This study investigated the effects of high-carbohydrate (HC) and high-fat (HF) diet on cognitive performance, and subjective and objective sleepiness. Seven male participants were kept awake for 24 h in a metabolic ward. Meals were given every 4h and cognitive performance and sleepiness ratings were assessed hourly. The Karolinska Drowsiness Test (KDT, EEG derived) was performed twice after meal. Performance in simple reaction time showed a significant interaction of diet and the post-prandial period, a slower reaction time was observed for the HC-diet 3.5 h after meal intake. Diet did not affect EEG measures but a general post-prandial increase of objective sleepiness was observed 3.5h after meal servings. The HC-diet was significantly associated with an increase of subjective sleepiness. The study demonstrated that the HC-diet caused larger oscillation in performance and increased sleepiness as compared to HF-diet throughout day and night.

中文翻译：

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在恒定条件下 24 小时唤醒期间的表现和困倦受饮食影响

本研究调查了高碳水化合物 (HC) 和高脂肪 (HF) 饮食对认知能力以及主观和客观嗜睡的影响。七名男性参与者在代谢病房中保持清醒 24 小时。每 4 小时进餐一次，每小时评估一次认知能力和困倦程度。Karolinska 嗜睡测试（KDT，EEG 衍生）在餐后进行两次。简单反应时间的表现表明饮食和餐后时期有显着的相互作用，在进餐后 3.5 小时观察到 HC 饮食的反应时间较慢。饮食不影响 EEG 测量，但在餐后 3.5 小时观察到客观嗜睡的总体餐后增加。HC 饮食与主观嗜睡的增加显着相关。