研究：運動前喝杯咖啡可以加速脂肪燃燒

陽春四月不減肥，春暖花開肉一堆。想甩掉陳年老肥，當然要運動起來！研究發現，如果在運動之前喝上一杯咖啡，就可以加速脂肪燃燒。這是真的嗎？

If you're looking to maximize the amount of fat burned in your next workout, think about having a coffee half an hour before you get started – as a new study suggests it can make a significant difference to fat burning, especially later on in the day.

如果你希望下一次鍛鍊時最大化地提高脂肪燃燒量，不妨考慮在運動前半小時喝杯咖啡——因爲有新研究表明，它可以使脂肪燃燒量明顯變化，尤其是在下午。

Researchers found that 3 milligrams of caffeine per kilogram of body weight can boost the rate of fat burning during aerobic exercise, based on results gathered from 15 male volunteers.

研究人員收集了15名男性志願者的數據後發現，如果按每公斤體重3毫克的量來攝入咖啡因，就可以提高有氧運動中的脂肪燃燒速度。

The coffee dose was shown to increase maximal fat oxidation rate (a measure of how efficiently the body burns off fat) by an average of 10.7 percent in the morning and 29 percent in the afternoon.

研究表明，咖啡可以增加最大脂肪氧化率，上午平均增加10.7%，下午增加29%。最大脂肪氧化率用於衡量身體有效燃燒脂肪的效率。

"The recommendation to exercise on an empty stomach in the morning to increase fat oxidation is commonplace," says physiologist Francisco José Amaro-Gahete from the University of Granada in Spain. "However, this recommendation may be lacking a scientific basis, as it is unknown whether this increase is due to exercising in the morning or due to going without food for a longer period of time."

“早上空腹運動以增加脂肪氧化的說法很常見，”西班牙格拉納達大學的生理學家弗朗西斯科·何塞·阿馬羅-加赫特說，“然而，這一建議可能缺乏科學依據，因爲不知道脂肪燃燒量增加是由於早上運動還是由於長時間不進食。”

The researchers were also keen to look in closer detail at the relationship between caffeine and exercise. The stimulant is often associated with improved athletic performance, though the science behind this link isn't as comprehensive as it could be.

研究人員也很想更細緻地考察咖啡因與運動之間的關係。咖啡因經常和運動表現改善相關聯，儘管這種聯繫背後的科學根據並不多。

Across the course of four weeks, the 15 volunteers in the study went through four tests in a random order: taking a placebo at 8 am, taking a placebo at 5 pm, taking a caffeine supplement at 8 am, and taking a caffeine supplement at 5 pm.

在四周的時間裏，參與研究的15名志願者以隨機順序進行了4組測試：早上8點服用安慰劑；下午5點服用安慰劑；早上8點服用咖啡因補充劑；下午5點服用咖啡因補充劑。

In subsequent cycling tests after the stimulant or placebo had been given, the fat-burning capability of the body was measured, showing the impact that caffeine had made on MFO. Maximum oxygen uptake was also boosted, as was the intensity of exercise.

在服用咖啡因補充劑或安慰劑後的騎車測試中，研究人員測量了志願者身體的脂肪燃燒能力，揭示出咖啡因對最大脂肪氧化率的影響。研究人員發現，志願者的最大攝氧量也得到了提升，運動強度也加大了。

"The results of our study showed that acute caffeine ingestion 30 minutes before performing an aerobic exercise test increased maximum fat oxidation during exercise regardless of the time of day," says Amaro-Gahete.

阿馬羅-加赫特說：“我們的研究結果表明，在進行有氧運動測試前30分鐘快速攝入咖啡因，無論在一天當中的什麼時候，都能增加運動過程中的最大脂肪氧化量。”

This is a study with a fairly small sample of participants, so it's important not to jump to too broad a conclusion, but the results are clear enough to suggest that there is some kind of association there.

由於該研究樣本量過小，所以還不清楚結論是否具有普遍性，但可以明確的是，咖啡因和脂肪燃燒之間存在某種關聯。

"Overall, these results suggest that a combination of acute caffeine intake and exercise at moderate intensity in the afternoon provides the best scenario for individuals seeking to increase whole-body fat oxidation during aerobic exercise," the researchers conclude.

研究人員總結道：“總體來說，這些結果表明，急性咖啡因攝入和下午中等強度的運動相結合，爲那些希望在有氧運動中加速全身脂肪燃燒的人提供了最佳方案。”

The research has been published in the Journal of the International Society of Sports Nutrition.

這項研究被髮表在《國際運動營養學會雜誌》上。