Abstract
The validation of a new dynamometer for evaluation of dynamic muscle work is presented. The device was based on a precise measurement of load displacements of any machine using gravitational loads as external resistance. It allowed, through a sensor consisting of an infrared photo interrupter, the calculation of velocity, force and power during concentric, eccentric and stretch-shortening cycle activity. To validate the dynamometer 33 male and female track and field athletes (12 throwers and 21 jumpers) participated in the study. The throwers (4 women and 8 men) were asked to perform half-squat exercises on a slide machine with a load of 100% of the subject's body mass. The day-to-day reproducibility of half-squat exercises gave a correlation coefficient ofr = 0.88, 0.97 and 0.95 for average push-off force (AF), average push-off velocity (AV), and average push-off power (AP) respectively. Comparison of half-squat measurements was performed against jumping and running test evaluation by the jumpers (7 women and 14 men). The interrelationships among the different variables studied demonstrated a strong correlation between AF, AV and AP and sprinting and jumping parameters (r = 0.53−0.97;P < 0.05−0.001). Using values of AF, AV and AP developed in half-squat exercises executed with different loads, ranging from 35% to 210% of the subject's body mass, it was also possible to establish the force-velocity and power-velocity relationships for both male and female jumpers. In any individual case, the maximal error due to the measurement system was calculated to be less than 0.3%, 0.9% and 1.2% for AF, AV, and AP respectively. Given the accuracy of the ergometer, the high reliability found between 2 days of measurements, and the specificity of the results it is suggested that the dynamic dynamometer would be suitable for evaluation of athletes performing specific skills. In addition, because single and multiple joint movements involving appropriate muscle groups can be easily performed, physiological characteristics could be evaluated for both athletic and rehabilitation purposes. Therefore, because of its simplicity of use and application, and its low cost the dynamometer would be suitable for both laboratory and field conditions.
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References
Anderson M, Cote R, Coyle E, Roby F (1979) Leg power, muscle strength, and peak EMG activity in physically active college men and women. Med Sci Sports 11:81–82
Andrew JG (1983) Biomechanical measures of muscular effort. Med Sci Sports Exerc 15:199–207
Avis FJ, Hoving A, Toussaint HM (1985) A dynamometer for the measurement of force, velocity, work and power during an explosive leg extension. Eur J Appl Physiol 54:210–215
Belli A, Rey S, Bonnefoy R, Lacour J-R (1992) A simple device for kinematic measurements of human movement. Ergonomics 35:177–186
Bosco C (1993) Test di valutazione della donna nella pratica del giuoco del calcino. In: Cambi R, Paterni M (eds) II calcio femminile, a spetti medici e tecnici. Atti del Convegno Nazionale, Figc Publisher, Rome, pp 219–230
Bosco C, Komi PV (1979a) Potentiation of mechanical behaviour of the human skeletal muscle through prestretching. Acta Physiol Scand 106:467–472
Bosco C, Komi PV (1979b) Mechanical characteristics and fiber composition of human leg extensor muscles. Eur J Appl Physiol 41:275–284
Bosco C, Viitasalo J, Komi PV, Luhtanen P (1982) Combined effect of elastic energy and myoelectrical potentiation during stretch-shortening cycle exercise. Acta Physiol Scand 114:543–550
Bosco C, Luhtanen P, Komi PV (1983a) A simple method for measurement of mechanical power in jumping. Eur J Appl Physiol 50:273–282
Bosco C, Mognoni P, Luhtanen P (1983b) Relationship between isokinetic performance and ballistic movement. Eur J Appl Physiol 51:357–364
Bosco C, Rusko H, Hirvonen J (1986) The effects of extra loads conditioning on muscle performance in athletes. Med Sci Sports Exerc 18:415–419
Cavagna GA, Dusman B, Margaria R (1968) Positive work done by a previously stretched muscle. J Appl Physiol 24:21–32
Coyle EF, Costill DL, Lesmes GR (1979) Leg extension power and muscle fiber composition. Med Sci Sports 11:12–15
De Koning FL, Binkhorst RA, Visses ACA, Vos JA (1982) Influence of static strength training on force-velocity relationship of arm flexors. Int J Sports Med 3:25–28
Haffajee D, Mortiz U, Svantesson G (1972) Isometric knee extension strength as a function of joint angle, muscle length and motor unit activity. Acta Orthop Scand 43:138–147
Kaneko M (1970) The relation between force, velocity and mechanical power in human muscle. Res J Phys Educ 14:143–147
Kraemer WJ (1992) Hormonal mechanisms related to the expression of muscular strength and power. In: Komi PV (ed) Strength and power in sport, Scientific Publications, Oxford, pp 64–67
Mero A, Luhtanen P, Viitasalo JT, Komi PV (1981) Relationship between the maximal running velocity, muscle fiber characteristics, for production of force relaxation of sprinters. Scand J Sports Sci 3:16–22
Milner-Brown HS, Stein RB, Lee RG (1975) Synchronistion of human motor units: possible roles of exercise and supra spinal reflex. Electroencephalogr Clin Neurophysiol 38: 245–254
Nicholas J (1984) The value of sports profiling. Clin Sport Med 3:3–10
Perrine JJ, Edgerton VR (1978) Muscle force-velocity and powervelocity relationships under isokinetic loading. Med Sci Sports 10:159–166
Rodahl K, Horwarth SM (1962) Muscle as a tissue. McGraw-Hill, New York
Sale DG (1991) Testing strength and power. In: MacDougall D, Wenger HA, Green HJ (Eds) Physiological testing of high performance athlete. Human Kinetics, Champaign, Ill., pp 21–106
Sale DG, MacDougall D (1981) Specificity in strength training: a review for coach and athlete. Can J Appl Sport Sci 6:87–92
Thorstensson A (1976) Muscle strength, fiber types and enzyme activities in man. Acta Physiol Scand 98 [Suppl 443]:1–45
Thorstensson A, Larson L, Tesch P, Karlsson J (1977) Muscle strength and fiber composition in athletes and sedentary men. Med Sci Sports 9:26–30
Tihanyi J, Apor P, Fekete G (1982) Force-velocity power characteristics and fiber composition in human knee extensor muscles. Eur J Appl Physiol 48:331–343
Tornvall G (1963) Assessment of physical capabilities with special reference to the evaluation of maximal working capacity. Acta Physiol Scand 58 [Suppl. 201]:1–101
Weiss LW, Cureton KJ, Thompson FN (1983) Comparison of serum testosterone and androstenedione responses to weight lifting in men and women. Eur J Appl Physiol 50:413–419
Williams JH, Barnes WF, Signorile JF (1988) A constant load ergometer for measuring peak power output and fatigue. J Appl Physiol 65:2343–2348
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Bosco, C., Belli, A., Astrua, M. et al. A dynamometer for evaluation of dynamic muscle work. Europ. J. Appl. Physiol. 70, 379–386 (1995). https://doi.org/10.1007/BF00618487
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DOI: https://doi.org/10.1007/BF00618487