Search Results

You are looking at 1 - 10 of 28 items for

  • Author: James Stephens x
  • Refine by Access: All Content x
Clear All Modify Search
Restricted access

James Stephens and Susan Hillier

The Feldenkrais method (FM) is a process that uses verbally and manually guided exploration of novel movements to improve individuals’ self-awareness and coordination. This paper reviews recent literature evaluating the therapeutic value of the FM for improving balance, mobility, and coordination and its effectiveness for management of chronic pain. The authors also explore and discuss studies that have investigated some of the other bodily effects and possible mechanisms of action, such as (a) the process of learning itself, (b) focus of attention during motor learning, (c) autonomic regulation, and (d) body image. They found that research clearly supports the effectiveness of the FM for improvement of balance and chronic pain management. The exploration into mechanisms of action raises interesting questions and possibilities for further investigation.

Restricted access

James A. Yaggie and Stephen J. Kinzey

Context:

Ankle bracing has been used for many years in an attempt to prevent lateral ligamentous injuries of the ankle by restricting joint range of motion (ROM).

Objective:

To examine the influence of ankle bracing on ROM and sport-related performance.

Design:

Repeated measures.

Setting:

Biomechanics laboratory.

Participants:

30 volunteers. None reported ankle trauma within 2 years preceding the study or had other orthopedic conditions that would have affected physical performance.

Intervention:

Three brace conditions (McDavid A101™, Perform-8™ Lateral Stabilizer) were assessed during performance of the vertical jump and shuttle run.

Main Outcome Measures:

shuttle-run time, vertical jump height, inversion, and plantar flexion ROM.

Results:

Both braces restricted plantar flexion and inversion ROM and caused no change in shuttle-run time or vertical jump height.

Conclusions:

Our results indicate that bracing the ankle joint increases external lateral support to the joint without significantly restricting functional ability.

Restricted access

Scott C. Wearing, James E. Smeathers, and Stephen R. Urry

Studies investigating the effect of targeting on gait have focused on the analysis of ground reaction force (GRF) within the time domain. Analysis within the frequency domain may be a more sensitive method for evaluating variations in GRF. The aim of the present study was to investigate the effect of visual targeting on GRF analyzed within the frequency domain. A within-subject repeated-measures design was used to measure the mediolateral, vertical, and antero-posterior components of the GRF of 11 healthy volunteers while walking at their own pace over a paper-covered walkway. A 30 × 24-cm target area was superimposed over a hidden Kistler force plate mounted at the midpoint of the walkway. GRF were recorded with and without the target and were analyzed within the frequency domain. Although visually guided foot placement has previously been undetected by traditional time-domain measures, targeting was found to significantly increase the frequency content of both the mediolateral (t10 = -4.07, p < 0.05) and antero-posterior (t10 = -2.52, p < 0.05) components of GRF. Consequently, it appears that frequency analysis is a more sensitive analytic technique for evaluating GRF. These findings have methodological implications for research in which GRF is used to characterize and assess anomalies in gait patterns.

Restricted access

C. Mark Woodard, Margaret K. James, and Stephen P. Messier

Our purpose was to compare methods of calculating loading rate to the first peak vertical ground reaction force during walking and provide a rationale for the selection of a loading rate algorithm in the analysis of gait in clinical and research environments. Using vertical ground reaction force data collected from 15 older adults with symptomatic knee osteoarthritis and 15 healthy controls, we: (a) calculated loading rate as the first peak vertical force divided by the time from touchdown until the first peak; (b) calculated loading rate as the slope of the least squares regression line using vertical force and time as the dependent and independent variables, respectively; (c) calculated loading rate over discrete intervals using the Central Difference method; and (d) calculated loading rate using vertical force and lime data representing 20% and 90% of the first peak vertical force. The largest loading rate, which may be of greatest clinical importance, occurred when loading rates were calculated using the fewest number of data points. The Central Difference method appeared to maximize our ability to detect differences between healthy and pathologic cohorts. Finally, there was a strong correlation between methods, suggesting that all four methods are acceptable. However, if maximizing the chances of detecting differences between groups is of primary importance, the Central Difference method appears superior.

Restricted access

Andy Galbraith, James Hopker, Stephen Lelliott, Louise Diddams, and Louis Passfield

Purpose:

To compare critical speed (CS) measured from a single-visit field test of the distance–time relationship with the “traditional” treadmill time-to-exhaustion multivisit protocol.

Methods:

Ten male distance runners completed treadmill and field tests to calculate CS and the maximum distance performed above CS (D′). The field test involved 3 runs on a single visit to an outdoor athletics track over 3600, 2400, and 1200 m. Two field-test protocols were evaluated using either a 30-min recovery or a 60-min recovery between runs. The treadmill test involved runs to exhaustion at 100%, 105%, and 110% of velocity at VO2max, with 24 h recovery between runs.

Results:

There was no difference in CS measured with the treadmill and 30-min- and 60-minrecovery field tests (P < .05). CS from the treadmill test was highly correlated with CS from the 30- and 60-min-recovery field tests (r = .89, r = .82; P < .05). However there was a difference and no correlation in D′ between the treadmill test and the 30 and 60-min-recovery field tests (r = .13; r = .33, P > .05). A typical error of the estimate of 0.14 m/s (95% confidence limits 0.09–0.26 m/s) was seen for CS and 88 m (95% confidence limits 60–169 m) for D′. A coefficient of variation of 0.4% (95% confidence limits: 0.3–0.8%) was found for repeat tests of CS and 13% (95% confidence limits 10–27%) for D′.

Conclusion:

The single-visit method provides a useful alternative for assessing CS in the field.

Restricted access

Stephen D. Ross, Jeffrey D. James, and Patrick Vargas

The Team Brand Association Scale (TBAS), which is intended to measure professional sport team brand associations, was developed through the use of a free-thought listing technique in combination with a confirmatory factor analysis procedure. Information was provided by individuals regarding their favorite sports team, and 11 dimensions underlying professional sport team brand associations were identified: nonplayer personnel, team success, team history, stadium community, team play characteristics, brand mark, commitment, organizational attributes, concessions, social interaction, and rivalry. Review of the TBAS psychometric properties indicated that eight dimensions had acceptable reliabilities (Cronbach’s alpha scores ranging from .76-.90), as well as content validity (verified by a 3-member expert panel review), discriminant validity (based on correlations among latent constructs and their standard errors), concurrent validity (significant correlations with an external measure), and construct validity.

Restricted access

Elizabeth Y. Brown, James R. Morrow Jr., and Stephen M. Livingston

The purpose of the present study was to determine if completion of a 14-week conditioning course affected the physical and total self-concepts of college-age women. Analysis of variance was used to contrast experimental and control groups of 50 subjects each on selected subscales of the Tennessee Self Concept Scale. Results indicated that the women showed significant differences in self-concept upon completion of the conditioning program; however, effects were not generalizable to all dimensions of self-concept. Implications are that training programs may be beneficial in their impact on selected aspects of the self-concept of women as well as the physiological parameters typically affected by conditioning programs. Self-concept profiles are developed for those women who entered the program as well as for those who completed the program.

Full access

George P. Robinson, Sophie C. Killer, Zdravko Stoyanov, Harri Stephens, Luke Read, Lewis J. James, and Stephen J. Bailey

This study investigated whether supplementation with nitrate-rich beetroot juice (BR) can improve high-intensity intermittent running performance in trained males in normoxia and different doses of normobaric hypoxia. Eight endurance-trained males (V˙O2peak, 62 ± 6 ml·kg−1·min−1) completed repeated 90 s intervals at 110% of peak treadmill velocity, from an initial step incremental test, interspersed by 60 s of passive recovery until exhaustion (T lim). Participants completed the first three experimental trials during days 3, 5, and 7 of BR or nitrate-depleted beetroot juice (PLA) supplementation and completed the remaining experimental visits on the alternative supplement following at least 7 days of washout. The fraction of inspired oxygen during visits 1–3 was either 0.209, 0.182, or 0.157, equivalent to an altitude of 0, 1,200, and 2,400 m, respectively, and this order was replicated on visits 4–6. Arterial oxygen saturation declined dose dependently as fraction of inspired oxygen was lowered (p < .05). Plasma nitrite concentration was higher pre- and postexercise after BR compared with PLA supplementation (p < .05). There was no difference in Tlim between PLA and BR at 0 m (445 [324, 508] and 410 [368, 548] s); 1,200 m (341 [270, 390] and 332 [314, 356] s); or 2,400 m (233 [177, 373] and 251 [221, 323] s) (median and [interquartile range]; p > .05). The findings from this study suggest that short-term BR supplementation does not improve high-intensity intermittent running performance in endurance-trained males in normoxia or at doses of normobaric hypoxia that correspond to altitudes at which athletes typically train while on altitude training camps.

Restricted access

Joel B. Mitchell, James R. Rowe, Meena Shah, James J. Barbee, Austen M Watkins, Chad Stephens, and Steve Simmons

To examine the effect of prior exercise on the postprandial lipid response to a high-carbohydrate meal in normal-weight (NW = BMI h25) and overweight (OW = BMI ≥25) women (age 18–25), 10 NW and 10 OW participants completed 2 conditions separated by 1 month. In the morning, the day after control (CT = no exercise) or exercise conditions (EX = 60 min cycling at 60% VO2peak), participants consumed a high-carbohydrate meal (80% CHO, 15% protein, 5% fat; 75 kJ/kg BM) followed by 6 hr of hourly blood sampling. Blood was analyzed for triglycerides (TG), blood glucose (BG), and insulin (IN). TG levels over the 6-hr period were lower in NW than OW (p = .021) and lower in EX than in CT (p = .006). Area under the curve (AUC) for TG was lower in NW than OW (p = .016) and EX than CT (p = .003). There were nonsignificant tendencies for reduced BG over time (p = .053) and AUC (p = .083), and IN AUC was lower in EX than in CT (p = .040) for both groups and lower in NW than in OW (p = .039). Prior exercise improved TG levels after a high-carbohydrate meal in both groups, and OW women demonstrated a greater postprandial lipemic response than NW regardless of condition. There were tendencies for improved glucose removal with prior exercise in NW vs. OW. Acute exercise can improve postprandial TG responses and might also improve postprandial BG and IN after a large meal in NW and OW young women.

Restricted access

Jon N. Swift Jr., James P. Kehrer, K. Stephen Seiler, and Joseph W. Starnes

The purpose of this study was to determine whether submaximal exercise significantly changes the concentration of vitamin E (αToc) in rat liver and skeletal muscle and to establish a time course for the return to basal levels. Male Sprague-Dawley rats, age 8 to 10 weeks, were randomly divided into sedentary control (Con) (n = 7) and exercise n = 17) groups. Exercised animals ran 100 min on a motorized treadmill at approximately 70% VO2max for 3 consecutive days. They were then sacrificed immediately postexercise (0Post), 24 hr post (24Post), or 72 hr post (72Post). The gastrocnemius, red vastus lateralis (RV), white vastus lateralis (WV), and liver were excised and analyzed for αToc concentration by high-performance liquid chromolography utilizing electrochemical detection. We found that after 3 consecutive days of exercise, αToc was reduced in RV and WV at 0Post and 24Post but returned to control values by 72Post. Liver αToc content was not changed at OPost but was significantly reduced at 24 Post and 72 Post. No significant changes in αToc were observed in the gastrocnemius in response to exercise. The data indicate that following an exercise-related decrease, skeletal muscle vitamin E concentration requires more than 24 hr to return to the preexercise concentration, and that the replenishment process may involve redistribution of vitamin E from liver to muscle.