Remobilization with whole-body vibration improves functionality, histomorphometric parameters, and AQP1 expression in the soleus muscle of Wistar rats.

Background: Whole-body vibration (WBV) is used to enhance physical performance in sports and rehabilitation. The present study analyzed the effects of remobilization with WBV on the soleus muscle of Wistar rats. Methods: Twenty-eight animals were separated into four experimental groups (n = 7): CON (control); IM (immobilized); FR (immobilization and free remobilization); and WBV (immobilization and remobilization with WBV). The immobilization of the pelvic limb was carried out according to the standard protocol using a plaster cast for 15 days. For remobilization with WBV, a Frequency of 60 Hz was applied for 10 min, five days a week, for two weeks. After the remobilization period, the animals were euthanized, and the right soleus muscle was dissected followed by processing for histomorphometric analysis and immunolocalization of Aquaporin 1 (AQP1). Results: We observed a reduced larger diameter in IM compared to CON, with restored values in WBV. For the estimation of connective tissue, a significant increase was observed in the immobilized groups, while a reduction was noted in the remobilized groups. AQP1 expression decreased significantly in IM and increased in WBV. Conclusion: Immobilization caused morphofunctional damage to the soleus muscle, and remobilization with WBV is efficient and offers advantages over free remobilization.

Cryotherapy in Anterior Cruciate Ligamentoplasty Pain: A Scoping Review.

Cryotherapy is used in individuals in the postoperative period (PO) of anterior cruciate ligament (ACL) repair, owing to its effects such as increased pain threshold, decreased cellular activity, and vasoconstriction. The aim of this study was to analyze the effect of cryotherapy on pain intensity in the immediate PO of ACL reconstruction. A scoping review was performed in the databases: Cochrane, Embase, Lilacs, LIVIVO, PEDro, PubMed, Scopus, and Web of Science; and gray literature: Google Scholar, CAPES Thesis Database, and Open Grey. PRISMA recommendation was followed. Two blinded reviewers performed the selection of studies: Phase 1-reading of titles and abstracts and Phase 2-Reading of the full texts and disagreements resolved in consensus. The references of 701 studies were identified, 603 from the main databases and 98 from the gray literature. After removal of duplicates, 387 studies were left for Phase 1-reading of titles and abstracts according to eligibility criteria and for Phase 2-28 studies for reading of full texts. Two studies were excluded: one randomized clinical trial and another sandwich study. Finally, 15 studies were included in this review. Cryotherapy is effective in reducing pain intensity because there were reductions in the scores of subjective pain scales in the immediate PO of ACL reconstruction. Cryocompression was shown to be superior to conventional cryotherapy.

Landing-Takeoff Asymmetries Applied to Running Mechanics: A New Perspective for Performance.

BACKGROUND: Elastic bouncing is a physio-mechanical model that can elucidate running behavior in different situations, including landing and takeoff patterns and the characteristics of the muscle-tendon units during stretch and recoil in running. An increase in running speed improves the body's elastic mechanisms. Although some measures of elastic bouncing are usually carried out, a general description of the elastic mechanism has not been explored in running performance. This study aimed to compare elastic bouncing parameters between the higher- and lower-performing athletes in a 3000 m test. METHODS: Thirty-eight endurance runners (men) were divided into two groups based on 3000 m performance: the high-performance group (Phigh; n = 19; age: 29 ± 5 years; mass: 72.9 ± 10 kg; stature: 177 ± 8 cm; 3000time: 656 ± 32 s) and the low-performance group (Plow; n = 19; age: 32 ± 6 years; mass: 73.9 ± 7 kg; stature: 175 ± 5 cm; 3000time: 751 ± 29 s). They performed three tests on different days: (i) 3000 m on a track; (ii) incremental running test; and (iii) a running biomechanical test on a treadmill at 13 different speeds from 8 to 20 km h-1. Performance was evaluated using the race time of the 3000 m test. The biomechanics variables included effective contact time (t ce), aerial time (t ae), positive work time (t push), negative work time (t break), step frequency (f step), and elastic system frequency (f sist), vertical displacement (S v) in t ce and t ae (S ce and S ae), vertical force, and vertical stiffness were evaluated in a biomechanical submaximal test on treadmill. RESULTS: The t ae, f sist, vertical force and stiffness were higher (p < 0.05) and t ce and f step were lower (p < 0.05) in Phigh, with no differences between groups in t push and t break. CONCLUSION: The elastic bouncing was optimized in runners of the best performance level, demonstrating a better use of elastic components.

[Possible changes in energy-minimizer mechanisms of locomotion due to chronic low back pain - a literature review]. / Possíveis alterações no mecanismo minimizador de energia da caminhada em decorrência da dor lombar crônica - revisão de literatura.

One goal of the locomotion is to move the body in the space at the most economical way possible. However, little is known about the mechanical and energetic aspects of locomotion that are affected by low back pain. And in case of occurring some damage, little is known about how the mechanical and energetic characteristics of the locomotion are manifested in functional activities, especially with respect to the energy-minimizer mechanisms during locomotion. This study aimed: a) to describe the main energy-minimizer mechanisms of locomotion; b) to check if there are signs of damage on the mechanical and energetic characteristics of the locomotion due to chronic low back pain (CLBP) which may endanger the energy-minimizer mechanisms. This study is characterized as a narrative literature review. The main theory that explains the minimization of energy expenditure during the locomotion is the inverted pendulum mechanism, by which the energy-minimizer mechanism converts kinetic energy into potential energy of the center of mass and vice-versa during the step. This mechanism is strongly influenced by spatio-temporal gait (locomotion) parameters such as step length and preferred walking speed, which, in turn, may be severely altered in patients with chronic low back pain. However, much remains to be understood about the effects of chronic low back pain on the individual's ability to practice an economic locomotion, because functional impairment may compromise the mechanical and energetic characteristics of this type of gait, making it more costly. Thus, there are indications that such changes may compromise the functional energy-minimizer mechanisms.

Comparison of static postural balance between healthy subjects and those with low back pain.

OBJECTIVE: To compare the static postural balance between women suffering from chronic low back pain and healthy subjects, by moving the center of pressure. METHODS: The study included 15 women with low back pain (LBP group) and 15 healthy women (healthy group). They were instructed to remain in standing on the force platform for 30 seconds. We analyzed the area and the speed of displacement of center of pressure of both groups. Data analysis was performed using the Student's t-test, with significance of 5%. RESULTS: Individuals with chronic low back pain showed a larger area of displacement of the center of pressure relative to the healthy ones but there was no significant difference in the speed of displacement of the center of pressure. CONCLUSION: Individuals with chronic low back pain had alterations in static balance with respect to healthy ones. Level of Evidence III, Prognostic Studies.