Relationship between morphometric and mechanical properties of superficial lumbosacral soft tissue layers in healthy young adults.

Introduction: It is commonly considered that myotonometry is a non-invasive method capable of quantifying linear elastic and viscoelastic properties of the myofascial tissue through the application of a weak mechanical impulse to the surface of the skin. However, before the impulse can reach the myofascial tissue, it must cross more superficial tissues such as the skin and subcutaneous tissue (ST). All these superficial tissues have different distributions and organizations of structural components. Therefore, the study aimed to examine the potential relationships between the mechanical and morphometric properties of various superficial soft tissues surrounding the lumbar multifidus muscle (LM). Methods: Myotonometric measurements of dynamic stiffness, logarithmic decrement, and creep, and ultrasonographic measurements of thickness and echogenicity of cutaneous, subcutaneous, perimuscular tissue, and LM were obtained from 50 healthy individuals in the resting prone position and during contralateral arm lift. Results: The most important findings were that in both the relaxed and contracted LM state, the dynamic stiffness strongly negatively (r = -0.69; p < 0.001 in relaxation, r = -0.83; p < 0.001 in contraction) and creep strongly positively (r = 0.79; p < 0.001 in relaxation, r = 0.85; p < 0.001 in contraction) correlated with the thicknesses of the ST. Similar but weaker correlations were noticed between both these measures and the perimuscular tissue thickness. Elasticity was uncorrelated to the thicknesses of the tissues. With LM contraction (change from the relaxed to contracted state), the relative increase in dynamic stiffness was correlated with the relative decrease in dermis (r = -0.51; p < 0.001) and ST (r = -0.47; p = 0.001) thickness, and with the relative increase in LM (r = 0.36; p = 0.010) thickness. Moreover, the relative decrease (thinning) in the ST thickness was correlated with the relative increase in logarithmic decrement (i.e., decrease in soft tissue elasticity, r = -0.37, p = 0.011). The mechanical properties of the soft tissues were not related to their echogenicity. Discussion: In conclusion, the thicker the subcutaneous and perimuscular layers, the lesser the stiffness and the greater the time-dependent deformation to the external force of the tissues surrounding the LM during its relaxation and isometric contraction. Moreover, the greater the thinning of the ST and the thickening of the LM during its contraction, the higher the increase in lumbosacral tissue stiffness and the decrease in elasticity. Therefore, one should consider the thickness of the ST before planning or analyzing the outcomes of myotonometric or other external biomechanical measurements to avoid drawing the wrong conclusions about the mechanical properties of the myofascial tissue.

Motor Unit Force Potentiation and Calcium Handling Protein Concentration in Rat Fast Muscle After Resistance Training.

Post-tetanic potentiation (PTP) of force depends on intramuscular Ca2+ levels and sensitivity and may be affected by fatigue. The aim of this study was to determine the ability of isolated fast fatigue-resistant (FR) and fast-fatigable (FF) motor units (MUs) to potentiate force evoked with single and 40-Hz electrical stimulation after 5 weeks of voluntary weight-lifting training. Tetanic contractions evoked by gradually increasing (10-150 Hz) stimulation frequency served as conditioning stimulation. Additionally, the concentration of myosin light chain kinase and proteins engaged in calcium handling was measured in rat fast medial gastrocnemius muscle. After the training, the potentiation of twitch force and peak rate of force development was increased in FF but not FR MUs. Force potentiation of 40-Hz tetanic contractions was increased in both fast MU types. After the training, the twitch duration of FR MUs was decreased, and FF MUs were less prone to high-frequency fatigue during conditioning stimulation. Muscle concentration of triadin was increased, whereas concentrations of ryanodine receptor 1, junctin, FKBP12, sarcoplasmic reticulum calcium ATPase 1, parvalbumin, myosin light chain kinase, and actomyosin adenosine triphosphatase content were not modified. After short-term resistance training, the twitch contraction time and twitch:tetanus force ratio of FR MUs are decreased, and PTP ability is not changed. However, PTP capacity is increased in response to submaximal activation. In FF MUs increase in PTP ability coexists with lesser fatigability. Further work is required to find out if the increase in triadin concentration has any impact on the observed contractile response.

Jumping Height Does Not Increase in Well Trained Volleyball Players After Transcutaneous Spinal Direct Current Stimulation.

Transcutaneous spinal direct current stimulation (tsDCS) increases corticospinal and spinal reflex excitability, and may be a new tool for increasing muscle explosive performance in sports training. The aim of the study was to evaluate whether tsDCS can enhance jumping ability in trained humans practicing volleyball. Twenty eight participants completed the study, including 21 men and 7 women. We investigated the effects of a single 15-minute session of sham, anodal, and cathodal tsDCS over spine and shoulder on repeated counter movement jump (CMJ) and squat jump (SJ) performance at 0, 30 and 60 min post-stimulation. The order of SJs and CMJs sets in each session was randomized. Each SJ and CMJ set consisted of 3 jumps. The break between each attempt was 1 min and the interval between the sets was 3 min. Two-way repeated measures ANOVA did not show effect of time, nor stimulation method, nor stimulation method × time interactions on SJ (time: F ( 1 . 8,142 . 1 ) = 1.054; p = 0.346, stimulation: F ( 2,78 ) = 0.019; p = 0.981, stimulation × time: F ( 3 . 6,142 . 1 ) = 0.725; p = 0.564) or CMJ (time: F ( 1 . 8,140 . 9 ) = 2.092; p = 0.132, stimulation: F ( 2,78 ) = 0.005; p = 0.995, stimulation × time: F ( 3 . 6,140 . 9 ) = 0.517; p = 0.705) performance. Single session of tsDCS over spine and shoulder does not increase jumping height in well-trained volleyball players. This is an important finding for coaches and strength conditioning professionals for understanding the practical utility of tsDCS for enhancing muscular explosiveness.

Short-Term Effects of Kinesio Taping® on Electromyographic Characteristics of Paraspinal Muscles, Pain, and Disability in Patients With Lumbar Disk Herniation.

Context: Kinesio taping® (KT) is a therapeutic modality frequently used in the clinical practice for the treatment of various musculoskeletal disorders. It is often applied in patients with chronic low back pain to decrease pain and improve functional capacity. However, it is not known, whether thoracolumbar fascia KT technique can decrease back pain, restore normal activity of paraspinal muscles, and improve functional capacity in patients with lumbar disk herniation (LDH). Objective: To evaluate the impact of 7-day new KT stabilizing application on lumbar paraspinal muscles function, pain perception, and disability in patients with LDH. Design: A randomized controlled trial. Setting: Human Performance Laboratory. Patients: A number of 38 patients with LDH were randomized into KT (n = 19) and placebo taping (n = 19) groups. Interventions: Both groups received the same "x" type application running over the back along fibers of superficial lamina of the posterior layer of thoracolumbar fascia. Main Outcome Measures: The primary outcome measures were flexion-relaxation and extension-relaxation ratios calculated from electromyographic activity of lumbar multifidus and longissimus thoracic muscles. Pain intensity rating (Quadruple Visual Analogue Scale), pressure pain thresholds of the lower back, Roland-Morris Disability Questionnaire score, back extension force, and flexion range of motion (ROM) were among secondary outcomes. Results: KT application did not affect the lumbar multifidus and longissimus thoracic muscles flexion-relaxation and extension-relaxation ratios, lower back pressure pain thresholds, back flexion ROM, and back extension force (no group × time interaction [GTI]). KT and placebo taping comparably decreased disability level (time effect: F1,36 = 22.817, P < .001; GTI: F1,36 = 0.189, P = .67), average pain (time effect: F1,36 =39.648, P < .001; GTI: F1,36 = 2.553, P = .12), and the worst pain (time effect: F1,36 = 36.039, P < .001; GTI: F1,36 = 0.003, P = .96) intensity. Conclusion: Seven-day KT does not normalize lumbar paraspinal muscle function and is not superior to placebo in reducing disability and pain intensity in patients with LDH.

Effects of aging on mechanical properties of sternocleidomastoid and trapezius muscles during transition from lying to sitting position-A cross-sectional study.

AIM: The aim of this study was to analyze the effects of aging on the viscoelastic properties of the upper trapezius (UT) and the sternocleidomastoid (SCM) muscle during transition from lying to sitting position. MATERIALS AND METHODS: The study included 39 older (mean age 67±5.9years) and 36 younger (21.1±1.8years) women. Tone, stiffness and elasticity of the UT and the SCM were measured by means of myotonometry (MyotonPRO) in lying and then, in sitting position. The results were compared using two-way analysis of variance. RESULTS: Irrespective of the position, older women presented with significantly higher muscle tone, stiffness and elasticity than younger subjects (P<0.05). In both groups, the transition from lying to sitting position resulted in a decrease (P<0.05) in the tone and stiffness, but not the elasticity (P>0.05) of the SCM, and stimulated an increase in the tone, stiffness and elasticity of the UT (P<0.05). The degree of changes in both study groups was similar, except from the absolute value of the UT elasticity, significantly higher increase in older women than in younger subjects (P<0.05). CONCLUSION: Age contributes to an increase in the stiffness and tone of the UT and the SCM, as well as to a decrease in the elasticity of these muscles in female subjects. In contrast, age exerts only a slight effect on the mechanical properties of both muscles during transition from lying to sitting position.

The effect of the Kinesio Taping method on spinal motion and physiological spinal curvatures. Literature review.

BACKGROUND: The Kinesiology Taping / Kinesio Taping (KT) method has become more and more popular in recent years. Many studies have been developed to demonstrate the application of this method in numerous fields of medicine. Despite its continuous development, several issues pertaining to the legitimacy of its application and mechanisms of its operation still need to be addressed. The aim of this study is to analyse the available literature in terms of the effect of KT on the spinal motion and physiological spinal curvatures. This study is based on a method of analysing bibliographic databases such as: SPORTDiscus, Medline, ScienceDirect, EBSCOhost, and Google Scholar. RESULTS AND CONCLUSIONS: There were found seven research articles that observe the criteria of this study's aim. Four of those research articles were devoted to the motion of the lumbar spinal segment, the other two discussed the motion of the cervical spinal segment and one of them concentrated on the lumbar lordosis. None of those research articles included any information on negative effect of this method. The effect of KT on assessed parameters is barely noticeable. Therefore, it is necessary to conduct further research in respect of the effect of the Kinesiology Taping method on the spinal motion and physiological spinal curvatures.

A comparison of the effects of deep tissue massage and therapeutic massage on chronic low back pain.

INTRODUCTION: This study compared the effectiveness of two different kind of massage: therapeutic and deep tissue on chronic low back pain. METHODS: The research was made on 26 patient aged from 60 to 75 years who were separated into 2 groups: I [n=13] and II [n=13]. Group I had therapeutic massage [TM] which uses effleurage, petrissage, tapping and friction. Group II had deep tissue massage [DTM] which uses oblique pressure, a combination of lengthening and cross-fiber strokes, anchor and stretch, freeing muscle from entrapment. TM and DTM lasted for 10 days, each 30 min and were made by qualify massage therapist. Both groups did not have other treatment. Outcome measures obtained at baseline and after treatment consisted of Modified Oswestry Low Back Pain Disability Index [ODI], Quebec Back Pain Disability Scale[QBPD] and Visual Analog Scale [VAS]. RESULTS: There was not statistically significant differences between groups according to age and BMI. Statistically significant differences were noted after TM in every test [ODI p=0.010; QBPD p<0.001; VAS p<0.001] and after DTM in every test [ODI p<0.001; QBPD p<0.001; VAS p<0.001]. DTM was statistically significant better therapy than TM in ODI [p=0.038] and VAS [p=0.015]. Further research is needed to verify the results.