部分睡眠剝奪後攝取咖啡因對認知及10公里跑步表現之影響

Abstract

背景：部分睡眠剝奪（partial sleep deprivation, PSD）會對耐力運動表現及認知功能產生負面影響。先前研究顯示單次咖啡因增補可以提升立即性耐力運動表現及認知功能，且認知功能在立即性耐力運動後可以獲得改善。但對於部分睡眠剝奪後增補咖啡因對耐力運動表現，及在立即性耐力運動後的認知功能是否有加乘之效益仍不清楚。目的：探討部分睡眠剝奪後，增補咖啡因對立即性耐力運動表現之影響及在立即性耐力運動後認知功能是否有加乘之效益。方法：招募10名有跑步習慣的男性，以雙盲、重複量數、平衡次序的設計，進行部分睡眠剝奪（3：00至6：00）搭配咖啡因增補（每公斤體重6毫克）及安慰劑兩種實驗處理，隨後並進行一次跑步機10公里計時測驗，且在增補前、增補後和運動後測量史翠普作業（stroop test）。另外，實驗過程亦收集呼吸、心跳、運動自覺努力程度之數據。統計方法以重複量數ANOVA比較增補因子、時間因子對認知功能之差異；相依樣本t檢定比較增補因子對10公里計時測驗表現之差異。結果：咖啡因增補處理之10公里計時測驗成績顯著優於安慰劑處理（47.85 ± 7.29分鐘 vs. 51.39 ± 8.42分鐘）（p< .05）。反應正確率部分，不論是一致情境或不一致情境在增補處理間及時間點之間皆無顯著差異（p > .05）；反應時間部分，不論是一致情境或不一致情境在增補處理間皆無顯著差異，但增補前顯著大於增補後，且增補後大於運動後（p < .05）。結論：在部分睡眠剝奪的狀況下，增補每公斤體重6毫克的咖啡因，可以提升耐力運動表現，但並未有助於改善認知功能。Background: Partial sleep deprivation (PSD) impairs endurance exercise performane and coginitive function. Previous studies have shown that caffeine (CAF) supplement can elevated acute endurance exercise performance and coginitive function, and that cognitive function can be improved after acute endurance exercise. However, it’s unclear whether CAF supplementation after PSD has an effect on the performance of acute endurance exercise and whether there is a synergistic effect on cognitive function after acute endurance exercise. Purpose: It aimed to investigate the effects of CAF supplementation on performance of acute endurance exercise after PSD and whether there is a synergistic effect on cognitive function after acute endurance exercise. Method: 10 young physically active men were recruited and double-blinded, repeat the measurement and crossover design. PSD (3:00-6:00) was treated with each trial, CAF (6mg/kg) supplementation or placebo (PLA), followed by a treadmill 10-km time-trial (TT）and cognitive function tests were measured pre-supplementation, post-supplementation, and post-exercise. In addition, data on V̇O2 max, HR, and RPE were also collected during the experiment. A repeated measures ANOVA with two within factors (time and supplemenetary) was used to determine different the coginitive function；The t test compares the performance of the supplementary factor on the treadmill 10 km TT after PSD. Results: There was a significant difference in CAF supplementation or PLA of the 10km TT (47.85 ± 7.29 min vs. 51.39 ± 8.42 min) (p< .05). There was no sigficant difference in CAF supplementation or PLA between the trials of the correct response rate, whether in a consistent or inconsistent situation (p > .05）；Response time (RT), no matter consistent or inconsistent, there was no significant difference, but pre-supplementation was significantly greater than post-supplementation, and post-supplementation was greater than post-exercise (p < .05). Conclusion: Supplementing CAF (6mg/kg) can increased endurance exercise performance in conditions of PSD, but did not improved cognitive function.