Muscle soreness that has a delayed onset is common feature among both athletes and untrained individuals who engage in unusual exercises. This study was designed to provide additional morphological data assess the relevance significance of our previous findings sore muscles contain fibers with disorganized myofibrillar material. biopsies were obtained from 12 males (mean age 25 +/- 7 years), suffered severe their thigh 18--72 h following eccentric bicycle exercise. Their strength performance...

It is well documented in both animal and human studies that unaccustomed, particularly eccentric, muscle exercise may cause damage of fiber contractile cytoskeletal components. These injuries typically include: Z-band streaming dissolution, A-band disruption, disintegration the intermediate filament system, misalignment myofibrils. The mechanical basis for this suggested to be due strain magnitude rather than absolute stress imposed on fiber. We hypothesize eccentric contraction-induced...

Contractile properties of rabbit tibialis anterior muscles were measured after eccentric contraction to investigate the mechanism muscle injury. In first experiment, two groups strained 25% fiber length at identical rates. However, because timing imposed change relative activation was different, experienced dramatically different forces. Because maximum tetanic tension and other contractile parameters 30 min cyclic activity with either strain pattern (P > 0.4), we concluded that damage...

Abstract The mechanical properties of isolated single muscle fiber segments were measured in cells obtained from patients undergoing surgery for correction flexion contractures secondary to static perinatal encephalopathy (cerebral palsy). “Normal” with intact neuromuscular function also mechanically tested. Fiber taken subjects spasticity developed passive tension at significantly shorter sarcomere lengths (1.84 ± 0.05 μm, n = 15) than fibers normal (2.20 0.04 35). Elastic modulus the...

Contractile and morphological properties were measured in the rabbit tibialis anterior muscle 1 h after isometric contraction (IC), passive stretch (PS), or eccentric (EC). Maximal tetanic tension (Po) was reduced 30 min of PS (P less than 0.001), IC EC 0.0001). However, magnitude force deficit a function treatment method. After cyclic PS, Po decreased by 13%, whereas EC, 31 69%, respectively. The time course decline various groups suggested that EC-induced injury occurred during first few...

The time course of loss the 55,000-Da intermediate filament protein desmin was measured in rabbit muscles subjected to cyclic eccentric conrtraction. Rabbit extensor digitorum longus (EDL) and tibialis anterior (TA) were examined 5 or 15 min after exercise 1 h day 30 an protocol (n = 16 rabbits). earliest change noted a significant labeling 2.5 +/- 0.63% EDL muscle fibers (P < 0.005) initiation exercise. Some TA fiber also apparent at this period (0.24 0.19%), but magnitude not...

We studied the effect of flurbiprofen, a non-steroidal anti-inflammatory drug, on muscles that had been subjected to exercise-induced injury. The anterior compartment in limbs rabbits were cyclically activated as ankle was simultaneously moved through passive plantar flexion every two seconds for thirty minutes. This treatment imposed acute lengthening (eccentric contractions) maximally contracted compartment. After eccentric contraction-induced muscle injury, one group treated with oral...

1. Human extensor carpi radialis brevis (ECRB) sarcomere length was measured intraoperatively in five subjects using laser diffraction. 2. In a separate cadaveric study, ECRB tendons were loaded to the muscle's predicted maximum tetanic tension, and tendon strain estimate active shortening at expense of lengthening. 3. As wrist joint passively flexed from full extension flexion, increased 2.6 3.4 microns rate 7.6 nm/deg angle rotation. Correcting for elongation during muscle activation...

Abstract The passive mechanical properties of small muscle fiber bundles obtained from surgical patients with spasticity ( n = 9) and without neuromuscular disorders 21) were measured in order to determine the relative influence intracellular extracellular components. For both types patient, tangent modulus was significantly greater compared identical tests performed on isolated single cells P < 0.05). However, difference between much normal tissue than spastic tissue. (462.5 ± 99.6 MPa)...

Abstract An experimental model for inducing chronic Achilles paratenonitis with tendinosis in the rabbit is presented. Thirteen rabbits were exercised a kicking machine producing passive flexions and extensions of ankle joint. Active contractions triceps surae muscles induced by electric stimulation via surface electrodes. The animals 5 to 6 weeks, rate 150 per minute 2 h, three times week. Light microscopic examination showed degenerative changes tendon, increased number capillaries,...

Sarcomere length was measured in flexor carpi ulnaris (FCU) muscles from patients with severely spastic wrist flexion contractures (n = 6), as well radial nerve injury and a normally innervated FCU 12). Spastic had extremely long sarcomere lengths the fully flexed (3.48 +/- 0.44 microm) compared to of (2.41 0.31 microm). In three contractures, slope length-joint angle relationship found be, essentially, normal (0.017 0.005 microm/degree, n 3) suggesting that serial number (and therefore...

The peripheral adaptation process associated with repeating eccentric training over a longer period of time was studied in m. vastus lateralis eleven healthy males aged 24 +/- 4 years. maximal dynamic concentric muscle strength only slightly improved after 8 weeks training. However, work capacity dramatically increased (375%). A stint immediately fulfilled caused selective glycogen depletion from the type 28 fibers. An number 2C fibers observed. ultrastructure analysis showed an essentially...

This study investigates the dynamic and resting intramuscular pressures associated with eccentric concentric exercise of muscles in a low-compliance compartment. The left righ leg anterior compartments eight healthy males (ages 22–32 yr) were exercised by either or contractions same load (400 submaximal at constant rate, 20/min for 20 min corresponding to 15% individual maximal dorsiflexion torque). Tissue fluid measured slit-catheter technique before, during, after exercise. Average peak...

Background Trigger finger is characterized by sometimes painful snapping or locking when flexing the finger. Although trigger frequently seen in clinical practice, no standard treatment protocol has been established as “best practice.” Objective The aim of this study was to achieve consensus on a multidisciplinary guideline for Design A European Delphi strategy initiated. Systematic reviews reporting effectiveness surgical and nonsurgical interventions were conducted used an evidence-based...

Abstract With use of immunohistochemistry and antibodies to substance P calcitonin gene‐related peptide, nerve fibers showing P‐like peptide‐like immunoreactivity were demonstrated at the origin extensor carpi radialis brevis muscle in patients with tennis elbow (n = 6) healthy controls 6). The distributed association a subpopulation small blood vessels bundles but not tunica media‐adventitia junction arterioles. There no inflammatory‐cell infiltrates few solitary mast cells. present study...

The time course of muscle contractile and cellular properties was studied in rabbit ankle flexor muscles after injury produced by eccentric exercise. Cyclic exercise increasing the tibiotarsal angle while activating peroneal nerve use transcutaneous electrodes. Muscle were measured 1, 2, 3, 7, 14, 28 days to define changes injury. A control group receiving only isometric contraction used study effect cyclic activation itself. magnitude torque decline 1 day same with or exercise, but resulted...

Delayed muscle soreness in man is known to be attributed a disorganization of the myofibrils. Our aim present study was investigate whether intermediate filament system affected as well. Biopsies were taken from right m. vastus lateralis six males (aged 23 ± 3 years) suffering severe post-exercise their thigh muscles. Intermediate protein visualized by indirect immunofluorescence microscopy using an antibody specific desmin. A typical finding biopsies days after exercise abundant...