Thomas F. Gilbert     

Peter Dean 《Performance Improvement》1995,34(10):4-5

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Some basics about ethics     

Peter J. Dean 《Performance Improvement》1994,33(10):42-45

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The relationship between adaptive behavior and intelligence for special needs students     

Salvatore Terrasi  Peter W. Airasian 《Psychology in the schools》1989,26(2):202-208

This study employed the technique of factor analysis to study the relationship between social system adaptive behavior, as measured by the Adaptive Behavior Inventory for Children, and intelligence, as measured by the Wechsler Intelligence Scale for Children-Revised, in a sample of 100 special needs students, ages 6–11. The results clearly supported the existence of two distinct factors among the WISC-R and ABIC subscales, with each factor composed primarily of either intelligence or adaptive behavior subscales. Thus, the data supported the discriminant validity of the two measures. Implications for the evaluation of special needs students are discussed.  相似文献   

The effect of beetroot juice supplementation on repeat-sprint performance in hypoxia     

Georgina L. Kent  Brian Dawson  Lars R. McNaughton  Gregory R. Cox  Louise M. Burke  Peter Peeling 《Journal of sports sciences》2019,37(3):339-346

This investigation assessed the effect of dietary nitrate (NO₃^?) supplementation, in the form of beetroot juice (BR), on repeat-sprint performance in normoxia and normobaric hypoxia. 12 male team-sport athletes (age 22.3 ± 2.6 y, VO_2peak 53.1 ± 8.7 mL.kg^?1.min^?1) completed three exercise trials involving a 10 min submaximal warm-up and 4 sets of cycling repeat-sprint efforts (RSE; 9 × 4 s) at sea level (CON), or at 3000 m simulated altitude following acute supplementation (140 mL) with BR (HYP_BR; 13 mmol NO₃^?) or NO₃^–depleted BR placebo (HYP_PLA). Peak (PPO) and mean (MPO) power output, plus work decrement were recorded during the RSE task, while oxygen consumption (VO₂) was measured during the warm-up. There were no significant differences observed between HYP_BR and HYP_PLA for PPO or MPO; however, work decrement was reduced in the first RSE set in HYP_BR compared with HYP_PLA. There was a moderate effect for VO₂ to be lower following BR at the end of the 10 min warm-up (ES = 0.50 ± 0.51). Dietary NO₃^? may not improve repeat-sprint performance in hypoxia but may reduce VO₂ during submaximal exercise. Therefore, BR supplementation may be more effective for performance improvement during predominantly aerobic exercise.  相似文献   

Understanding the track and field sprint start through a functional analysis of the external force features which contribute to higher levels of block phase performance     

Neil Edward Bezodis  Sean Peter Walton  Ryu Nagahara 《Journal of sports sciences》2019,37(5):560-567

This study aimed to identify the continuous ground reaction force (GRF) features which contribute to higher levels of block phase performance. Twenty-three sprint-trained athletes completed starts from their preferred settings during which GRFs were recorded separately under each block. Continuous features of the magnitude and direction of the resultant GRF signals which explained 90% of the variation between the sprinters were identified. Each sprinter’s coefficient score for these continuous features was then input to a linear regression model to predict block phase performance (normalised external power). Four significant (p < 0.05) predictor features associated with GRF magnitude were identified; there were none associated with GRF direction. A feature associated with greater rear block GRF magnitudes from the onset of the push was the most important predictor (β = 1.185), followed by greater front block GRF magnitudes for the final three-quarters of the push (β = 0.791). Features which included a later rear block exit (β = 0.254) and greater front leg GRF magnitudes during the mid-push phase (β = 0.224) were also significant predictors. Sprint practitioners are encouraged, where possible, to consider the continuous magnitude of the GRFs produced throughout the block phase in addition to selected discrete values.  相似文献   

Evening electronic device use and sleep patterns in athletes     

Maddison J. Jones  Brian Dawson  Daniel F. Gucciardi  Peter R. Eastwood  Joanna Miller  Shona L. Halson 《Journal of sports sciences》2019,37(8):864-870

The present study aimed to investigate pre-sleep behaviours (including evening electronic device use) and sleep quantity in well-trained athletes. Seventy well-trained athletes (44 females, 26 males) aged 21 ± 4 y from a range of team and individual sports were asked to complete an online sleep diary for 7 days. The sleep diary included questions about pre-sleep behaviours (e.g. napping, caffeine intake), electronic device use in the 2 h prior to bedtime (e.g. type of device and duration of use) and sleep (e.g. time in bed, sleep onset latency). On average, athletes spent 8:20 ± 1:21 h in bed each night. Associations between age, time in bed and sleepiness suggested that younger athletes spent more time in bed (B = -0.05, p = 0.001) but felt sleepier (r = -0.32, p < 0.01) than older athletes. On average, athletes mostly used electronic devices for 0–30 min prior to sleep. The use of multiple devices in the evening was associated with more perceived difficulty in falling asleep (B = 0.22, p = 0.03), but no associations existed with other sleep variables. In summary, younger athletes may require later start times or improved sleep quality to resolve excessive sleepiness.  相似文献   

Static and dynamic accuracy of a magnetic-inertial measurement unit used to provide racket swing kinematics     

Benjamin Kane Williams  Ross H. Sanders  Joong Hyun Ryu  Pitre C. Bourdon  Philip Graham-Smith  Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):202-214

Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics.  相似文献   

The application of inertial measurement units and functional principal component analysis to evaluate movement in the forward 3½ pike somersault springboard dive     

Cherie Walker  John Warmenhoven  Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):146-162

Based on technological and analytical advances, the capability to more accurately and finitely examine biomechanical and skill characteristics of movement has improved. The purpose of this study was to use Inertial Measurement Units (IMUs) and Functional Principal Components Analysis (fPCA) to examine the role of movement variability (assessed via angular velocity), on 2 divers (1 international level; 1 national) performing the forward 3½ pike somersault dive. Analysis of angular velocity curves during ive-flight identified 5 fPCs, accounting for 96.5% of movement variability. The national diver’s scatter plots and standard deviation of fPC scores illustrated larger magnitudes of angular velocity variability across dive flight. For fPC1 and fPC3, magnitudes of SD variability were 282.6 and 201.5, respectively. The international diver illustrated more consistent angular velocity profiles, with clustering of fPCs scores (e.g., fPC1 & 3 = SD’s of 75.2 & 68.0). To account for lower variability in the international diver, the ability to better coordinate movement sequences and functionally utilise feedback in response to initiation of the somersault position is highlighted. Overall, findings highlight how both IMUs and fPCA can more holistically and finitely examine the biomechanical and skill characteristics of movement sequences with the capability to inform athlete development.  相似文献   

Virtual-reality exergaming improves performance during high-intensity interval training     

Matthew Farrow  Christof Lutteroth  Peter C. Rouse 《European Journal of Sport Science》2019,19(6):719-727

Purpose: To determine if: (i) mean power output and enjoyment of high-intensity interval training (HIIT) are enhanced by virtual-reality (VR)-exergaming (track mode) compared to standard ergometry (blank mode), (ii) if mean power output of HIIT can be increased by allowing participants to race against their own performance (ghost mode) or by increasing the resistance (hard mode), without compromising exercise enjoyment.

Methods: Sixteen participants (8 males, 8 females, VO₂max: 41.2?±?10.8 ml^?1·kg^?1·min^?1) completed four VR-HIIT conditions in a partially-randomised cross-over study; (1a) blank, (1b) track, (2a) ghost, and (2b) hard. VR-HIIT sessions consisted of eight 60 s high-intensity intervals at a resistance equivalent to 70% (77% for hard) maximum power output (P_MAX), interspersed by 60 s recovery intervals at 12.5% P_MAX, at a self-selected cadence. Expired gases were collected and VO₂ measured continuously. Post-exercise questionnaires were administered to identify differences in indices related to intrinsic motivation, subjective vitality, and future exercise intentions.

Results: Enjoyment was higher for track vs. blank (difference: 0.9; 95% CI: 0.6, 1.3) with no other differences between conditions. There was no difference in mean power output for track vs. blank, however it was higher for track vs. ghost (difference: 5 Watts; CI: 3, 7), and hard vs. ghost (difference: 19 Watts; 95% CI: 15, 23).

Conclusions: These findings demonstrate that VR-exergaming is an effective intervention to increase enjoyment during a single bout of HIIT in untrained individuals. The presence of a ghost may be an effective method to increase exercise intensity of VR-HIIT.  相似文献   

‘We Have to Go Where the Money Is’—Dilemmas in the Role of Nutrition Scientists: An Interview Study     

Anna Paldam Folker  Lotte Holm  Peter Sandøe 《Minerva》2009,47(2):217-236

In Western societies scientists are increasingly expected to seek media exposure and cooperate with industry. Little attention has been given to the way such expectations affect the role of scientific experts in society. To investigate scientists’ own perspectives on these issues eight exploratory, in-depth interviews were conducted in Denmark with reputable nutrition scientists. Additionally, eight interviews were held with ‘key informants’ from the field of nutrition policy. It was found that nutrition scientists experience two dilemmas: first, between their aspiration to make a collective impact on public health and the powerful incentives of each to appear frequently in the media with new messages; second, between their need to cooperate with the food industry for financial reasons and their fear that this may compromise their independence and scientific integrity. It is argued that the dilemmas identified in this study should be dealt with openly by the relevant groups of scientists.  相似文献