Magnitude of changes in muscle endurance in the Biering-Sorensen test and changes in balance in subjects with LBP treated with muscle energy techniques.

Purpose: Manual therapy is used as a conservative treatment for people with low back pain (LBP). The scale of the problem encourages the search for the most effective methods to assess of manual treatment. Therefore, the aim of the study was to investigate magnitude of changes in muscle endurance using the Biering-Sorensen test (BST) and to analyse balance in patients with LBP treated with ERS and FRS muscle energy techniques (MET). Methods: The study included fifteen men with LBP (mean age: 42 years) working as automotive assemblers. Endurance of the biceps femoris (BF), gluteus maximus (GM) and erector spinae (ES) muscles were analysed using sEMG during the BST. The level of experienced pain, degree of disability and postural stability were also examined. Results before and after a three-week treatment cycle using MET were compared. Results: The MET therapy resulted in a reduction in pain ( p = 0.001), an improvement in the degree of disability ( p < 0.001) and an increase in the duration of the BST ( p < 0.001). After therapy, the values of the NMFs parameter indicating the degree of fatigue increased, i.e., ES muscle endurance increased, both right ( p = 0.004) and left ( p < 0.001). There was also a statistically significant decrease in the centre of pressure (COP) movement velocity in balance tests. Conclusions: The use of MET in patients with LBP increases muscle endurance, improves postural balance, and reduces pain levels on the VAS and disability levels according to the ODI. MET appears to be a good tool for preventing LBP.

The use of thermal imaging for monitoring the training progress of professional male sweep rowers.

This study assesses the thermal profile of the skin in highly trained rowers and investigates the relationship between resting skin temperature (Ts) and the muscle peak torque (PT) measured in statics at the beginning (autumn) and the end (spring) of the preparatory period. Ten professional male sweep rowers, members of the Polish national rowing team, were investigated. A thermal imaging camera was used to analyze the Ts. The PT of the muscles involved in the rowing cycle were measured isometrically. No significant temperature asymmetries were found, except in front of arms after exercise in the spring (p = 0.0228). In contrast, the PT test in the autumn confirmed the significant asymmetry of the knee joint extensors (p = 0.0192). In spring compared to autumn, Ts in many areas of the body were slightly higher, as was PT of underlying muscles. Significant correlations between resting Ts and PT of the underlying muscles were found. Thermal imaging makes it possible to observe changes in skin temperature and symmetry before and after exercise. At this stage, it does not appear to be a method that, without supporting of other methods such as those assessing muscle function, will allow monitoring of training progress.

The Impulse of Force as an Effective Indicator of Exercise Capacity in Competitive Rowers and Canoeists.

The aim of the research was to present the importance of measuring the impulse of force in assessing exercise capacity in professional rowers and canoeists rather than conducting traditional physiological and biochemical analyses. A group of 20 athletes (12 rowers and 8 canoeists) underwent progressive intensity exercise tests in two testing sessions (before and after a training period). During the tests, maximal aerobic capacity, impulse of strength, metabolic indices, and markers of skeletal muscle damage were assessed. Total testosterone, free testosterone, cortisol, interleukin 1,6, and creatine kinase were evaluated in venous blood. The impulse of force at the ventilatory threshold and at the maximum load was correlated with free testosterone and a total testosterone/cortisol ratio during exercise (p ≤ 0.05) and was negatively correlated with cortisol concentration (p ≤ 0.05) in the first testing session (before training intervention). Values were positively correlated with concentration of total testosterone, free testosterone and total testosterone/cortisol, and free testosterone/cortisol ratios during exercise (p ≤ 0.05) in the second testing session (after training intervention). Biochemical indices of overtraining were correlated with maximum oxygen uptake in each session and with the impulse of force at the ventilatory threshold and the maximum load of exercise. Thus, there is an indirect relationship between maximal aerobic capacity and the impulse of force. The measurement of the impulse of force can become a simple and effective method for evaluating the overall exercise capacity of rowers because of its relationship with indices of the load and changes in hormonal indices of anabolic and catabolic processes during exercise. Therefore, it may constitute a replacement for the traditional laboratory measurement of VO2max in highly qualified rowers and canoeists.

Distribution of Young's modulus at various sampling points in a human lumbar spine vertebral body.

BACKGROUND CONTEXT: Mathematical modeling for creating computer spine models is one of the basic methods underlying many scientific publications. The accuracy of strength parameters of tissues introduced into such models translates directly into the reliability of obtained results. Experimental determination of Young's modulus (E) in various areas of spongy bone tissue seems to be crucial for creating a reliable spine model without excessive simplifications in the form of a single E value for the whole vertebral body. PURPOSE: The aim of the study was to determine Young's modulus in different parts of the lumbar vertebral column for samples subjected to compression and bending. STUDY DESIGN: Cylindrical spongy bone tissue samples were subjected to bending and compression strength tests. METHODS: The study included 975 pathologically unchanged samples of spongy bone tissue harvested from the lumbar vertebrae of 15 male donors. The samples were subjected to compression or bending strength tests and then Young's modulus was determined for each sample depending on its location in the vertebral body. The samples were tested differently between given locations within one vertebra as well as between vertebrae. RESULTS: Compressed specimens are characterized by highly significantly different Young's modulus values depending on the location in the vertebral body. Samples No. 7 and No. 9 in the anterior part of the vertebral body have highly significantly higher Young's modulus values compared to those in the posterior part of the vertebral body for all lumbar vertebrae. Samples subjected to bending showed significant differences (p<.05) between samples located closer to the vertebral canal (No.16, No.17) and samples located further away (No.14, No.15) with higher values for the samples located in the posterior part of the vertebral body. CONCLUSIONS: Accommodating the anisotropic structure of spongy bone in computer models and the application of different Young's module values for areas within one vertebral body will allow one to obtain realistic results of computer simulations used. CLINICAL SIGNIFICANCE: Determining the exact strength parameters of spongy bone tissue within one vertebra and changes in these properties in subsequent vertebrae will allow to create more accurate computer models of the lumbar spine and the whole spine. This, in turn, will translate into more reliable computer simulations used, among others, to determine the risk of fractures or osteoporotic changes, or simulation of the procedure of spinal fusion.

Electromyographic evaluation of selected muscles during active hip extension in men treated McKenzie method.

PURPOSE: The aim of this study was to evaluate objective results of short-term treatment with the use of electromyography and to determine changes in muscle recruitment during the prone hip extension test in individuals with chronic low back pain who underwent the McKenzie treatment. METHODS: The studied group consisted of 17 male office workers aged 33-55 who underwent two experimental sessions comprising of 3 measurements and the McKenzie method of mechanical diagnosis and therapy. Electromyographic examination of selected muscles was performed during the test in order to assess changes in their activity before and after the McKenzie method and the Visual Analogue Scale was used to assess the level of pain. RESULTS: There was a tendency towards significance at the beginning of activation between the first and second test for the left erector spinae muscle ( p = 0.0684). In 18% of patients, the onset activation time decreased, which is indicative of correct direction of changes. No statistically significant changes were observed in the remaining muscles. Statistical significance ( p = 0.0131) was observed between the first and third test for the left erector spinae muscle. A decrease in the onset activation time was observed in 75% of the subjects. Effectiveness increased by as much as 57%. The level of pain decreased in the third test compared to the first one ( p = 0.0240). However, the change in pain sensations between the first and second test was not statistically significant. CONCLUSIONS: The study showed objective changes in the activation sequence of selected muscles and subjective changes in pain following short term McKenzie therapy.

Evaluation of functional and structural changes affecting the lumbar spine in professional field hockey players.

PURPOSE: The aim of this study was to evaluate functional and structural changes in the lumbar spine which occurred as a consequence of playing field hockey. METHODS: The research group consisted of 20 male professional field hockey players. Computed tomography scans were collected to define the radiological density of the vertebral bodies and to calculate Young's modulus. An electrogoniometer was used to measure the range of movement. Geometric parameters, such as Lumbar Lordosis Angle, Index of Lumbar Lordosis, Whitmann-Ferguson Angle and Anterior Pelvic Tilt, were also measured. RESULTS: The values describing lumbar lordosis increased linearly with years of training and were significantly greater than those reported in the literature. Field hockey players displayed a larger range of flexion, side bending and rotation to the right. An analysis of radiological density discovered significantly high values. An analysis of Young's modulus showed that the vertebral bodies become more fragile. CONCLUSIONS: The results show that overuse changes in the lumbar spine of field hockey players are severe and highly correlated with years of training.