近年來，由於生活品質提高，使得休閒運動的風潮盛行，利用伏地挺身與仰臥推舉運動來鍛鍊身體是很常見的。回顧前人文獻，發現在運動過程中，對於上肢關節的受力及力矩的研究上，已做過詳細地探討。此外，對於上肢肌肉活化的情形也是個重要的結果，故本實驗的目的就是接續分析不同動力鏈運動，對上肢各關節負荷之優缺點及肌肉活化程度的影響。

受限於實驗的危險性及活動時人體測量上肢關節的困難，目前仍缺乏有關上肢不同動力鏈運動之優缺點討論。為了預防及幫助臨床上的治療與復健，藉由伏地挺身與仰臥推舉運動的訓練模式，可以進一步探討上肢各關節運動的機制及如何來預防傷害。

利用3D動態分析系統、測力板及表面肌電訊號感測器，來模擬上肢各關節在不同動力鏈運動時所承受的負載情形，以及量測上肢肌肉的表面肌電訊號，希望瞭解不同動力鏈運動對於上肢肌肉的訓練成效和提供各關節在動態負載下預防受傷的機制。

針對15位上肢無傷殘病史、受過重量訓練且慣用手皆為右手之年輕男性，在相同的速度及初始負荷值的條件下，進行伏地挺身與仰臥推舉運動的實驗，計算出腕、肘及肩關節在做伏地挺身與仰臥推舉運動時的受力與力矩，並同步量測胸大肌、三頭肌、肱二頭肌、脊上肌以及前、中、後側三角肌的活化情形。

實驗結果發現，在關節受力的部分，腕、肘及肩關節受力方向皆呈現伏地挺身運動所產生的受力較大；在關節力矩的部分，腕、肘及肩關節力矩方向皆呈現伏地挺身運動所產生的力矩較大，且兩運動的變化趨勢皆一致，而三個關節力矩方向皆以屈曲、伸展力矩為最大；在各肌肉活化的部分，發現在上身過程中，肌肉是較活化的狀態，以總活化值來比較下，對於胸大肌、三頭肌、肱二頭肌及前、中側三角肌有加強訓練的效果，尤其是以仰臥推舉運動做訓練，對肌肉的訓練效果更明顯。

整體而言，不論是受力或力矩方面，皆顯示仰臥推舉運動所產生的力及力矩較小；另外在肌力上的訓練，相對於伏地挺身運動，肌肉也有明顯的活化效果。故一般人若想要強化上肢肌力的運動，建議以開放動力鏈運動較佳。

Objective. In recent years, there has been growing of outdoor activity due to the increase of the life quality. Pushup (PU) and Bench Press (BP) exercises have been used for the training of the upper extremities. Reviewing of the literature, finding the force and moment of the upper extremity has been discussed during exercises in detail. Besides, muscle activation is also an important result, so the purpose of this study was to analyze different kinetic chain exercises the effects of the upper extremity loading and muscle activation.

Background. Limited by the measuring difficulty of upper extremity and the experiment is dangerous, there is very little relating to the comparison among different kinetic chain exercises of the upper extremity. In order to prevent and help clinical therapy and rehabilitation, training of PU and BP exercises were used to further explore the effects of the upper extremity mechanism and how to prevent the injury.

Methods. The use of three-dimensional motion analysis system (Motion Analysis Corp., Santa Rosa, C.A., U.S.A.), force plate (Type 9281B, Kistler Instrument AG CH-8408 Winterthur, Switzerland), and surface EMG (MA300, Motion Analysis Crop., U.S.A.), has imitated the upper extremity loading and measured surface of EMG muscle activation during different kinetic chain exercises. We hope to understand the effects of muscle training and mechanism of offering prevent injure of the upper extremity.

Design. Fifteen young men who non-injured, trained, and dominant is right hand volunteered for this study, with an average age of 19.8 years, an average tall of 176.8cm, average weight of 69.27kg. To carry on the experiment of PU and BP exercises under condition of the same speed and loading value. Both force and moment of the wrist, elbow, and shoulder joint was calculated and muscle activation of pectoralis major, triceps-long head, biceps brachii, supraspinatus, deltoid anterior, deltoid middle, and deltoid posterior the was measured during PU and BP exercises.

Results. The results show in joint force part that every joints loading is bigger during PU exercise. As for the joint moment part, every joints moment is bigger during PU exercise. Flexion/Extension moment is biggest among every joints moment and the curve is synchronous between PU and BP exercises. Moreover, in the muscle activation part, doing exercises can bring muscle activation during down to up state. Effects are obvious show that pectoralis major, triceps-long head, biceps brachii, deltoid anterior, and deltoid middle on value of muscle activation.

Conclusion. Overall, during PU exercise, joint loading to the upper extremity is greater than joint loading during the BP exercise. Furthermore, there is more muscle activation during the BP exercise. Therefore, open chain exercise with BP exercise is an effective way to strengthen the upper extremity. So people want to exercise that strengthen muscle of the upper extremity suggest open kinetic chain is better.

1.Tibbitts, G.M., “Patients who fall: How to predict and prevent injuries,” Geriatrics, Vol.51, No.9, pp.24-31, 1996.

2.Manning, D.P., Ayers, I., Jones, C., Bruce, M., and Cohen, K., “The incidence of underfoot accidents during 1985 in a working population of 10,000 Merseyside people,” Journal of Occupational Accidents, Vol.10, No.2, pp.121-130, 1988.

3.Adesunkanmi, A.R., Oginni, L.M., Oyelami, A.O., and Badru, O.S., “Epidemiology of childhood injury,”
Journal of Trauma, Vol.44, No.3, pp.506-512, 1998.
4.An, K.N., Korinek, S.L., Kilpela, T., and Edis, S., “Kinematic and kinetic analysis of push-up exercise,” Biomedical Sciences Instrumentation, Vol.26, pp.53-57, 1990.

5.An, K.N., Browne, A.O., Korinek, S., Tanaka, S., and Morrey, B.F., “Three-Dimensional Kinematics of Glenohumeral Elevation,” Journal of Orthopeadic Research, Vol.9, No.1, pp.143-149, 1991.

6.Snyder-Macker, L., Delitto, A., Baliey, S.L., and Stralka, S.W., “Strength of the quadriceps femoris muscle and functional recovery after reconstruction of the anterior cruciate ligament. A prospective, randomized clinical trial of electrical stimulation,” Journal of Bone and Joint Surgery, Vol.77, No.8, pp.1166-1173, 1995.

7.Blackard, D.O., Jensen, R.L., and Ebben, W.P., “Use of EMG analysis in challenging kinetic chain terminology,” Med Sci Sports Exerc, Vol.31, No.3, pp.443-448, 1999.

8.Chou, P.H., Chou, Y.L., Lin, C.J., Su, F.C., Lou, S.Z., Lin, C.F., and Huang, G.F., “Effect of elbow flexion on upper extremity impact forces during a fall,” Clinical Biomechanics, Vol.16, No.10, pp.888-894, 2001.

9.Lou, S.Z., Lin, C.J., Chou, P.H., Chou, Y.L., and Su, F.C., “Elbow load during push-up at various forearm rotations,” Clinical Biomechanics, Vol.16, No.5, pp.408-414, 2001.

10.Chou, P.H., Lin, C.J., Chou, Y.L., Lou, S.Z., Su, F.C., and Huang G.F., “Elbow Load with Various Forearm Position during One-handed Push-up Exercise,” International Journal of Sports Medicine, Vol.23, No.6, pp.457-462, 2002.

11.Chou, P.H., Chou, Y.L., Ho, C.S., Jiang, S.S., and Wei, H.C., “Biomechanical Analysis of Wrist Loading during Lifting Tasks,” Chinese journal of Mechanics, Vol.17, No.4, pp.349-357, 2001.

12.Chou, P.H., Chen, S.K., Chou, Y.L., Su, F.C., Shi, Y.C., Huang, G.F., and Wu, T.C., “Biomechanical analysis for the effect of elbow initial flexion angles on upper extremity during a fall,” Biomedical Engineering Application Basic Communications, Vol.14, No.1, pp.40-46, 2002.

13.Lou, S.Z., Chou, P.H., Su, F.C., Lin, C.J., and Chou, Y.L., “Change of Elbow Joint Load from Two-handed to One-handed Push-up Exercise,” Journal of Medical and Biological Engineering, Vol.22, No.1, pp.19-24, 2002.

14.Chou, P.H., Chou, Y.L., Kuo, C.M., Chen, S.K., and Huang, G.F., “Analysis for Different Push-Up Speed on Joint Loading of the Upper Extremity,” Annual Report, National Science Council NSC91-2320-B- 037-017, 2002.

15.Uhl, T.L., Carver, T.J., Mattacola, C.G., Mair, S.D., and Nitz, A.J., “Shoulder Musculature Activation During Upper Extremity Weight- Bearing Exercise,” Journal of Orthopedic Sport Physical Therapy, Vol.33, No.3, pp.109-117, 2003.

16.Chou, P.H., Chou, Y.L., Syu, J.A., Chen, S.K., and Huang, G.F., “Biomechanical Analysis of Upper Extremity during Different Open Kinetic Chain Exercise,” Annual Report, National Science Council NSC93-2213- E-037-002, 2005.

17.Chou, P.H., Chou, Y.L., Chien, P.E., Chen, S.K., and Huang, G.F., “Comparative Analysis between Open Kinetic Chain and Closed Kinetic Chain Exercise of the Upper Extremity,” Annual Report, National Science Council NSC94-2213-E-037-005, 2006.

18.Dempster, W.T., Space requirements of the seated operator. Geometrical, kinematic and mechanical aspects of the body with special reference to the limbs. US Wright Air Development Center. Tech. Report. 55-159, 1955.

19.Perotto, A., Delagi, E.F., Iazzetti, J., and Morrison, D., Anatomic Guide for the Electromyographer: The Limbs, 2nd ed, Charles C Tomas, Springfield, Illinois, U.S.A., pp.65-95, 1980.

20.Woltring, H.J., “A FORTRAN package for generalized, cross-validatory spline smoothing and differentiation,” Advanced Engineering Software, Vol.8, No.2, pp.104-113, 1986.