肌力是臨床上評估運動功能障礙病人進步程度的重要指標。目前臨床上因為手握式肌力測試儀可提供比傳統徒手測試精準且定量的肌力資訊，加以其輕巧、方便攜帶及容易使用，所以常用來評估病人的肌力。但是，過去研究顯示手握式肌力測試儀測試信度偏低，測試人員肌力不足是主因。若測試者肌力小於受測者之肌力便會造成量測誤差。為降低肌力量測的誤差，本研究旨在發展一個兼具手握式肌力測試儀優點且不因測試人員肌力大小不同而影響測試結果的肌力量測工具，並測試其信度及效度。 本研究第一部份係以研發新式肌力測試儀為主，第二部份則是利用Kin-Com作為黃金標準檢測新式肌力測試儀及傳統手握式肌力測試儀之量測效度，並測試三種儀器單一測試內信度及新式肌力測試儀同日與不同日之測試信度。新式肌力測試儀係利用槓桿原理，藉由增長施力臂使施測者以較小之力量即可達到臨界使力狀態下的肌力大小，克服施測者肌力不足的問題，故稱之為槓桿式省力肌力測試儀（Lever-Based Effort Saving Dynamometer（LESD））。槓桿式省力肌力測試儀更結合電腦輔助系統，可紀錄肌力變化的過程並決定最大肌力，減少人為誤差。在檢測儀器效度方面，共有25名健康年輕男性參與，在測試槓桿式省力肌力測試儀同日及不同日量測信度方面則由13名女性及14名男性全程參與實驗。實驗結果顯示雖然施測者肌力大小不同，但是利用槓桿式省力肌力測試儀量測所得股四頭肌及大腿後肌二個肌群之肌力值並無顯著差異（P>0.05，ICC>0.95）。相對地，使用手握式肌力測試儀量測股四頭肌，則有顯著差異。與Kin-Com比較，槓桿式省力肌力測試儀量測的肌力數值並無顯著差異(r>0.89)，而手握式肌力測試儀量測二個肌群的肌力數值則有顯著差異。（股四頭肌：平均差異百分比>52.66％；大腿後肌：平均差異百分比>27.22％）。在同日測試中三種儀器均顯示高度測試內信度。槓桿式省力肌力測試儀在不同日重複測試有極高的信度（ICC>0.91）。 實驗證實本研究研發的槓桿式省力肌力測試儀不論是信度或效度均較手握式肌力測試儀為佳。其重量、造價、所需空間及測試時間又較Kin-Com等動態肌力測試儀更為經濟，故建議可在臨床肌力量測上廣泛應用。而本研究選取之男女施測者均是各該性別之典型臨床人員，其肌力亦具代表性。又實驗族群為正常年輕人，其肌力一般而言較其他族群為大。因此，實驗所得結果更彰顯了槓桿式省力肌力測試儀比傳統量測法優異之處。未來除針對不同的受試族群及肌群進行研究，以進一步確認槓桿式省力肌力測試儀的優異性外，利用槓桿式省力肌力測試儀研究使力測試及臨界使力測試二種肌力評估方式的精確性與穩定性，相信有助於臨床人員選擇較佳的肌力評估方式。; Muscle strength is an important indicator for the progress of rehabilitation of patients with movement disability. In clinical practice, hand-held dynamometers have become more widely used for the assessment of muscle strength than traditional manual muscle testing as they provide quantitative measures of muscle strength and are portable, accurate and easy to use. However, the strength of examiners has been suggested to influence the reliability of hand-held dynamometers especially when applied to muscles of high strength. A more accurate and reliable measurement device is needed for the quantification of the strength of muscle with high strength, such as lower extremity muscles. The purposes of this study were: (1) to develop a new muscle strength measurement system whose measurements are not affected by the examiner''s muscle strength, (2) to assess the validity and intra-rater, inter-rater, and inter-session reliability of the new device in testing lower extremity muscles and (3) to assess the reliability of different examiners in testing lower extremity muscle strength with the new device. The new device using the effort-saving system reduces the influence of examiner''s muscle strength when measuring the subject muscle strength. The effort-saving system is based on leverage, which increase lever arm to enhance examiner''s muscle strength. Therefore the new device is named Lever-Based Effort Saving Dynamometer（LESD）. For establishing the validity and intra-rater, inter-rater reliability of LESD in testing quadriceps and hamstrings muscle strength, 25 healthy young men and two examiners participated in this study. Twenty-seven healthy volunteers were also recruited for within-day and between-day inter-session reliability study. The results of the present study showed that even though the examiners had different muscle strength, with LESD there was no significant difference between the values of the quadriceps and hamstrings strength measured by different examiners (ICC>0.95). On the contrary, significant difference in the measured quadriceps strength was found between the examiners with the hand-held dynamometer. There was no significant difference between the muscle strengths measured by KIN-COM and LESD (r>0.89) but significant differences existed in the measurements by the hand-held dynamometer and the KIN-COM (quadriceps: mean difference percentage > 52.66%; hamstrings: mean difference percentage > 27.22%). High within-day reliability was found for all the three devices. Lever-Based Effort Saving Dynamometer (LESD) had very high between-day reliability (ICC>0.91). The results of the present study showed that the validity and reliability of the new device were much higher than traditional hand-held dynamometers. It is lighter and less expensive
