Effect of Supplementation of a Whey Peptide Rich in Tryptophan-Tyrosine-Related Peptides on Cognitive Performance in Healthy Adults: A Randomized, Double-Blind, Placebo-Controlled Study.

Background: Previous epidemiological and clinical studies have shown that dairy products have beneficial effects on cognitive decline and dementia. Enzymatic digestion of whey protein produces a whey peptide rich in tryptophan-tyrosine-related peptides which improve cognitive performance in mice. We evaluated the effects of whey peptides on cognitive functions in healthy adults in a randomized, double-blind, placebo-controlled design. Methods: 101 healthy adults (45 to 64 years), with a self-awareness of cognitive decline received either whey peptide or placebo supplements for 12 weeks. Changes in cognitive function were assessed using neuropsychological tests at 6 and 12 weeks after the start of supplementation. Results: Verbal fluency test (VFT) score changes tended to be higher in the whey peptide group compared with the placebo at 12 weeks. Subgroup analysis classified by the degree of subjective fatigue showed that changes in the VFT as well as the Stroop and subjective memory function tests between baseline and 6 weeks of intervention were significantly better in subjects with high-level fatigue from the whey peptide group as compared to the placebo group. CONCLUSIONS: Intake of whey peptide might improve cognitive function in healthy middle- and older-aged adults with high subjective fatigue levels. Further studies will elucidate the relationship among cognitive improvement, whey peptides, and psychological fatigue.

Protein Supplementation During or Following a Marathon Run Influences Post-Exercise Recovery.

The effects of protein supplementation on the ratings of energy/fatigue, muscle soreness [ascending (A) and descending (D) stairs], and serum creatine kinase levels following a marathon run were examined. Variables were compared between recreational male and female runners ingesting carbohydrate + protein (CP) during the run (CPDuring, n = 8) versus those that were consuming carbohydrate (CHODuring,n = 8). In a second study, outcomes were compared between subjects who consumed CP or CHO immediately following exercise [CPPost (n = 4) versus CHOPost (n = 4)]. Magnitude-based inferences revealed no meaningful differences between treatments 24 h post-marathon. At 72 h, recovery [Δ(72 hr-Pre)] was likely improved with CPDuring versus CHODuring, respectively, for Physical Energy (+14 ± 64 vs -74 ± 70 mm), Mental Fatigue (-52 ± 59 vs +1 ± 11 mm), and Soreness-D (+15 ± 9 vs +21 ± 70 mm). In addition, recovery at 72 h was likely-very likely improved with CPPost versus CHOPost for Physical Fatigue, Mental Energy, and Soreness-A. Thus, protein supplementation did not meaningfully alter recovery during the initial 24 h following a marathon. However, ratings of energy/fatigue and muscle soreness were improved over 72 h when CP was consumed during exercise, or immediately following the marathon.

Investigating the effects of caffeine on executive functions using traditional Stroop and a new ecologically-valid virtual reality task, the Jansari assessment of Executive Functions (JEF(©)).

OBJECTIVE: Caffeine has been shown to have effects on certain areas of cognition, but in executive functioning the research is limited and also inconsistent. One reason could be the need for a more sensitive measure to detect the effects of caffeine on executive function. This study used a new non-immersive virtual reality assessment of executive functions known as JEF(©) (the Jansari Assessment of Executive Function) alongside the 'classic' Stroop Colour-Word task to assess the effects of a normal dose of caffeinated coffee on executive function. METHOD: Using a double-blind, counterbalanced within participants procedure 43 participants were administered either a caffeinated or decaffeinated coffee and completed the 'JEF(©)' and Stroop tasks, as well as a subjective mood scale and blood pressure pre- and post condition on two separate occasions a week apart. JEF(©) yields measures for eight separate aspects of executive functions, in addition to a total average score. RESULTS: Findings indicate that performance was significantly improved on the planning, creative thinking, event-, time- and action-based prospective memory, as well as total JEF(©) score following caffeinated coffee relative to the decaffeinated coffee. The caffeinated beverage significantly decreased reaction times on the Stroop task, but there was no effect on Stroop interference. CONCLUSION: The results provide further support for the effects of a caffeinated beverage on cognitive functioning. In particular, it has demonstrated the ability of JEF(©) to detect the effects of caffeine across a number of executive functioning constructs, which weren't shown in the Stroop task, suggesting executive functioning improvements as a result of a 'typical' dose of caffeine may only be detected by the use of more real-world, ecologically valid tasks.

Effect of dried-bonito broth on mental fatigue and mental task performance in subjects with a high fatigue score.

Dried-bonito broth is commonly employed as a soup and sauce base in Japanese cuisine and is considered to be a nutritional supplement that promotes recovery from fatigue. Previous human trials suggest that the ingestion of dried-bonito broth improves several mood states; however, its effect on fatigue has not yet been clarified. The aim of this study was to clarify the effects of daily ingestion of dried-bonito broth on fatigue and cognitive parameters by a placebo-controlled double blind crossover trial. Forty-eight subjects with fatigue symptoms ingested the dried-bonito broth or a placebo solution every day for 4 weeks. Mood states were evaluated by the Profile of Mood States (POMS), and mental task performance was evaluated by the Uchida-Kraepelin psychodiagnostic (UKP) test. Fatigue and total mood disturbance (TMD) scores on the POMS test decreased significantly during the dried-bonito broth ingestion (p<0.05), but did not change significantly during placebo ingestion. The change in vigor score during dried-bonito broth ingestion was significantly higher than that during placebo ingestion at 2 weeks (p<0.05). The results of the UKP test indicate that the numbers of both total answers and correct answers significantly increased during dried-bonito broth ingestion (p<0.05), while no significant changes were observed in the placebo ingestion. These results suggest that the daily ingestion of dried-bonito broth may improve the mood states, may reduce mental fatigue and may increase performance on a simple calculation task.

Fatiga laboral en controladores de tránsito aéreo / Labor fatigue in air traffic controllers

El objetivo del presente estudio fue evaluar las modificaciones psicofisiológicas indicadores de fatiga mental en 24 Controladores de Tránsito Aéreo expuestos a la pantalla de radar. Las pruebas que se utilizaron para evaluar la fatiga fueron: Variabilidad de la Frecuencia Cardíaca, Destreza Manual y Precisión, Patrones Subjetivos de Fatiga de Yoshitake, Frecuencia Cardíaca y Tensión Arterial. Estas pruebas se aplicaron en todos los sujetos tanto expuestos como no expuestos a la pantalla de radar en dos momentos, y en tres sesiones durante la jornada laboral. Adicionalmente se evaluó el estado general de salud de los trabajadores, las características del ambiente de trabajo, la actividad del proceso laboral y el puesto de trabajo. En el análisis de los datos se observó un mayor porcentaje de fatiga en los Controladores Aéreos Expuestos según la prueba de Patrones Subjetivos de Fatiga. Con respecto a la Variabilidad de la Frecuencia Cardíaca, el 50 por ciento de los Controladores de Tránsito Aéreo se encontraron fatigados al inicio y a lo largo de la jornada. El 50 por ciento de los Controladores de Tránsito Aéreo presentaron una disminución en la prueba de Destreza Manual y Precisión en las tres sesiones y finalmente el análisis de la Tensión Arterial reportó un mayor porcentaje al Controladores de Tránsito Aéreo con cifras tensionales elevadas luego de dos horas de exposición. En el análisis inferencial no se encontraron diferencias estadísticas significativa entre los dos momentos ni entre las sesiones evaluadas