Michelle Cristina Sales Almeida Barbosa

The Pilates breathing technique increases the electromyographic amplitude level of the deep abdominal muscles in untrained people

OBJECTIVE To evaluate the behaviour of the upper rectus abdominis, lower rectus abdominis and transverse abdominis/internal oblique (TrA/IO) by using surface electromyography during trunk flexion with and without the Pilates breathing technique. METHODS Nineteen female subjects (without experience of the Pilates method) were recruited. The muscles were evaluated while trunk flexion was performed by using the Pilates breathing technique (POW) and Step Barrel device, followed by another contraction without the technique (NORM). Normality was accepted, and the paired t-test was used to determine data differences (p < 0.05). RESULTS Significant differences were noted in the amplitude level of activation between TrA/IO-POW and TrA/IO-NORM. The activation amplitude level of TrA/IO-POW significantly increased compared with all the other muscles under the NORM condition. CONCLUSION The breathing technique of the Pilates method associated with trunk flexion increases TrA/IO electrical activity.

Increased Activation Amplitude Levels of Gluteus Medius in Women During Isometric and Dynamic Conditions Following a 4-week Protocol of Low-load Eccentric Exercises

BACKGROUND The dysfunction of gluteus medius (GMed) has been implicated in other musculoskeletal disorders including low back pain and lower limb injuries. The purpose of this study was to use a protocol involving low-load eccentric exercises to observe the effects on the three subdivisions of GMed activation through surface electromyography (sEMG) and digital dynamometry. METHODS Eleven female subjects having femoral instability participated in a 4-week protocol (three sessions per week/non-consecutive days). At each session, two low-load eccentric exercises (12% of maximal isometric voluntary contraction [MVIC]) in abduction, extension and external rotation were applied to the hip joint. The sEMG of the GMed subdivisions (anterior, mid and posterior) during a squat and MVIC were assessed. The digital dynamometry was also assessed during MVIC. Parametric paired t-test was used to compare the results before and after treatment with α = 0.05. RESULTS The results showed an increased sEMG activity of GMed (middle and posterior portions) during isometric voluntary contraction and squat after the protocol. No difference was noted to the anterior subdivision of GMed. Another finding was the significant difference to the dynamometry results, showing improvements to generate strength to the GMed as a whole muscle in abduction. CONCLUSION The 4-week exercise protocol was effective to increase the activation of the GMed middle and posterior subdivisions, improving also the capacity to generate strength as a whole muscle during the proposed tasks. Copyright

Immediate improvements in activation amplitude levels of the deep abdominal muscle following a sacroiliac joint manipulation during rapid upper limb movement

OBJECTIVE To assess the immediate effects on the electrical activity of the transversus abdominis/internal oblique (TrA/IO) muscle during rapid voluntary upper limb movements before and after a sacroiliac joint (SIJ) manipulation. METHODS Twenty healthy subjects who had innominate fixation, assessed by standing flexion test, were recruited. All subjects were submitted to SIJ manipulation and the TrA/IO muscles were evaluated bilaterally, before and after the procedure, through surface electromyography while ten random rapid upper limb flexions or abductions were performed. Normality was accepted, and the paired t-test was used to determine data differences (p < 0.05). The correlations were calculated using Pearson correlation coefficient. RESULTS All subjects presented an increase of SIJ mobility after manipulation (negative standing flexion test). Significant differences in muscle activation were noted to ipsi- and contralateral TrA/IO recruitment, prior to (A1) and after (A2) the manipulation. The A2 data were statistically greater than those in the A1. The Pearson coefficient revealed a strong correlation between the TrA/IO side and the increase in muscle activation amplitude level. Also, the data showed a moderate to strong correlation between this last variable and the moments of evaluation. CONCLUSION The SIJ manipulation immediately improved the electrical activity of the TrA/IO muscle during rapid voluntary upper limb movements, suggesting improved segment stability and an increment to the afferent stimuli in order to affect the motor response.

Pain, balance, grip strength and gait parameters of older adults with and without post-chikungunya chronic arthralgia

To compare the levels of pain, grip strength, balance and gait in older adults with and without post‐Chikungunya chronic arthralgia (PCCA).

Alternative acid-functional monomer and its pH influence on the enamel

Purpose: The aim of this study was to synthesize an alternative acidic monomer (polypropylene glycol phosphate methacrylate – Poly-P) to constitute experimental two-step self-etch adhesive systems and to evaluate its influence on the pH and microshear bond strength ( SBS) to enamel. Methods and materials: Four primers containing Poly-P (10, 15, 30 or 50wt%), 2-hydroxyethyl methacrylate (HEMA), ethanol, and water were prepared, which were allocated in two subgroups according to an adjusted (buffered) or non-adjusted (non-buffered) pH. One experimental control and one commercial (ClearfillTM SE Bond) references were used. SBS protocol was performed at human enamel, followed by mechanical testing (EMIC). Scanning Electron Microscopy (SEM) was performed after each primer application. Data was analyzed by One-Way Kruskall–Wallis and Student-Newman–Keuls tests (p<0.05) and by linear regression predictive models. Results: As greater the Poly-P content, the lower the primer’s pH. Buffered groups showed lower SBS values than non-buffered groups. Groups with Poly-P content equal or higher than 30wt% showed similar SBS results when compared to the controls. SEM images demonstrated that only primers with high Poly-P content (30 and 50wt%) etched enamel in a more evidenced Type 1 (prisms exposure) etching pattern. Conclusion: The pH of the primer was directly influenced by the concentration of acidic monomer, which directly affected the enamel bond strength results. Poly-P is a potential monomer to be used in the formulation of self-etch dental adhesive systems.

Eletromiografia do reto femoral e gastrocnêmio durante vibração de todo corpo e agachamento com e sem plantiflexão

Resumen pt: Objetivo: Comparar a atividade eletromiografica do reto femoral (RF) e gastrocnemio medial (GM), submetidos a vibracao corporal (VTC), ausencia de VTC e ...