podendo assim levar a uma menor solicitacao mecanica dessa articulacao. O torque no quadril tambem aumentou durante a condicao em que o joelho ultrapassa o tornozelo, o que, de forma analoga, pode levar a uma maior sobrecarga lombar nesta condicao.Dessa forma, sendo a forca patelofemoral maior na condicao em que o joelho ultrapassa o tornozelo e que, nessa condicao, parece ocorrer um maior torque na articulacao do quadril, realizar o agachamento livre, com barra passando o joelho da linha do pe, nao parece ser o modo mais seguro de execucao desse movimento. Por outro lado, passar o joelho, ao executar o agachamento, poderia ser justificado pelo aumento da solicitacao da musculatura do quadriceps durante a execucao desse movimento. Porem, para esse fim, e recomendavel entao aumentar a carga levantada em vez de passar o joelho da linha do pe.REFERENCIAS BIBLIOGRAFICAS1. Abelbeck KG. Biomechanical model and evaluation of a linear motion squat type exercise. J Strength Cond Res. 2002;16: 516-24. [ Links ]2. Escamilla RF. Knee biomechanics of the dynamic squat exercise. Med Sci Sports Exerc. 2001;33:127-41. [ Links ]3. Escamilla RF, Fleisig GS, Lowry TM, Barrentine SW, Andrews JR. A three-dimensional biomechanical analysis of the squat during varying stance widths. Med Sci Sports Exerc. 2001; 33:984-98. [ Links ]4. Escamilla RF, Fleisig GS, Zheng N, Barrentine SW, Wilk KE, Andrews JR. Biomechanics of the knee during closed kinetic chain and open kinetic chain exercises. Med Sci Sports Exerc. 1998;30:556-69. [ Links ]5. Escamilla RF, Fleisig GS, Zheng N, Lander JE, Barrentine SW, Andrews JR, et al. Effects of technique variations on knee biomechanics during the squat and leg press. Med Sci Sports Exerc. 2001;33:1552-66. [ Links ]6. Fry AC, Smith JC, Schilling BK. Effect of knee position on hip and knee torques during the barbell squat. J Strength Cond Res. 2003;17:629-33. [ Links ]7. Reilly DT, Martens M. Experimental analysis of the quadriceps muscle force and patello-femoral joint reaction force for various activities. Acta Orthop Scand. 1972;43:126-37. [ Links ]8. Wretenberg P, Feng Y, Arborelius UP. High- and low-bar squatting techniques during weight-training. Med Sci Sports Exerc. 1996;28:218-24. [ Links ]9. Cohen ZA, Roglic H, Grelsamer RP, Henry JH, Levine WN, Mow VC, et al. Patellofemoral stresses during open and closed kinetic chain exercises. An analysis using computer simulation. Am J Sports Med. 2001;29:480-7. [ Links ]10. Cappozzo A, Catani F, Croce UD, Leardini A. Position and orientation in space of bones during movement: anatomical frame definition and determination. Clin Biomech (Bristol, Avon). 1995;10:171-8. [ Links ]11. Piazza SJ, Okita N, Cavanagh PR. Accuracy of the functional method of hip joint center location: effects of limited motion and varied implementation. J Biomech. 2001;34:967-73. [ Links ]12. Bell AL, Pedersen DR, Brand RA. A comparison of the accuracy of several hip center location prediction methods. J Biomech. 1990;23:617-21. [ Links ]13. Leva P. Adjustments to Zatsiorsky-Seluyanov's segment inertia parameters. J Biomech. 1996;29:1223-30. [ Links ]14. Zatsiorsky MV, Seluyanov VN, Chugunova L. In vivo body segment inertial parameters determination using a gamma-scanner method. In: Berme N, Cappozzo A, editores. Biomechanics of human movement: Aplications