandro Santos-Lozano, Thomas Yvert, Gabriel Rodriguez-Romo, Francisco J. Sarasa, Sonsoles Hernández-Sánchez, Catalina Santiago, and Alejandro Lucia

Purpose:

To determine the association of the ACTN3 R577X polymorphism with leg-muscle explosive power in Spanish (white) elite basketball players and controls.

Participants:

100 (60 men) elite basketball players (cases) and 283 nonathletic controls.

Methods:

The authors assessed power performance by means of the vertical-squat and countermovement-jump tests.

Results:

Genotype distributions did not differ between groups (cases: 37.0% [RR], 42.0% [RX], and 21.0% [XX]; controls: 31.8% [RR], 49.8% [RX], and 18.4% [XX]; P = .353). The authors did not observe any effect of the ACTN3 R577X polymorphism on study phenotypes in either group, including when they performed the analyses separately in men and women. They found no association between the ACTN3 R577X polymorphism and the likelihood of being an elite basketball player using the dominant or the recessive model, and the results remained unaltered when the analyses were adjusted for sex, weight, height, and age or when performed for men and women separately.

Conclusions:

Although the ACTN3 R577X is associated with explosive muscle performance and this phenotype is important in the sport of basketball (ie, during jumps), the authors found no association with leg explosive power in elite basket players or with the status of being this type of athlete.

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A Case Study on Power and Politics in Organizations

Florian Hemme and Marlene A. Dixon

James Park has been hired as the new CEO by the board of directors of GoSports Inc., a large national sporting goods retailer, which has been battling economic and internal issues over the previous years. Despite Park’s experience at the helm of large companies in need of profound strategic and structural change, in his new position at GoSports he has been “butting heads” with a powerful collective of executives unhappy with the hire and threatened by the new CEO’s accolades. To complicate matters, rumor has it that the decision to hire Park was far from unanimous, with various factions vying for control in the company, waiting for a chance to fill the power vacuum a quick departure by Park would leave behind. After two weeks with the company, Park is called before the board of directors to report on the progress made and how he plans to return GoSports to its former glory.

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Sport Knowledge: The Effects of Division I Coach Communication on Student-Athlete Learning Indicators

Rikishi T. Rey, Gregory A. Cranmer, Blair Browning, and Jimmy Sanderson

techniques combined with effective uses of power may create environments conducive to optimal sporting experiences. Power is a promising framework from which to view coaches’ management of sporting environments and athletes’ learning ( Cranmer & Buckner, 2017 ; Martin et al., 2009 ; Turman, 2006 ), as

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Joint-Level Analyses of the Back Squat With and Without Intraset Rest

Jason D. Stone, Adam C. King, Shiho Goto, John D. Mata, Joseph Hannon, James C. Garrison, James Bothwell, Andrew R. Jagim, Margaret T. Jones, and Jonathan M. Oliver

), elicits a near linear decline in barbell velocity, and thus power output. 3 – 5 Recognizing that force and velocity are both required to maintain a given work capacity, muscular fatigue has been defined as the inability to maintain the required or expected power output. 6 Attenuated power production is

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Effects of Caffeine on Countermovement-Jump Performance Variables in Elite Male Volleyball Players

Hermann Zbinden-Foncea, Isabel Rada, Jesus Gomez, Marco Kokaly, Trent Stellingwerff, Louise Deldicque, and Luis Peñailillo

exertion, which suggests that caffeine ameliorates the discomfort produced by fatigue and enhances motor-unit recruitment. 13 When a high power output is required and during repeated-sprint events, the ergogenic effects are less consistent 12 ; several explanations may be put forward, such as variability

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The Effect of Sex, Maturity, and Training Status on Maximal Sprint Performance Kinetics

Adam Runacres, Kelly A. Mackintosh, and Melitta A. McNarry

and training status. The development of speed throughout adolescence is a nonlinear process with cross-sectional evidence in untrained boys from nonmotorized treadmills suggesting that sprint kinetics (ie, force and power) only significantly increase from prepubertal to pubertal maturity statuses