passive muscle stretching . Exp Brain Res . 2001 ; 137 : 163 – 169 . PubMed ID: 11315544 doi:10.1007/s002210000648 11315544 10.1007/s002210000648 29. Magnusson SP , Aagard P , Simonsen E , Bojsen-Møller F . A biomechanical evaluation of cyclic and static stretch in human skeletal muscle
Genki Hatano, Shigeyuki Suzuki, Shingo Matsuo, Satoshi Kataura, Kazuaki Yokoi, Taizan Fukaya, Mitsuhiro Fujiwara, Yuji Asai and Masahiro Iwata
Walter Herzog, Timothy R. Leonard, Venus Joumaa and Ashi Mehta
According to the cross-bridge theory, the steady-state isometric force of a muscle is given by the amount of actin–myosin filament overlap. However, it has been known for more than half a century that steady-state forces depend crucially on contractile history. Here, we examine history-dependent steady-state force production in view of the cross-bridge theory, available experimental evidence, and existing explanations for this phenomenon. This is done on various structural levels, ranging from the intact muscle to the myofibrillar and isolated contractile protein level, so that advantages and limitations of the various preparations can be fully exploited and overcome. Based on experimental evidence, we conclude that steady-state force following active muscle stretching is enhanced, and this enhancement has a passive and an active component. The active component is associated with the cross-bridge kinetics, and the passive component is associated with a calcium-dependent increase in titin stiffness.
Markus Tilp, Simon Steib, Gudrun Schappacher-Tilp and Walter Herzog
Force enhancement following muscle stretching and force depression following muscle shortening are well-accepted properties of skeletal muscle contraction. However, the factors contributing to force enhancement/depression remain a matter of debate. In addition to factors on the fiber or sarcomere level, fiber length and angle of pennation affect the force during voluntary isometric contractions in whole muscles. Therefore, we hypothesized that differences in fiber lengths and angles of pennation between force-enhanced/depressed and reference states may contribute to force enhancement/depression during voluntary contractions. The purpose of this study was to test this hypothesis. Twelve subjects participated in this study, and force enhancement/depression was measured in human tibialis anterior. Fiber lengths and angles of pennation were quantified using ultrasound imaging. Neither fiber lengths nor angles of pennation were found to differ between the isometric reference contractions and any of the force-enhanced or force-depressed conditions. Therefore, we rejected our hypothesis and concluded that differences in fiber lengths or angles of pennation do not contribute to the observed force enhancement/depression in human tibialis anterior, and speculate that this result is likely true for other muscles too.
Molly B. Johnson and Richard E.A. Van Emmerik
Sensory feedback from the vestibular system and neck muscle stretch receptors is critical for the regulation of postural control. The postural relationship of the head to the trunk is a major factor determining the integration of sensory feedback and can be interfered with by varying head orientation. This study assessed how 60-s of standing with the head neutral, flexed, or extended impacted postural stability during upright stance and during forward lean in 13 healthy participants (26 ±5 years old). During both quiet upright stance and maximal forward lean, head extension increased postural center of pressure (COP) velocity and decreased the COP time-to-contact the anterior stability boundary compared with the head neutral condition. Head flexion did not differ from head neutral for either of the stance conditions. This study demonstrates that interfering with the head-trunk relationship by adopting extended, but not flexed, head orientations interferes with postural control that may impact postural stability during both quiet upright stance and maximal forward lean conditions.
from what we found. The aim was to explore residual force enhancement properties of a muscle across its entire length and for all parts of the force–length relationship. While doing these experiments, I realized that passive force following active muscle stretching (and deactivation of the muscle) was
Max Pietrzak and Niels B.J. Vollaard
intensity during hamstring stretch for a common ROM, 17 , 31 it was postulated that it may have a significant role in afferent modulation of stretch tolerance. 18 , 25 Compared to muscle stretching protocols, there has been relatively little research investigating utilization of neurodynamic techniques on
Laura A. Verbruggen, Melissa M. Thompson and Chris J. Durall
fasciitis. Treatment allocation was not randomized. Subjects were placed in a calf muscle stretching plus low-Dye taping group (LDT) or a calf muscle stretching only group (control). 92 subjects (M = 37, F = 37; mean age 50 [ ± 14]) clinically diagnosed with plantar fasciitis. Randomly assigned to low
Mariam A. Ameer and Qassim I. Muaidi
with dorsiflexed ankle from standing position 19 (Figures 2 – 4 ). All stretches were performed with assistance from the researcher to maintain the stretching positions but within the limit of each participant, to prevent injury. Figure 2 —Quadriceps muscle stretching procedure. Figure 3 —Hamstring
Yaser Alikhajeh, Elyas Barabadi and Gholam Rasul Mohammad Rahimi
. Shoulders at 90° flexion and with extended elbows. • Activity: Slow and prolonged expiration through the mouth over the water; afterward, the mouth is immersed in water, and then the nose is immersed in water. All stretching exercises were held for 30 seconds each. Exercise 2: Hamstring muscles stretching
Neil Chapman, John Whitting, Suzanne Broadbent, Zachary Crowley-McHattan and Rudi Meir
also observed that regardless of stretch condition, intensity of EMG signals before, during, and following active muscle stretching were smaller than those in the isometric reference contractions. Researchers suggest that voluntary inhibition due to the large size of the muscles may influence these