本研究旨在探討持住時間與作業高度對於男性頭上作業之最大可承受持住能力之影響。共徵募15位男性受試者，以心物法來收集和檢定在不同之作業高度（頭頂高、過頭手及和最大過頭手及）與持住時間（30秒、1分鐘、2分鐘和3分鐘）對於頭頂作業（天花板）之最大可承受持住重量(Maximum Acceptable Weights of Holding, MAWH)、心搏率(Heart Rate, HR)以及主觀知覺施力評量(Rating of Perceived Exertion, RPE)之效應。結果發現作業高度與持住時間對於MAWH均具有顯著效應。此外，在作業高度對於平均心博率有顯著的效應，但持住時間則無顯著的效應。作業高度對於RPE並無顯著效應，持住時間對於RPE則具有非常顯著的效應，並以手臂最累。整體而言，在作業高度方面最大過頭手及之MAWH顯著大於過頭手及頭頂高，而過頭手及和頭頂高兩者之間的MAWH則無顯著差異。因3分鐘的RPE顯著大於30秒，1分和2分，而其他三者並無顯著差異。在持住時間方面，以30秒之MAWH為最大，其次為1分、2分，而以3分為最低且四者之間具有顯著差異。因3分鐘的RPE顯著大於30秒、1分、2分，而其他三者並無顯著差異。本研究建議頭上之持住作業應盡量降低每次的作業時間，並盡量減少手臂的施力。

This study investigate the effect of holding time and working height on maximum acceptableholding capacity in overhead work. Fifteen males participated in the experiment. The psychophysicalapproach was used to examine the effects of different working heights (overhead , overhead reachand maximum reach height) and different holding times (30s, 1, 2and 3 minutes) on the maximumacceptable weight of holding (MAWH), heart rate (HR) and rating of perceived exertion (RPE).Participants simulated overhead work to hold a box vertical against ceiling. The results indicate thatthe working height and holding time have a signifi cant infl uence on MAWH. However, the heart rateis not signifi cantly infl uenced by the working height and working time. The overall RPE values aresignifi cantly infl uenced by the holding time. The most stresses body parts are the arms. The MAWH ofthe maximum reach height is signifi cantly larger than that for the overhead reach and the overhead, andthat the MAWH for the overhead reach and the overhead is not signifi cantly different. In general, thesefi ndings indicate that the holding task of overhead should be performed by maximum reach height withshorter holding times.