Abstract
Tendon stiffness increases as the magnitude and rate of loading increases, according to its viscoelastic properties. Thus, under some loading conditions tendons should become exceptionally stiff and act almost as rigid force transducers. Nonetheless, observations of tendon behavior during multi-joint sprinting and jumping tasks have shown that tendon strain increases whilst muscle strain decreases as the loading intensity increases. The purpose of the current study was to examine the influence of external loading intensity on muscle–tendon unit (MTU) behavior during a high-speed single-joint, stretch-shortening cycle (SSC) knee extension task. Eighteen men (n = 9) and women (n = 9) performed single-leg, maximum intensity SSC knee extensions at loads of 20, 60 and 90 % of their one repetition maximum. Vastus lateralis fascicle length (L f) and velocity (v f) as well as MTU (L MTU) and tendinous tissue (L t) length were measured using high-speed ultrasonography (96 Hz). Patellar tendon force (F t) and rate of force development (RFDt) were estimated using inverse dynamics. Results showed that as loading intensity increased, concentric joint velocity and shortening v f decreased whilst F t and RFDt increased, but no significant differences were observed in eccentric joint velocity or peak L MTU or L f. In addition, the tendon lengthened significantly less at the end of the eccentric phase at heavier loads. This is the first observation that tendon strain decreases significantly during a SSC movement as loading intensity increases in vivo, resulting in a shift in the tendon acting as a power amplifier at light loads to a more rigid force transducer at heavy loads.
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References
Abellaneda S, Guissard N, Duchateau J (2009) The relative lengthening of the myotendinous structures in the medial gastrocnemius during passive stretching differs among individuals. J Appl Phys 106:169–177
Baratta R (1991) The effect of tendon viscoelastic stiffness on the dynamic performance of isometric muscle. J Biomech 24:109–116
Bobbert M (2001) Dependence of human squat jump performance on the series elastic compliance of the triceps surae: a simulation study. J Exp Biol 533:533–543
Bobbert M, Ettema G, Huijing P (1990) The force–length relationship of a muscle–tendon complex: experimental results and model calculations. Euro J Appl Physiol O 61:323–329
Cormie P, McBride J, McCaulley G (2008) Power–time, force–time, and velocity–time curve analysis during the jump squat: impact of load. J Appl Biom 24:112–120
Earp J, Cormie P, Newton R (2013) Knee angle-specific EMG normalization: the use of polynomial based EMG–angle relationships. J Electromyogr Kinesiol 23:238–244
Ettema G (1996) Mechanical efficiency and efficiency of storage and release of series elastic energy in skeletal muscle during stretch–shorten cycles. J Exp Biol 199:1983–1997
Ettema G, Huijing P (1994) Skeletal muscle stiffness in static and dynamic contractions. J Biom 27:1361–1368
Finni T (2006) Structural and functional features of human muscle–tendon unit. Scand J Med Sci Spor 16:147–158
Finni T, Ikegawa S, Lepola V, Komi P (2001) In vivo behavior of vastus lateralis muscle during dynamic performances. E J Sport Sci 1:1–13
Finni T, Ikegawa S, Lepola V, Komi P (2003) Comparison of force–velocity relationships of vastus lateralis muscle in isokinetic and in stretch–shortening cycle exercises. Acta Physiol Scand 177:483–491
Fukunaga T, Kawakami Y, Kubo K, Kanehisa H (2002) Muscle and tendon interaction during human movements. Exerc Sport Sci R 30:106–110
Hawkins D, Hull M (1990) A method for determining lower extremity muscle–tendon lengths during flexion/extension movements. J Biomech 23:7
Hermie JH (1996) The state of the art on sensors and sensor placement procedures for surface electromyography: a proposal for sensor placement procedures. Roessingh R&D, Netherlands
Ishikawa M, Komi P (2004) Effects of different dropping intensities on fascicle and tendinous tissue behavior during stretch–shortening cycle exercise. J Appl Phys 96:848–852
Ishikawa M, Komi P (2007) The role of the stretch reflex in the gastrocnemius muscle during human locomotion at various speeds. J Appl Phys 103:1030–1036
Ishikawa M, Finni T, Komi P (2003) Behaviour of vastus lateralis muscle tendon during high intensity SSC exercises in vivo. Acta Physiol Scand 178:205–213
Ishikawa M, Niemela E, Komi P (2005) Interaction between fascicle and tendinous tissues in short-contact stretch–shortening cycle exercise with varying eccentric intensities. J Appl Phys 99:217–223
Ishikawa M, Komi P, Finni T, Kuitunen S (2006) Contribution of the tendinous tissue to force enhancement during stretch shortening cycle exercise depends on the prestretch and concentric phase intensities. J Electromyogr Kinesiol 16:423–431
Ishikawa M, Pakaslahti J, Komi P (2007) Medial gastrocnemius muscle behavior during human running and walking. Gait Posture 25:380–384
Ito M, Kawakami Y, Ichinose Y, Fukashiro S, Fukunaga T (1998) Nonisometric behavior of fascicles during isometric contractions of a human muscle. J Appl Phys 85:1230–1235
Kubo K, Kawakami Y, Fukunaga T (1999) Influence of elastic properties of tendon structures on jump performance in humans. J Appl Phys 87:2090–2096
Kubo K, Kanehisa H, Fukunaga T (2005) Effects of viscoelastic properties of tendon structures on stretch shortening cycle exercise in vivo. J Sports Sci 23:851–860
Kubo K, Morimoto M, Komuro T, Tsunoda N, Kanehisa H, Fukunaga T (2007) Influences of tendon stiffness, joint stiffness, and electromyographic activity on jump performances using single joint. Euro J Appl Physiol 99:235–243
Kurokawa S, Fukunaga T, Fukashiro S (2001) Behavior of fascicles and tendinous structures of human gastrocnemius during vertical jumping. J Appl Phys 90:1349–1358
Magnusson S, Narici M, Maganaris C, Kjaer M (2008) Human tendon behaviour and adaptation, in vivo. J Physiol 586:71–81
Nagano A, Komura T, Fukashiro S (2004) Effects of the length ratio between the contractile element and the series elastic element on an explosive muscular performance. J Electromyogr Kinesiol 14:197–203
Netti P, Ronca D, Ambrosio L, Nicolais L (1996) Structure–mechanical properties relationship of natural tendon and ligaments. J Mater Sci 7:525–530
Reeves N, Narici M (2003) Behavior of human muscles fascicles during shortening and lengthening contractions in vivo. J Appl Biom 95:1090–1097
Roberts T (2002) The integrated function of muscles and tendons during locomotion. Comp Biochem Physiol A 133:1087–1099
Roeleveld K, Baratta R, Solomonow M, Van Soest A, Huijing P (1993) Role of tendon properties on the dynamic performance of different isometric muscles. J Appl Phys 74:1348–1355
Sousa F, Ishikawa M, Vilas-Boas J, Komi P (2007) Intensity- and muscle-specific fascicle behavior during human drop jumps. J Appl Phys 102:382–389
Van Ingen Schenau G, Bobbert M, Haan A (1997) Does elastic energy enhance work and efficiency in the stretch–shortening cycle? J Appl Biom 13:389–415
Van Soest A, Huijing P, Solomonow M (1995) The effect of tendon on muscle force in dynamic isometric contractions, a simulation study. J Biomech 28:801–807
Visser H, Bobbert M, Huijing P (1990) Length and moment arm of human leg muscles as a function of knee and hip-joint angles. Eur J Appl Physiol 61:7
Winter D (1990) Biomechanics and motor control of human movement. Wiley, Toronto
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Communicated by William J. Kraemer.
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Earp, J.E., Newton, R.U., Cormie, P. et al. The influence of loading intensity on muscle–tendon unit behavior during maximal knee extensor stretch shortening cycle exercise. Eur J Appl Physiol 114, 59–69 (2014). https://doi.org/10.1007/s00421-013-2744-2
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DOI: https://doi.org/10.1007/s00421-013-2744-2