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Bassam A. Nabil, Mariam A. Ameer, Azza M. Abdelmohsen, Abeer F. Hanafy, Ahmed S. Yamani, Naglaa M. Elhafez and Salam M. Elhafez

measurement of normalized eccentric peak torque (NEPT). 14 Rare scientific studies in the literature explain the mechanical and anatomical adaptation of external shoulder joint musculature to any faulty mechanics at the elbow and wrist joints. 14 On the other hand, there are several compensatory strategies

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Paul Comfort, Thomas Dos’Santos, Paul A. Jones, John J. McMahon, Timothy J. Suchomel, Caleb Bazyler and Michael H. Stone

application of force during such activities. 2 , 3 For example, during high-velocity sprinting, foot contact times can be much less than 250 milliseconds, with a progressive decline in contact time as running velocity increases. 6 , 7 Interestingly, there is a strong association between isometric peak force

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Il-young Yu, Dong-kyu Lee, Myoung-Joo Kang and Jae-seop Oh

sample size (ver. 3.1.2; Franz Faul, University of Kiel, Kiel, Germany) in a pilot study of 5 subjects. A SD of isokinetic ER peak torque (PT) difference (5.4 Nm) was used. A priori calculation of the sample size was performed with a power of 0.80, alpha level of .05, and effect size of 0.97. The result

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Marisa Maia Leonardi-Figueiredo, Mariana Angélica de Souza, Elisangela Aparecida da Silva Lizzi, Luciano Fonseca Lemos de Oliveira, Julio Cesar Crescencio, Pedro Vellosa Schwartzmann, Lourenço Gallo Jr and Ana Claudia Mattiello-Sverzut

uptake or peak oxygen uptake (VO 2peak ), during the progressive cardiopulmonary exercise test ( 2 ). However, this test requires many resources in terms of qualified personnel and sophisticated instrumentation, which are not always available and limit the usefulness of this method in routine clinical

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Terry J. Housh, Glen O. Johnson, Dona J. Housh, Jeffrey R. Stout, Joseph P. Weir, Loree L. Weir and Joan M. Eckerson

The purpose of the present study was to examine age-related changes in isokinetic leg flexion and extension peak torque (PT), PT/body weight (PT/BW), and PT/fat-free weight (PT/FFW) in young wrestlers. Male wrestlers (N = 108; age M ± SD = 11.3 ± 1.5 years) volunteered to be measured for peak torque at 30, 180, and 300° · s−1. In addition, underwater weighing was performed to determine body composition characteristics. The sample was divided into six age groups (8.1−8.9, n = 10; 9.0−9.9, n= 11; 10.0−10.9, n = 25; 11.0−11.9, n = 22; 12.0−12.9, n = 28; 13.0−13.9, n = 12), and repeated measures ANOVAs with Tukey post hoc comparisons showed increases across age for PT, PT/BW, and PT/FFW. The results of this study indicated that there were age-related increases in peak torque that could not be accounted for by changes in BW or FFW. It is possible that either an increase in muscle mass per unit of FFW, neural maturation, or both, contributes to the increase in strength across age in young male athletes.

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Samantha J. Wilson, Bryan Christensen, Kara Gange, Christopher Todden, Harlene Hatterman-Valenti and Jay M. Albrecht

Acute static stretching has been shown to decrease muscle performance 1 ; however, chronic stretching has been shown to improve several athletic performance variables over time including 1-repetition maximum (1RM), 2 flexibility, gait economy, 3 running speed, 4 peak torque, 5 and vertical jump

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Kathleen U. Farmer

Peak performance is trainable through biofeedback, autogenic relaxation or quieting the mind, and visualization while in a theta brain wave state. How to achieve this integration of body, mind, and spirit is described in the following article. Research substantiates that mental practice in a receptive mind activates specific parts of the brain and ultimately enhances performance when the physical movements are acted out. Because most athletes are kinesthetic learners, their “visualizations” need to be complete experiences, encompassing sights, sounds, tastes, smells, and muscular sensations. This article presents techniques that clinicians can learn and pass on to athletes in their care.

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Daniel B. Hollander and Edmund O. Acevedo

The unique experience of swimming the English Channel is a test of mind and body to overcome multiple challenges. The purpose of this study was to examine psychological characteristics and reflective meanings of these swimmers. Eight English Channel swimmers were interviewed. Inductive and deductive analyses compared interviews and interpretations with the coinvestigator and swimmers. Themes included the cognitive orientations of mental toughness, while cognitive strategies included goal setting, Compartmentalization of time, and/or swimming distance, and self-regulation. Descriptions of the experience of the swim included an ease of swimming at the beginning, more aversive experiences in the middle, and a paradoxical euphoria and letdown upon completion of the swim. Several swimmers noted the perception of increased occupational effectiveness, self-confidence, and an awareness of unlimited potential. Whereas, other swimmers noted a more competitive post event focus. Reflective experiences supported Maslow’s notion that the meaning associated with a peak experience augments daily life.

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Mary Hellen Morcelli, Dain Patrick LaRoche, Luciano Fernandes Crozara, Nise Ribeiro Marques, Camilla Zamfolini Hallal, Mauro Gonçalves and Marcelo Tavella Navega

torque development thresholds predictive of functional gait speeds for each joint action. Until now, no study has simultaneously compared the strengths of the 3 primary lower limb joints and their relation with gait speed in older adults. Therefore, this study aims to test the ability of peak torque and

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Alex V. Rowlands, John M. Schuna Jr., Victoria H. Stiles and Catrine Tudor-Locke

Background:

Previous research has reported peak vertical acceleration and peak loading rate thresholds beneficial to bone mineral density (BMD). Such thresholds are difficult to translate into meaningful recommendations for physical activity. Cadence (steps/min) is a more readily interpretable measure of ambulatory activity.

Objective:

To examine relationships between cadence, peak vertical acceleration and peak loading rate during ambulation and identify the cadence associated with previously reported bone-beneficial thresholds for peak vertical acceleration (4.9 g) and peak loading rate (43 BW/s).

Methods:

Ten participants completed 8 trials each of: slow walking, brisk walking, slow running, and fast running. Acceleration data were captured using a GT3×+ accelerometer worn at the hip. Peak loading rate was collected via a force plate.

Results:

Strong relationships were identified between cadence and peak vertical acceleration (r = .96, P < .05) and peak loading rate (r = .98, P < .05). Regression analyses indicated cadences of 157 ± 12 steps/min (2.6 ± 0.2 steps/s) and 122 ± 10 steps/min (2.0 ± 0.2 steps/s) corresponded with the 4.9 g peak vertical acceleration and 43 BW/s peak loading rate thresholds, respectively.

Conclusions:

Cadences ≥ 2.0 to 2.6 steps/s equate to acceleration and loading rate thresholds related to bone health. Further research is needed to investigate whether the frequency of daily occurrences of this cadence is associated with BMD.