RESUMO
Replacement of fluid losses (dehydration) during sports activities in the heat has been investigated with different beverages. Bovine milk has been recommended for post-exercise rehydration, but its use during exercise may provoke gastrointestinal disorders. This study compared voluntary fluid intake, hydration, and incidence and severity of gastrointestinal (GI) disorders during exercise in the heat under three conditions: no drink (ND), water (W), and skimmed lactose-free milk (SM). Sixteen physically active university students exercised at 32 °C and 70% RH for 90 min at 60-75% HRmax while drinking W or SM ad libitum, or ND assigned at random. A questionnaire explored possible GI disorders. Ad libitum intake was higher (p < 0.05) for water (1206.2 mL) than milk (918.8 mL). Dehydration showed significant differences for SM versus W and ND (W = 0.28% BM; SM = -0.07% BM; ND = 1.38% BM, p < 0.05). Urine volume was significantly higher (p < 0.05) in the W condition (W = 220.4 mL; SM = 81.3 mL; ND = 86.1 mL). Thick saliva, belching, and abdominal pain were higher for SM, but scores were low. Skimmed lactose-free milk is a suitable, effective alternative to be consumed as a hydration beverage during moderate-intensity cycling in the heat for 90 min.
Assuntos
Desidratação , Temperatura Alta , Animais , Humanos , Desidratação/prevenção & controle , Hidratação , Leite , ÁguaRESUMO
Resumen Metaanálisis: efectos de técnicas de preparación mental basadas en imaginería - hipnosis sobre flow y rendimiento deportivo. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 18(1), 1-31. El presente estudio tiene como objetivo examinar la efectividad de técnicas psicológicas de preparación mental basadas en imaginería o hipnosis sobre el estado de flow, el rendimiento deportivo y su relación mediante la técnica meta analítica. Se realizó la revisión de literatura en diez bases de datos durante los meses de agosto a octubre de 2017, de los cuales se incluyeron 17 estudios relacionados con actividades deportivas y estudios que presentan mediciones pretest y postest. Se analizó un TE con diferencia de medias bajo modelo aleatorio. Se obtuvo un total de 53 tamaños de efecto (TE) para estado de flow y 62 tamaños de efecto (TE) para rendimiento. Se encontró un TE positivo para el estado de flow (TE= .782; n=52; .< .001) y para el rendimiento (TE= .339; n=60; .<.05). Se comprobó la relación positiva entre las dos variables (.= .312; .<.05); se establecieron las variables más relevantes que moderan el tamaño de efecto del estado de flow y el rendimiento: edad, años de experiencia deportiva, sexo. Se concluyó que la imaginería es la técnica psicológica más efectiva para incrementar el estado de flow y el rendimiento, se recomienda realizar investigaciones con diseño experimental puro y contemplar la medición multidimensional del estado de flow.
Abstract Meta-analysis: effects of mental preparation techniques based on imagery - hypnosis on flow states and athletic performance. PENSAR EN MOVIMIENTO: Revista de Ciencias del Ejercicio y la Salud, 18(1), 1-14. The present study aims to examine the effectiveness of psychological mental preparation techniques based on imagery or hypnosis on the state of flow, sports performance, and their relationship using the meta-analytic technique. A literature review was conducted in ten databases from August to October 2017, which resulted in 17 studies related to sports activities with pretest-posttest measurements. The Effect Size (ES) of mean difference was analyzed using a random model. A total of 53 ESs and 62 ESs were obtained for flow states and performance, respectively. A positive ES was found for the flow state (ES = .782, n = 52, p <.001) and for performance (ES = .339; n = 60; p <.05), and a positive relationship was verified between the two variables (ρ = .312, p <.05). The most relevant variables that moderate the effect size of the flow state and performance are age, years of sports experience, and sex. It is concluded that imagery is the most effective psychological technique to increase the state of flow and performance. Further research with a pure experimental design considering the multi-dimensional measurement of the state of flow is recommended.
