agility as an open motor skill characterized by unpredictable events rather than preplanned movements often seen in activities such as straight sprints or running to and fro in a zigzag manner ( 21 ). In addition, their model recognizes the important contribution of several personal physical
Search Results
Reliability and Validity of the Ladder Agility Test Among Children
Bouwien Smits-Engelsman, Wendy Aertssen, and Emmanuel Bonney
Continuous Jumps Enhance Twitch Peak Torque and Sprint Performance in Highly Trained Sprint Athletes
Haiko B. Zimmermann, Débora Knihs, Fernando Diefenthaeler, Brian MacIntosh, and Juliano Dal Pupo
results on the performance of drop jumps, 13 vertical jumps, 14 , 15 long jump, 16 supramaximal cycling time-trial, 17 and 1000-m running performance time. 18 However, few studies have tested the effect of these CAs on sprint performance. Till and Cooke 19 found that a single set of 5 vertical jumps
Task and Skill Level Constraints on the Generality of the Proximal–Distal Principle for Within-Limb Movement Coordination
Karl M. Newell and Gareth Irwin
drop landing, but with the need to dissipate the reactive forces of foot contact with the surface of support in a cyclical sequence over time. A representative example of the directional reversal of proximal–distal control is shown in an analysis of the early steps of sprinters leaving the blocks ( von
Analysis of Sprint Ski Mountaineering Performance
Alessandro Fornasiero, Simone Fornoni, Alexa Callovini, Beatrice Todesco, Aldo Savoldelli, Federico Schena, Hans-Christer Holmberg, Barbara Pellegrini, and Lorenzo Bortolan
downhill, and calls for the ability to descend effectively steep off-piste slopes. 2 , 3 The current 5 major formats for ski mountaineering competitions, that is, the Sprint, Vertical, and Individual disciplines, in which the athletes compete individually, and the Team, and Relay, involving teams of 2 or
Individual Step Characteristics During Sprinting in Unilateral Transtibial Amputees
Hiroaki Hobara, Sakiko Saito, Satoru Hashizume, Hiroyuki Sakata, and Yoshiyuki Kobayashi
The average velocity of a 100-m sprint is the product of the average step frequency and average step length. Although both parameters are inversely correlated, an increase in 1 factor will result in an improvement in sprint velocity, provided the other factor does not undergo a proportionately
Differences in Strength, Speed, and Power Performance Between Visually Impaired Paralympic and Olympic Sprinters
Tomás T. Freitas, Pedro E. Alcaraz, Ciro Winckler, Santiago Zabaloy, Lucas A. Pereira, and Irineu Loturco
Sprint races (ie, 100 and 200 m) are among the most exciting events in both the Olympic and Paralympic Games. Every 4 years, the fastest men and women in the world compete for a chance to write their names in the history books as Olympic heroes. According to the official data by World Athletics
Electromyography Normalization Methods for High-Velocity Muscle Actions: Review and Recommendations
Nick Ball and Joanna Scurr
Electromyograms used to assess neuromuscular demand during high-velocity tasks require normalization to aid interpretation. This paper posits that, to date, methodological approaches to normalization have been ineffective and have limited the application of electromyography (EMG). There is minimal investigation seeking alternative normalization methods, which must be corrected to improve EMG application in sports. It is recognized that differing normalization methods will prevent cross-study comparisons. Users of EMG should aim to identify normalization methods that provide good reliability and a representative measure of muscle activation. The shortcomings of current normalization methods in high-velocity muscle actions assessment are evident. Advances in assessing alternate normalization methods have been done in cycling and sprinting. It is advised that when normalizing high-intensity muscle actions, isometric methods are used with caution and a dynamic alternative, where the muscle action is similar to that of the task is preferred. It is recognized that optimal normalization methods may be muscle and task dependent.
SPRINTING. . . Dietary Approaches to Optimize Training Adaptation and Performance
Gary J. Slater, Jennifer Sygo, and Majke Jorgensen
Sprint performance, or the ability to generate maximal velocities, is important to competitive success across a range of sports including athletics events and team sports. The latter are characterized by repeated high-intensity sprints. By contrast, the track sprinter is concerned only with
Effects of Altitude on Performance of Elite Track-and-Field Athletes
Michael J. Hamlin, Will G. Hopkins, and Stephen C. Hollings
Purpose:
Lower barometric air pressure at altitude can affect competitive performance of athletes in some sports. Reported here are the effects of various altitudes on elite track-and-field athletes’ performance.
Methods:
Lifetime track-and-field performances of athletes placed in the top 16 in at least 1 major international competition between 2000 and 2009 were downloaded from the database at tilastopaja.org. There were 132,104 performances of 1889 athletes at 794 venues. Performances were logtransformed and analyzed using a mixed linear model with fixed effects for 6 levels of altitude and random quadratic effects to adjust for athlete age.
Results:
Men’s and women’s sprint events (100–400 m) showed marginal improvements of ~0.2% at altitudes of 500–999 m, and above 1500 m all but the 100- and 110-m hurdles showed substantial improvements of 0.3–0.7%. Some middle- and long-distance events (800–10,000 m) showed marginal impairments at altitudes above 150 m, but above 1000 m the impairments increased dramatically to ~2–4% for events >800 m. There was no consistent trend in the effects of altitude on field events up to 1000 m; above 1000 m, hammer throw showed a marginal improvement of ~1% and discus was impaired by 1–2%. Above 1500 m, triple jump and long jump showed marginal improvements of ~1%.
Conclusions:
In middle- and long-distance runners, altitudes as low as 150 to 299 m can impair performance. Higher altitudes (≥1000 m) are generally required before decreases in discus performance or enhancements in sprinting, triple and long jump, or hammer throw are seen.
Impact of Sled Loads on Performance and Kinematics of Elite Sprinters and Rugby Players
Fernando Pareja-Blanco, Lucas A. Pereira, Valter P. Reis, Victor Fernandes, Ademir F.S. Arruda, Aristide Guerriero, Pedro E. Alcaraz, Tomás T. Freitas, and Irineu Loturco
Resisted sprint methods allow athletes to reproduce the unresisted sprinting technique with the advantage of providing specific mechanical overload. 1 One of the most popular resisted sprint methods is resisted sled training (RST), which involves maximum sprint efforts while towing a sled device
