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1.
PLoS One ; 18(3): e0280201, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36862750

RESUMEN

PURPOSE: The way coaching cues are worded can impact on the quality with which a subsequent motor skill is executed. However, there have been few investigations on the effect of coaching cues on basic motor skill performance in youths. METHOD: Across several international locations, a series of experiments were undertaken to determine the effect of external coaching cues (EC), internal coaching cues (IC), analogies with a directional component (ADC) and neutral control cues on sprint time (20 m) and vertical jump height in youth performers. These data were combined using internal meta-analytical techniques to pool results across each test location. This approach was amalgamated with a repeated-measures analysis to determine if there were any differences between the ECs, ICs and ADCs within the different experiments. RESULTS: 173 participants took part. There were no differences between the neutral control and experimental cues in any of the internal meta-analyses except where the control was superior to the IC for vertical jump (d = -0.30, [-0.54, -0.05], p = 0.02). Just three of eleven repeated-measures analyses showed significant differences between the cues at each experimental location. Where significant differences were noted, the control cue was most effective with some limited evidence supporting the use of ADCs (d = 0.32 to 0.62). CONCLUSION: These results suggest the type of cue or analogy provided to a youth performer has little subsequent effect on sprint or jump performance. Accordingly, coaches might take a more specific approach that is suited to the level or preferences of a particular individual.


Asunto(s)
Vacunas contra el Cáncer , Tutoría , Adolescente , Humanos , Señales (Psicología) , Destreza Motora , Vehículos a Motor
2.
Pediatr Exerc Sci ; 34(3): 162-167, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35259723

RESUMEN

PURPOSE: To assess the training load, energy expenditure, dietary intake, and sleep quality and quantity of junior tennis players during a tennis training camp. METHODS: Ten junior academy tennis players (14 [1] y) completed a 6-day camp with daily morning and afternoon training. Players wore accelerometer watches to measure activity energy expenditure and sleep. Global positioning system units were worn to monitor external training load (distance covered, maximum velocity, and PlayerLoad™). Dietary intake was obtained from a food diary and supplementary food photography. RESULTS: Players covered significantly more distance and had higher PlayerLoad™ during morning sessions than afternoon sessions (5370 [505] m vs 4726 [697] m, P < .005, d = 3.2; 725 [109] a.u. vs 588 [96] a.u., P < .005, d = 4.0). Players also ran further (5624 [897] m vs 4933 [343] m, P < .05, d = 1.0) and reached higher maximum velocities (5.17 [0.44] m·s-1 vs 4.94 [0.39] m·s-1, P < .05, d = 0.3) during simulated match play compared with drill sessions. Mean daily energy expenditure was 3959 (630) kcal. Mean energy intake was 2526 (183) kcal, resulting in mean energy deficits of 1433 (683) kcal. Players obtained an average of 6.9 (0.8) hours of sleep and recorded 28 (7) nightly awakenings. CONCLUSIONS: Junior academy tennis players failed to achieve energy balance and recorded suboptimal sleep quantity and quality throughout the training camp.


Asunto(s)
Tenis , Registros de Dieta , Ingestión de Energía , Sistemas de Información Geográfica , Humanos , Sueño
3.
J Immunol ; 178(5): 2679-87, 2007 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17312109

RESUMEN

The decision to generate a productive immune response or immune tolerance following pathogenic insult often depends on the context in which T cells first encounter Ag. The presence of apoptotic cells favors the induction of tolerance, whereas immune responses generated with necrotic cells promote immunity. We have examined the tolerance induced by injection of apoptotic cells, a system in which cross-presentation of Ag associated with the dead cells induces CD8+ regulatory (or suppressor) T cells. We observed that haptenated apoptotic cells induced CD8+ suppressor T cells without priming CD4+ T cells for immunity. These CD8+ T cells transferred unresponsiveness to naive recipients. In contrast, haptenated necrotic cells stimulated immunity, but induced CD8+ suppressor T cells when CD4+ T cells were absent. We further found that CD8+ T cells induced by these treatments displayed a "helpless CTL" phenotype and suppress the immune response by producing TRAIL. Animals deficient in TRAIL were resistant to tolerance induction by apoptotic cells. Thus, the outcome of an immune response taking place in the presence of cell death can be determined by the presence of CD4+-mediated Th cell function.


Asunto(s)
Apoptosis/inmunología , Tolerancia Inmunológica , Ligando Inductor de Apoptosis Relacionado con TNF/inmunología , Animales , Presentación de Antígeno/inmunología , Antígenos/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos , Ratones , Ratones Noqueados , Necrosis/inmunología , Ligando Inductor de Apoptosis Relacionado con TNF/deficiencia
4.
Arch Sex Behav ; 34(6): 691-705, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16362253

RESUMEN

Cognitive-behavioral psychotherapy was compared with cognitive-behavioral psychotherapy augmented by leuprolide acetate (LA) for suppression of pedophilic behavior. Five male pedophiles (M age, 50 years; range, 36-58) were administered LA by Depo injection for 12 months, followed by saline placebo for 12 months. Testosterone levels, sexual interest preference by visual reaction time (Abel Assessment), penile tumescence (Monarch Penile Plethysmography, PPG), as well as strong sexual urges toward children and masturbatory frequency involving thoughts of children (polygraph), were measured every 3 months. On LA, testosterone decreased to castrate levels. Penile tumescence was significantly suppressed compared with baseline, but sufficient response remained to detect pedophilic interest. Pedophilic interest was also detected by visual reaction times. When asked about having pedophilic urges and masturbating to thoughts of children, all subjects self-reported a decrease. Polygraph responses indicated subjects were not deceptive. On placebo, testosterone and physiologic arousal eventually rose to baseline. As noted by polygraph, at baseline and on placebo, subjects were deceptive regarding increased pedophilic urges and masturbatory frequency. Interest preference, as measured by Abel Assessment and Monarch PPG, was generally unchanged throughout the study. Cognitive-behavioral psychotherapy augmented with LA significantly reduced pedophilic fantasies, urges, and masturbation; however, pedophilic interest did not change during 1 year of therapy. Deceptive responses by polygraph suggested that self-report was unreliable. Follow-up utilizing objective measures is essential for monitoring efficacy of treatment in pedophilia. Our study supports the premise that suppression of pedophilic behavior is possible. LA may augment cognitive-behavioral psychotherapy and help break the sequence leading to a re-offense.


Asunto(s)
Leuprolida/administración & dosificación , Pedofilia/tratamiento farmacológico , Conducta Sexual/efectos de los fármacos , Adulto , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Hormona Folículo Estimulante/sangre , Humanos , Leuprolida/efectos adversos , Libido/efectos de los fármacos , Masculino , Persona de Mediana Edad , Pedofilia/sangre , Pedofilia/psicología , Erección Peniana/efectos de los fármacos , Prolactina/sangre , Estudios Prospectivos , Testosterona/sangre , Resultado del Tratamiento
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