Search Results

You are looking at 91 - 100 of 3,456 items for :

  • "enhancements" x
Clear All
Restricted access

Martin J. Barwood, Jo Corbett, John Feeney, Paul Hannaford, Dan Henderson, Ian Jones and Jade Kirke

Purpose:

To establish the thermal and performance effects of wearing a lower-body graduated compression garment (GCG) in a hot environment (35.2°C ± 0.1°C) with a representative radiant heat load (~800 W/m2) in contrast to a control (running shorts) and sham condition (a compression garment 1 size larger than that recommended by the manufacturer), with the latter included to establish any placebo effect.

Method:

Eight participants (mean ± SD; age 21 ± 2 y, height 1.77 ± 0.06 m, mass 72.8 ± 7.1 kg, surface area, 1.89 ± 0.10 m2) completed 3 treadmill tests at a fixed speed for 15 min followed by a self-paced 5-km time trial. Performance (completion time) and pacing (split time), thermal responses (aural, skin, and mean body temperature, cardiac frequency), and perceptual responses (rating of perceived exertion [RPE], thermal sensation, thermal comfort) were measured.

Results:

Performance in the compression group was not different than in either sham or control at any stage (P > .05); completion time 26.08 ± 4.08, 26.05 ± 3.27, and 25.18 ± 3.15 min, respectively. At the end of the 5-km time trial, RPE was not different; it was 19 ± 1 across conditions. In general, thermal and perceptual responses were not different, although the radiant heat load increased site-specific skin temperature (quadriceps) in the garment conditions.

Conclusion:

GCG did not enhance performance in a hot environment with a representative radiant heat load. The sham treatment did not benefit perception. GCG provided no evidence of performance enhancement.

Restricted access

Daniel Erlacher and Michael Schredl

Nocturnal dreams can be considered as a kind of simulation of the real world on a higher cognitive level. Within lucid dreams, the dreamer is able to control the ongoing dream content and is free to do what he or she wants. In this pilot study, the possibility of practicing a simple motor task in a lucid dream was studied. Forty participants were assigned to a lucid dream practice group, a physical practice group and a control group. The motor task was to toss 10-cent coins into a cup and hit as many as possible out of 20 tosses. Waking performance was measured in the evening and on the next morning by the participants at home. The 20 volunteers in the lucid dream practice group attempted to carry out the motor task in a lucid dream on a single night. Seven participants succeeded in having a lucid dream and practiced the experimental task. This group of seven showed a significant improvement in performance (from 3.7 to 5.3); the other 13 subjects showed no improvement (from 3.4 to 2.9). Comparing all four groups, the physical practice group demonstrated the highest enhancement in performance followed by the successful lucid dream practice group. Both groups had statistically significant higher improvements in contrast to the nondreaming group and the control group. Even though the experimental design is not able to explain if specific effects (motor learning) or unspecific effects (motivation) caused the improvement, the results of this study showed that rehearsing in a lucid dream enhances subsequent performance in wakefulness. To clarify the factors which increased performance after lucid dream practice and to control for confounding factors, it is suggested that sleep laboratory studies should be conducted in the future. The possibilities of lucid dream practice for professional sports will be discussed.

Restricted access

César Gallo-Salazar, Francisco Areces, Javier Abián-Vicén, Beatriz Lara, Juan José Salinero, Cristina Gonzalez-Millán, Javier Portillo, Victor Muñoz, Daniel Juarez and Juan Del Coso

The aim of this study was to investigate the effectiveness of a caffeinated energy drink to enhance physical performance in elite junior tennis players. In 2 different sessions separated by 1 wk, 14 young (16 ± 1 y) elite-level tennis players ingested 3 mg caffeine per kg body mass in the form of an energy drink or the same drink without caffeine (placebo). After 60 min, participants performed a handgrip-strength test, a maximal-velocity serving test, and an 8 × 15-m sprint test and then played a simulated singles match (best of 3 sets). Instantaneous running speed during the matches was assessed using global positioning (GPS) devices. Furthermore, the matches were videotaped and notated afterward. In comparison with the placebo drink, the ingestion of the caffeinated energy drink increased handgrip force by ~4.2% ± 7.2% (P = .03) in both hands, the running pace at high intensity (46.7 ± 28.5 vs 63.3 ± 27.7 m/h, P = .02), and the number of sprints (12.1 ± 1.7 vs 13.2 ± 1.7, P = .05) during the simulated match. There was a tendency for increased maximal running velocity during the sprint test (22.3 ± 2.0 vs 22.9 ± 2.1 km/h, P = .07) and higher percentage of points won on service with the caffeinated energy drink (49.7% ± 9.8% vs 56.4% ± 10.0%, P = .07) in comparison with the placebo drink. The energy drink did not improve ball velocity during the serving test (42.6 ± 4.8 vs 42.7 ± 5.0 m/s, P = .49). The preexercise ingestion of caffeinated energy drinks was effective to enhance some aspects of physical performance of elite junior tennis players.

Restricted access

Markus Tilp, Simon Steib, Gudrun Schappacher-Tilp and Walter Herzog

Force enhancement following muscle stretching and force depression following muscle shortening are well-accepted properties of skeletal muscle contraction. However, the factors contributing to force enhancement/depression remain a matter of debate. In addition to factors on the fiber or sarcomere level, fiber length and angle of pennation affect the force during voluntary isometric contractions in whole muscles. Therefore, we hypothesized that differences in fiber lengths and angles of pennation between force-enhanced/depressed and reference states may contribute to force enhancement/depression during voluntary contractions. The purpose of this study was to test this hypothesis. Twelve subjects participated in this study, and force enhancement/depression was measured in human tibialis anterior. Fiber lengths and angles of pennation were quantified using ultrasound imaging. Neither fiber lengths nor angles of pennation were found to differ between the isometric reference contractions and any of the force-enhanced or force-depressed conditions. Therefore, we rejected our hypothesis and concluded that differences in fiber lengths or angles of pennation do not contribute to the observed force enhancement/depression in human tibialis anterior, and speculate that this result is likely true for other muscles too.

Restricted access

Roy J. Shephard and Hughes Lavallée

The influence of 1 hour per day of required physical education upon aerobic fitness was tested in 546 prepubescent children recruited from an urban and a rural school in Québec. Two cohorts of experimental students began the enhanced program in Grade 1, with immediately preceding and succeeding classes as controls. V̇O2 peak (treadmill) and PWC170 were measured each year within 2 weeks of each child’s birthday. The data showed significant effects of sex (M>F) and environment (urban>rural). Experimental students showed a significant advantage of V̇O2 peak from 8 to 11 years (M>F; urban>rural). Many students reached less than a centrally limited V̇O2max, although the quality of peak effort was somewhat better in experimental than in control students. PWC170 values confirmed a training response in the boys but not in the girls. The data illustrate some of the problems of repeated testing of young children, but nevertheless support the value of training in the prepubescent years.

Restricted access

Josh Trout and Eddie Vela

In 2009, California State University-Chico implemented a unique system of course redesign with the aim of improving student learning, increasing instructional efficiency, and reducing university costs. Inspired by and modeled after the National Center for Academic Transformation, the “Academy e-Learning” program involves a 3-week training covering models of course design, learning theories, assessment methods, and a host of instructional technologies. This paper summarizes data from 40 courses, across five separate cohort groups from 2009–2013, with respect to the efficacy of Academy e-Learning (re)design training. Data show improvements in student learning outcomes in over half of the course redesigns. Benefits of course redesign included increased instructional efficiency, enhanced student learning, and a reduction in university costs by offering some instruction online and increasing enrollment caps. Barriers to a successful course redesign included lack of time, technology malfunction, and workload concerns. This paper outlines the redesign process at California State University-Chico, discusses similar redesign initiatives at other institutions, and offers solutions for measuring effectiveness of a redesigned course.

Restricted access

E. Dean Ryan and Jeff Simons

To investigate the mental imagery aspect of mental rehearsal, 80 male traffic officers from the California Highway Patrol learned a novel balancing task during a single session. Based on a pretest questionnaire, subjects were categorized as imagers, nonimagers, or occasional imagers and assigned to one of six groups accordingly: imagers asked to use imagery in mental rehearsal, imagers asked to try not to use imagery, nonimagers asked not to use imagery, nonimagers asked to try to use imagery, physical practice, or no practice. It was hypothesized that a person's preferred cognitive style would prove most effective for use in mental rehearsal and that using another style would cause a decrement in learning. Improvement scores indicated no differences between subjects who initially reported typically using imagery and those reported typically not using it, but groups asked to use imagery in mental rehearsal were superior to those asked not to (p<.001). Overall, physical practice was better than the grouped mental rehearsal conditions, and both were better than no practice. Subjects reporting strong visual imagery were superior to those with weak visual images (p<.03), and those reporting strong kinesthetic imagery were superior to those with weak kinesthetic images (p<.03). Regardless of one's typical cognitive style, the use of vivid imagery appears quite important for enhancement of motor performance through mental rehearsal.

Restricted access

Jim Wilcox, Rich Larson, Kevin M. Brochu and Avery D. Faigenbaum

Purpose:

The purpose of this investigation was to determine whether the performance of explosive-force movements before bench-press exercise would improve 1-repetition-maximum (1RM) strength.

Methods:

Twelve male college athletes participated in 3 testing sessions separated by at least 5 days of rest. During each testing session, the 1RM was assessed on the bench-press exercise. After a general warm-up, subjects performed a specific warm-up that consisted of submaximal sets with increasing loads on the bench-press exercise before attempting a 1RM lift. During the first testing trial, subjects performed a series of 1RM attempts with increasing loads until their 1RM was determined. During the second and third testing trials, subjects performed in a counterbalanced randomized order either 2 plyometric push-ups or 2 medicine-ball (3 to 5 kg) chest passes 30 seconds before each 1RM attempt.

Results:

Analysis of the data revealed that 1RM bench-press strength was significantly greater after plyometric push-ups (P = .004) or chest passes (P = .025) in comparison with the first trial (123.8 ± 23.5 kg and 124.0 ± 24.1 kg vs 120.9 ± 23.2 kg, respectively).

Conclusions:

These data suggest that an acute bout of low-volume, explosive-force upper body movements performed 30 seconds before a 1RM attempt might enhance bench-press performance in athletic men.

Restricted access

Daniel Gould, Ken Hedge, Kirsten Peterson and John Giannini

Two studies were conducted to assess strategies elite coaches use to enhance self-efficacy in athletes, in particular the degree to which coaches use 13 strategies to influence self-efficacy and their evaluation of the effectiveness of those strategies. Self-efficacy rating differences between categories of coaches were also examined. Intercollegiate wrestling coaches (iV=101) surveyed in Study 1 indicated they most often used instruction-drilling, modeling confidence oneself, encouraging positive talk, and employing hard physical conditioning drills. Techniques or strategies judged most effective by these coaches included instraction-drilling, modeling confidence oneself, liberal use of reward statements, and positive talk. In Study 2, 124 national team coaches representing 30 Olympic-family sports served as subjects. The strategies they most often used were instruction-drilling, modeling confidence oneself, encouraging positive talk, and emphasizing technique improvements while downplaying outcome. The techniques judged most effective were instruction-drilling, encouraging positive talk, modeling confidence onself, and liberal use of reward statements. Few between-coach differences were found in efficacy use and effectiveness ratings. Findings are discussed in light of Bandura's (1977) theory of self-efficacy.

Restricted access

Rachel W. Thompson, Keith A. Kaufman, Lilian A. De Petrillo, Carol R. Glass and Diane B. Arnkoff

The purpose of the present investigation was to evaluate the long-term effects of mindful sport performance enhancement (MSPE), a program designed to improve athletic performance and psychological aspects of sport. One-year follow-up assessments were conducted on archers, golfers, and long-distance runners (N = 25) who attended Kaufman, Glass, and Arnkoff’s (2009) and De Petrillo, Kaufman, Glass, and Arnkoff’s (2009) MSPE workshops. Across the athlete groups, participants reported significant increases in the ability to act with awareness (an aspect of trait mindfulness) and overall trait mindfulness from pretest to follow-up, along with significant decreases in task-related worries and task-irrelevant thoughts (both aspects of cognitive interference during sport). The long-distance runners exhibited significant improvement in their mile times from pretest to follow-up, with significant correlations between change in runners’ performance and trait variables. Results suggest that MSPE is a promising intervention associated with long-term changes in trait variables that may contribute to optimal athletic performance.