the upper part of the body, which remain passive during conventional walking (CW). 6 The NW requires a greater energy expenditure at a given speed compared to CW. 7 Thus, the increased energy expenditure does not correspond with an increase in perceived exertion. 8 Walking with poles, particularly
Anna Witkowska, Małgorzata Grabara, Dorota Kopeć, and Zbigniew Nowak
Talita Molinari, Tainara Steffens, Cristian Roncada, Rodrigo Rodrigues, and Caroline P. Dias
, 2003 ; Higbie et al., 1996 ; Lastayo et al., 2000 ; Norrbrand, Fluckey, Pozzo, & Tesch, 2008 ; Seger, Arvidsson, Thorstensson, & Seger, 1998 ) when compared with conventional strength training (CT; concentric and eccentric actions). In addition, larger increments in total strength were observed
Cindy Y. Lin, Liang-Ching Tsai, Joel Press, Yupeng Ren, Sun G. Chung, and Li-Qun Zhang
Gluteal-muscle strength has been identified as an important component of injury prevention and rehabilitation in several common knee injuries. However, many conventionally prescribed gluteal-strengthening exercises are not performed during dynamic weight-bearing activities, which is when most injuries occur.
To compare lower-limb muscle-activation patterns between conventional gluteal-strengthening exercises and off-axis elliptical exercises with motorized foot-plate perturbations designed to activate gluteal muscles during dynamic exercise.
Twelve healthy volunteers (26.1 ± 4.7 y) participated in the study. They performed 3 conventional exercises (single-leg squat, forward lunge, and clamshell) and 3 elliptical exercises (regular, while resisting an adduction force, and while resisting an internal-rotation torque). Gluteus medius (GMed) and maximus (GMax), quadriceps, hamstrings, and gastrocnemius muscle activations during each exercise were recorded using surface electromyography (EMG) and normalized to maximal voluntary isometric contraction (MVIC).
Normalized GMed EMG was the highest during the adduction-resistance elliptical exercise (22.4% ± 14.8% MVIC), significantly greater than forward lunge (8.2% ± 3.8% MVIC) and regular elliptical (6.4% ± 2.5% MVIC) and similar to clamshell (19.1% ± 8.8% MVIC) and single-leg squat (18.4% ± 7.9% MVIC). Normalized GMax EMG during adduction-resistance (11.1% ± 7.6% MVIC) and internal-rotation-resistance elliptical (7.4% ± 3.8% MVIC) was significantly greater than regular elliptical (4.4% ± 2.4% MVIC) and was similar to conventional exercises. The single-leg squat required more muscle activation from the quadriceps and gastrocnemius than the elliptical exercises.
Off-axis elliptical exercise while resisting an adduction force or internal-rotation torque activates gluteal muscles dynamically while avoiding excessive quadriceps activation during a functional weight-bearing activity compared with conventional gluteal-strengthening exercises.
Stephen P. Messier and Mary Ann Brody
This study examined the mechanics of translation and rotation during the conventional and handspring soccer throw-ins. Thirteen male collegiate soccer players were filmed at 100 fps while performing a conventional soccer throw-in for distance. Additionally, two male collegiate and two male youth league soccer players were filmed at 200 fps while performing a handspring throw-in. Analysis of the conventional throw-in revealed that rapid trunk flexion, and shoulder and elbow extension just prior to release appear to make important contributions to the performance variables (initial ball velocity, angle of release, range, angular momentum). Results of the handspring throw-in analysis suggest that the angular momentum generated during the preparatory and ball support phases was transferred to the arms, forearms, and ball during the latter stages of the movement. Although generalization to a larger population is limited, the results of this study suggest that the handspring throw-in technique has the potential to generate greater release velocities and longer throws, thereby enhancing scoring opportunities during throw-in situations.
Heiner Baur, Alessia Severina Groppa, Regula Limacher, and Lorenz Radlinger
Maximum strength and rate of force development (RFD) are 2 important strength characteristics for everyday tasks and athletic performance. Measurements of both parameters must be reliable. Expensive isokinetic devices with isometric modes are often used. The possibility of cost-effective measurements in a practical setting would facilitate quality control. The purpose of this study was to assess the reliability of measurements of maximum isometric strength (Fmax) and RFD on a conventional leg press. Sixteen subjects (23 ± 2 y, 1.68 ± 0.05 m, 59 ± 5 kg) were tested twice within 1 session. After warm-up, subjects performed 2 times 5 trials eliciting maximum voluntary isometric contractions on an instrumented leg press (1- and 2-legged randomized). Fmax (N) and RFD (N/s) were extracted from force-time curves. Reliability was determined for Fmax and RFD by calculating the intraclass correlation coefficient (ICC), the rest-retest variability (TRV), and the bias and limits of agreement. Reliability measures revealed good to excellent ICCs of .80-.93. TRV showed mean differences between measurement sessions of 0.4-6.9%. The systematic error was low compared with the absolute mean values (Fmax 5-6%, RFD 1-4%). The implementation of a force transducer into a conventional leg press provides a viable procedure to assess Fmax and RFD. Both performance parameters can be assessed with good to excellent reliability allowing quality control of interventions.
Fernando G. Beltrami and Timothy D. Noakes
the conventional incremental test, even when the verification phase was used. It remains unclear, however, whether the higher V ˙ O 2 max values found in these individual studies are a consistent physiological phenomenon that can be reproduced in different investigations. For instance, Taylor et
Lennart Scheys, Alberto Leardini, Pius D. Wong, Laurent Van Camp, Barbara Callewaert, Johan Bellemans, and Kaat Desloovere
The availability of detailed knee kinematic data during various activities can facilitate clinical studies of this joint. To describe in detail normal knee joint rotations in all three anatomical planes, 25 healthy subjects (aged 22–49 years) performed eleven motor tasks, including walking, step ascent and descent, each with and without sidestep or crossover turns, chair rise, mild and deep squats, and forward lunge. Kinematic data were obtained with a conventional lower-body gait analysis protocol over three trials per task. To assess the repeatability with standard indices, a representative subset of 10 subjects underwent three repetitions of the entire motion capture session. Extracted parameters with good repeatability included maximum and minimum axial rotation during turning, local extremes of the flexion curves during gait tasks, and stride times. These specific repeatable parameters can be used for task selection or power analysis when planning future clinical studies.
William J. Morgan
This essay addresses four main questions. The first is devoted to how I became interested in the philosophy of sport. The second question concerns how my academic career has evolved over time in line with various developments in the field that privileged certain lines of study over others and which largely marginalized philosophy in particular and the humanities in general. The third question centers on what I take to be my own main contributions to the philosophy of sport and what, if any, impact they may have had on the larger field of kinesiology. Finally, I offer my own brief prognosis of what I think the future has in store for the relationship between sport philosophy and kinesiology.
Maureen P. Fitzgerald, Mary Ann D. Sagaria, and Barbara Nelson
This study used a sociological career trajectory model to examine the career patterns of 200 male and female NCAA Division I, II, and III athletic directors. A normative career pattern derived from the literature on athletic directors was posited to compare the histories of incumbent NCAA athletic directors (ADs). The actual career experiences of ADs challenged the norm of the posited five-position sequence that begins with collegiate athlete; progresses through high school coach, collegiate coach, and associate or assistant director; and culminates with athletic director. Competing as a collegiate athlete and coaching at the college level were the two most frequent experiences underpinning the AD position. Differences from the posited norms were most likely to be associated with directors of NCAA Division II and III institutions and with women.
John F. Gaski
Over the past 3 decades or so, some variation and revision have been introduced into the recording, reporting, and interpretation of the prime historical benchmark of individual golf achievement: number of established major tournaments won. In the interest of accuracy, consistency, and even equity, some analytic record-keeping suggestions are proffered here, based on coherence and logic, toward presenting the history of golf’s major championships in the fairest possible way. Idiosyncrasies of that historical sequence mean that the resolution is not obvious and more taxonomic work remains to be done. However, acceptance of the principles and conventions proposed herein may move the golf history culture and even basic golf chronicling closer to advantageous closure. One competitive implication of this reanalysis applies, significantly, to the total of “majors” won by historical greats Jack Nicklaus, Bobby Jones, and Tiger Woods.