目標：臺灣缺乏深度分析民眾運動習慣之文獻，本研究以相同分析方法比較臺灣與美國的運動習慣。 方法：利用臺灣國民健康訪視調查 (NHIS 2001) 及美國國民健康與營養調查(NHANES 1999-2002)，將運動時間、強度與頻率轉換為個人熱量消耗(MET)作分析比較。 結果：臺灣民眾有半數自認不運動，是美國人的2.5倍。以每週達1,000 kcal之運動熱量為標準，美國是臺灣的2.5倍。青壯年族群 (25-44歲) 美國 達到標準的有34.3%，是臺灣的3-7倍。高教育美國人達標準的有40.2%，是臺灣的2.5倍。運動盛行率在美國年輕人最高，隨年齡增加而遞減， 但在臺灣則呈現『U』字形現象，在老年(≥65歲)達最高峰。有運動 (每週≥1,000 kcal) 的美國人每天運動40分鐘，每週消耗1,083 kcal (每天155 kcal) (中位數)，而臺灣人只有20分鐘，每週消耗544 kcal (每天78 kcal)，女生比男生又少1/3。 結論：臺灣民眾普遍不運動，一半人自稱沒有運動，運動習慣不到美國的一半，6/7人口運動不足。最嚴重問題出現在青壯年、高教育、高收入族群，而且即使有運動的少數，他們運動強度及熱量消耗也明顯偏低不足。建議有關單位以鼓勵民眾運動為當前急務，以每週運動熱量至少達750 kcal為全民運動新目標，以「日行萬步」來互勉，將可大幅提昇健康，也可減少健保可觀的支出。

Objectives: In assessing the adequacy of leisure time physical activity (LTPA) in Taiwan, a cross-country comparison is an important approach. Using the same methodology, the prevalence of LTPA was compared between Taiwan and the U.S. Methods: The metabolic equivalent (MET), a unit of exercise intensity, or calories was assigned to each LTPA reported in the NHIS 2001 (Taiwan) and the NHANES 1999-2002 (U.S.), each consisting of nationally representative samples of the respective country. Results: More than one-half of the population in Taiwan (50.2%) reported no LTPA, 2.5 times more than in the U.S. (21.3%). The proportion reaching 1,000 kcal/week in the U.S. (31.7%) was 2.5 times that in Taiwan (13.9%), but among the young adult group (25-44 yrs of age), Americans (34.3%) had 4 times more LPTA reaching 1,000 kcal/week than Taiwanese (8.5%). Among the highest educated, Americans (40.2%) were 2.5 times more likely to reach the desired LPTA goal (i.e., 1000 kcal/week) than Taiwanese (16.6%). The prevalence of LTPA decreased with age in the U.S., but in Taiwan the prevalence peaked with the elders (65 yrs of age or older), with the prevalence curve showing a unique “U” shape. Even among the physically active, the median daily LTPA energy expenditure for Americans was 155 kcal/day with 40 minutes of exercise per day, twice that of Taiwanese who expended 78 kcal/day and exercised 20 minutes/day. Conclusions: Taiwanese are deficient in LTPA in two ways: 1) few people exercise and 2) among the few who do exercise, energy expenditure is inadequate. Six out of seven adults in Taiwan fail to meet the minimal level of exercise recommended. The proportion who exercise in Taiwan was less than one-half that of Americans, but the most serious deficiency was found among the young adults (25-44 years of age), who are potentially productive, and the college-educated or the higher income group, who are potential role models. If the inactive Taiwanese could be encouraged to become more active through physician counseling, the health benefits would be substantial and significant savings would be realized in the medical expenditure by the National Health Insurance.