目的：發展一套身體活動行為改變策略和雲端活動促進系統，探討其對臺灣女高中生中等費力身體活動時間的影響。方法：以臺灣某女子高中一年級三個班共98位學生為研究對象，進行為期13週的準實驗設計，其中實驗介入為第2至13週共12週。自變項為行為改變策略暨雲端活動促進系統，分三個組別：一般高中體育課程 (對照組)；運用雲端活動促進系統 (實驗組一)；接受行為改變策略暨雲端活動促進系統 (實驗組二)。其中實驗組二的行為改變策略內容為第2至8週接受跨理論模式和目標設定，第9 至10週為社群活動熱身賽，第11至12週為社群活動衝刺賽，最後第13週為課程回顧。以單因子變異數分析檢驗三個班級中等費力身體活動時間的差異情形。結果：第2至4週的中等費力身體活動時間以實驗組一顯著多於對照組，而第9至10週則是實驗組二多於對照組。結論：運用雲端活動促進系統還需結合身體活動行為改變策略，最能有效提升和維持學生身體活動動機和行為。

Purpose: The aim of this study was to investigate the effectiveness of behavioral change strategies and ubiquitous Cloud-based Health Assessment, Management, and Promotion system (uCHAMPsys) on moderate physical activity time (MPAT) of high school female students. Methods: There were ninety-eight 10th grade students from three classes involved in the study by employing a 13-week quasi-experimental design with the use of pre- and post-test. The independent variable was the intervention on three different levels: general high school physical education (control group); application of uCHAMPsys (experimental group I); implication of behavioral change strategies and application of uCHAMPsys (experimental group II). The dependent variable was the MPAT that students allocated every week. One-way ANOVA was employed to examine whether there was a difference between the three research groups. Results: Our findings indicate that the students of the experimental group I showed the MPAT significantly higher than the control group from weeks 2 to 4, and the students of the experimental group II showed the MPAT significantly higher than the control group participants from weeks 9 to 10. Although there was no significant difference in the MPAT between the three research groups from the rest of periods, the students from the experimental group II maintained moderate amounts of activity than the other two groups. Conclusions: It is suggested that behavioral change strategies can be integrated into uCHAMPsys, which can enhance and maintain students’ motivation in physical activity and behavioral change most effectively.