Effects of different dropping intensities on fascicle and tendinous tissue behavior during stretch-shortening cycle exercise

Abstract

This study examined whether the elasticity of the tendinous tissues plays an important role in human locomotion by improving the power output and efficiency of skeletal muscle. Ten subjects performed one-leg drop jumps (DJ) from different dropping heights with a constant rebound height. The fascicle length of the vastus lateralis muscle was measured by using real-time ultrasonography during DJ. In the braking phase of the DJ, fascicle lengthening decreased and the tendinous tissue lengthening increased with increased dropping intensity. In the subsequent push-off phase, the shortening of tendinous tissues increased with higher dropping intensity. The averaged electromyographic activities of the preactivation and braking phases increased and those of the push-off phase decreased as the drop height was increased. With higher dropping height but constant submaximal rebound jump, the stretched tendinous tissue length increased with less stretched fascicle during the braking phase. In the subsequent push-off phase, the recoil of tendinous tissues became greater. These results suggest that the increased prestretch intensity has considerable influence on the process of storage and subsequent recoil of the elastic energy during the stretch-shortening cycle action.

Muscle fascicle shortening behaviour of vastus lateralis during a maximal force–velocity test

“…Although the musculoskeletal model used in this study is commonly used in literature Ishikawa and Komi 2004;Finni et al 2001) to dissociate the behaviour of muscles fascicle and tendinous tissues, it has some limitations. The shortening velocity of knee extensor muscles was restricted to the shortening velocity of vastus lateralis muscle, considered as a surrogate of the knee extensor muscles.…”

“…These interactions have been well described in animal (Astley and Roberts 2012;Biewener and Baudinette 1995;Wilson et al 2003) and human locomotion (e.g., walking and running; Cronin and Lichtwark 2013;Fukunaga et al 2001;Ishikawa et al 2007;Lichtwark et al 2007). During exercises involving stretch-shortening cycles, these interactions have been demonstrated to enhance the work produced by the muscle-tendon unit (Ishikawa and Komi 2004;Kawakami et al 2002;Finni et al 2001), to improve the efficiency (Lichtwark and Barclay 2010) and to reduce muscle fibre elongation during the eccentric phase, thereby limiting the risk of strain induced injury (Guilhem et al 2016;Konow et al 2012).…”

Iontophoresis with or without dexamethazone in the treatment of acute Achilles tendon pain

“…The SSC is a combination of an eccentric muscle action (with lengthening of the muscle and tendon), followed immediately by a concentric muscle action (shortening of the muscle-tendon complex) (Bosco et al, 1982b, Komi, 2000, Ishikawa and Komi, 2004.…”

Vastus Lateralis Fascicle Length Changes During Stair Ascent and Descent

“…However, during other activities, the manner in which the knee extensor muscles and tendon contribute to the function of the MTC has been studied using ultrasound imaging. [9][10][11]16,23 Ultrasound imaging of skeletal muscles provides a real-time, noninvasive, and reliable measurement of intact human muscle fascicle length while the muscle is at rest or during movement.…”

“…12,16,17,21 But, more importantly for understanding the mechanical behavior of the muscle during movement, similar interactions between the muscle fascicle and tendon occur during dynamic muscle actions, as those in walking and jumping. 9,10,15 The ability of the tendon to lengthen when the muscle is activated and, subsequently, to shorten suggests that the tendon stores considerable energy as it is lengthened so that it can contribute to movement.…”