, is it better to select 1 peak from the average profile or take an average of peaks selected from each trial? Unfortunately, how peak values from multiple trials are chosen is inconsistent and/or unclear in the literature. For example, some researchers identified individual trial peaks from a
Kevin D. Dames, Jeremy D. Smith and Gary D. Heise
Tzu-Chieh Liao, Joyce H. Keyak and Christopher M. Powers
and running. 7 – 9 With respect to running, Wirtz et al 8 reported that persons with PFP demonstrated similar peak patellofemoral joint stress when compared with pain-free individuals. However, several limitations of the study by Wirtz et al 8 call into question the biofidelity of the findings. For
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
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
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
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.
Kenneth D. Coutts
Nine male elite wheelchair athletes performed a continuous progressive exercise test on a wheelchair ergometer to determine peak oxygen uptake. Three were paraplegic distance track competitors (SCI–TR), three were amputee distance track athletes (AMP–TR), and three were paraplegic basketball players (SCI–BB). Analysis of variance indicated a significant difference in the relative peak oxygen uptake between the groups, with the SCI–TR and AMP–TR groups having higher values than the SCI–BB group. No group differences were found in age, mass, oxygen uptake, ventilation, heart rate, ventilatory equivalent for oxygen, and oxygen pulse at maximal exercise. The absence of the mass of the lower extremities in the AMP–TR group has a significant effect on peak oxygen uptake relative to body mass, and relative peak oxygen uptake differences between individual SCI–TR and AMP–TR athletes did not appear to reflect performance differences in actual distance track events.
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
Erin M.R. Bigelow, Niell G. Elvin, Alex A. Elvin and Steven P. Arnoczky
To determine whether peak vertical and horizontal impact accelerations were different while running on a track or on a treadmill, 12 healthy subjects (average age 32.8 ± 9.8 y), were fitted with a novel, wireless accelerometer capable of recording triaxial acceleration over time. The accelerometer was attached to a custom-made acrylic plate and secured at the level of the L5 vertebra via a tight fitting triathlon belt. Each subject ran 4 miles on a synthetic, indoor track at a self-selected pace and accelerations were recorded on three perpendicular axes. Seven days later, the subjects ran 4 miles on a treadmill set at the individual runner’s average pace on the track and the peak vertical and horizontal impact magnitudes between the track and treadmill were compared. There was no difference (P = .52) in the average peak vertical impact accelerations between the track and treadmill over the 4 mile run. However, peak horizontal impact accelerations were greater (P = .0012) on the track when compared with the treadmill. This study demonstrated the feasibility for long-term impact accelerations monitoring using a novel wireless accelerometer.
Edward C. Frederick and John L. Hagy
Nine subjects (6 males, 3 females) ranging in body mass from 90.9 to 45.5 kg ran repeated trials across a force platform while being filmed at 50 fps. The subjects ran five barefooted trials at each of three speeds: 3.35, 3.83, and 4.47 m · s−1. Force data were collected on-line and analyzed for the magnitude and temporal characteristics of the initial impact (Fz1) peak and the active (Fz2) peak of vertical ground reaction force (VGRF). Multiple regression and correlation analysis were used to study the relationship between the magnitudes of these kinetic data and kinematic and anthropometric data taken from the film and from measurements of the subjects. The results support the general conclusion that speed and, indirectly, body mass are significant effectors of the magnitudes of Fz1. In addition, other factors that correlate significantly with Fz1 are reciprocal ponderal index (RPI) and stature; half-stride length, step length, leg length, and vertical hip excursion during a half-stride cycle; and hip offset, contact angle, and dorsiflexion angle at contact. Body mass correlates highly with Fz2 (r = 0.95). Other significant factors correlating with Fz2 are RPI, stature, vertical hip excursion, dorsiflexion angle, hip offset, half-stride length, and step length. These data support earlier findings that speed and the effective mass of the leg at contact are important effectors of the magnitude of Fzl. In addition, the kinematic and anthropometric parameters that contribute significantly to the variability in Fzl and F are generally cross-correlated with body size and/or running speed.