Lívia Pinheiro Carvalho

Effect of functional stabilization training on lower limb biomechanics in women.

PURPOSE This study aimed to verify the effects of functional stabilization training on lower limb kinematics, functional performance, and eccentric hip and knee torques. METHODS Twenty-eight women were divided into a training group (TG; n = 14), which carried out the functional stabilization training during 8 wk, and a control group (CG; n = 14), which carried out no physical training. The kinematic assessment of the lower limb was performed during a single-leg squat, and the functional performance was evaluated by way of the single-leg triple hop and the timed 6-m single-leg hop tests. The eccentric hip abductor, adductor, lateral rotator, medial rotator, and the knee flexor and extensor torques were measured using an isokinetic dynamometer. RESULTS After 8 wk, the TG significantly reduced the values for knee abduction (from -6.86° to 1.49°), pelvis depression (from -10.21° to -7.86°) and femur adduction (from 7.08° to 5.19°) as well as increasing the excursion of femur lateral rotation (from -0.55° to -3.67°). Similarly, the TG significantly increased the values of single-leg triple hop (from 3.52 to 3.92 m) and significantly decreased the values of timed 6-m single-leg hop tests (from 2.43 to 2.14 s). Finally, the TG significantly increased the eccentric hip abductor (from 1.31 to 1.45 N · m · kg(-1)), hip lateral rotator (from 0.75 to 0.91 N · m · kg(-1)), hip medial rotator (from 1.45 to 1.66 N · m · kg(-1)), knee flexor (from 1.43 to 1.55 N · m · kg(-1)), and knee extensor (from 3.46 to 4.40 N · m · kg(-1)) torques. CONCLUSIONS Strengthening of the hip abductor and lateral rotator muscles associated with functional training improves dynamic lower limb alignment and increases the strength and functional performance.

Prediction of Cardiorespiratory Fitness by the Six-Minute Step Test and Its Association with Muscle Strength and Power in Sedentary Obese and Lean Young Women: A Cross-Sectional Study

Impaired cardiorespiratory fitness (CRF) is a hallmark characteristic in obese and lean sedentary young women. Peak oxygen consumption (VO2peak) prediction from the six-minute step test (6MST) has not been established for sedentary females. It is recognized that lower-limb muscle strength and power play a key role during functional activities. The aim of this study was to investigate cardiorespiratory responses during the 6MST and CPX and to develop a predictive equation to estimate VO2peak in both lean and obese subjects. Additionally we aim to investigate how muscle function impacts functional performance. Lean (LN = 13) and obese (OB = 18) women, aged 20–45, underwent a CPX, two 6MSTs, and isokinetic and isometric knee extensor strength and power evaluations. Regression analysis assessed the ability to predict VO2peak from the 6MST, age and body mass index (BMI). CPX and 6MST main outcomes were compared between LN and OB and correlated with strength and power variables. CRF, functional capacity, and muscle strength and power were lower in the OB compared to LN (<0.05). During the 6MST, LN and OB reached ~90% of predicted maximal heart rate and ~80% of the VO2peak obtained during CPX. BMI, age and number of step cycles (NSC) explained 83% of the total variance in VO2peak. Moderate to strong correlations between VO2peak at CPX and VO2peak at 6MST (r = 0.86), VO2peak at CPX and NSC (r = 0.80), as well as between VO2peak, NSC and muscle strength and power variables were found (p<0.05). These findings indicate the 6MST, BMI and age accurately predict VO2peak in both lean and obese young sedentary women. Muscle strength and power were related to measures of aerobic and functional performance.

Diferenças biomecânicas entre os gêneros e sua importância nas lesões do joelho

INTRODUCTION: Several studies have been carried out to determine the biomechanical factors responsible by the greater incidence of patellofemoral pain syndrome and anterior cruciate ligament injury in women, when compared to men. OBJECTIVE: The aim of this study was to perform a non-systematic review of the literature of the biomechanical differences between genders, especially those concerning to the hip joint, related to the higher incidence of knee injuries in women, and verify its implications for developing preventive strategies. METHODOLOGY: Articles published between 1985 and 2008 were selected by two independent reviewers of the follow data bases: LILACS, MEDLINE, Cocharane and PubMed. It was selected theoretical, transversal, and correlational studies as well as controlled clinical trial with experimental designs well defined. RESULTS AND DISCUSSION: The studies selected showed that women perform functional activities with lower angles of knee and hip flexion, as well as greater knee valgus, hip adduction and medial rotation. Furthermore, it is believed that the differences shown in the coronal and transverse planes of the hip are more significant for the development of injuries in women than those occurred only in the sagittal plane. Finally, the studies show that neuromuscular training carried out preventively improves the dynamic alignment of the lower limb in women, reducing the incidence of knee injuries on them. CONCLUSION: There are evidences that women have biomechanics differences of the lower limb movement pattern when compared to men that may contribute for the greater incidence of knee injuries observed in women.

Metabolic syndrome impact on cardiac autonomic modulation and exercise capacity in obese adults

Obesity is often associated with increased risk of cardiometabolic morbidities and mortality. However, evidence shows that some obese individuals are more likely to develop such risk factors early in life, including those with Metabolic Syndrome (MetS). Whether the presence of MetS in obese people impairs cardiac autonomic modulation (CAM) remains to be investigated. METHODS Cross-sectional study. Sixty-six subjects were classified as normal-weight (NW, n = 24) or obese (BMI ≥ 30 kg·m-2): metabolically healthy (MHO, n = 19) vs unhealthy (MUHO, n = 23: NCEP/ATPIII-MetS criteria). Body composition (bioimpedance), metabolic (glucose-insulin/lipid) and inflammatory profiles were determined. Linear and nonlinear heart rate variability (HRV) indices were computed at rest and during the submaximal six-minute step test (6MST). Blood pressure (BP) and metabolic and ventilatory variables were assessed (oxygen uptake, VO2; carbon dioxide production, VCO2; minute ventilation, VE) during the 6MST and the maximal cardiopulmonary exercise testing (CPX). RESULTS All groups reached the same 6MST intensity (VO2 ~ 80% and HR ~ 87% of CPX peak values). Both obese groups, independently of MetS, presented higher BP and lower maximal VO2 than NW. However, HRV differed between groups according to MetS at rest and during exercise: MUHO had lower meanRRi and SD1 than NW and lower RMSSD and pNN50 than MHO at rest; during exercise, the lowest SDNN, TINN, SD1 and Shannon entropy were observed for MUHO. Significant correlations were found between MetS, insulin resistance and HRV indices; and between insulin resistance and aerobic capacity (VO2peak). CONCLUSION Obesity per se impairs aerobic-hemodynamic responses to exercise. However, MetS in obese young adults negatively impacts overall HRV, parasympathetic activity and HRV complexity.

Myostatin and adipokines: The role of the metabolically unhealthy obese phenotype in muscle function and aerobic capacity in young adults

HighlightsMyostatin is related to Metabolic Syndrome, hypertrophy and inflammation in humans.Adipokines are related to body fatness and aerobic capacity.Myostatin and adipokines are not associated with energy expenditure and muscle function.Myostatin and adipokines cutoffs can identify metabolically unhealthy obesity. &NA; Obesity is often associated with metabolic disorders. However, some obese people can present a metabolically healthy phenotype, despite having excessive body fat. Obesity‐related cytokines, such as myostatin (MSTN), leptin (LP) and adiponectin (ADP) appear to be key factors for the regulation of muscle and energy metabolism. Our aim was to compare lipid, glucose‐insulin and inflammatory (tumor necrosis factor alpha; TNF‐&agr;) profiles, muscle function, energy expenditure and aerobic capacity between healthy normal‐weight (NW) adults, metabolically healthy obese (MHO) and metabolically unhealthy obese (MUHO) adults; to study the associations between these outcomes and the cytokines MSTN, ADP, LP; and to establish cutoffs for MSTN and LP/ADP to identify the MUHO phenotype. Sixty‐one young adults (NW, n = 24; MHO, n = 16; MUHO, n = 21) underwent body composition (body fat ‐BF and muscle mass ‐ MM), energy expenditure at rest (RER) and aerobic capacity (VO2peak) evaluation, muscle strength and endurance tests and blood profile characterization (glucose‐insulin homeostasis and serum MSTN, ADP, LP and TNF‐&agr;). MHO and MUHO had a BMI ≥ 30 kg m−2. MUHO was defined as presenting ≥3 criteria for metabolic syndrome (NCEP/ATPIII) in association with insulin resistance (HOMA‐IR ≥3.46). MSTN and LP/ADP were associated with MM, MetS and glucose‐insulin profile; MSTN was associated with TNF‐&agr; and only LP/ADP was associated with parameters of obesity and VO2peak. Neither MSTN nor LP/ADP was associated with muscle functions (p < .05 for adjusted correlations). Both of them were able to discriminate the MUHO phenotype: MSTN [AUC(95%CI) = 0.71(0.55–0.86), MSTN > 517.3 pg/mL] and LP/ADP [AUC(95%CI) = 0.89(0.81–0.97), LP/ADP > 2.14 pg/ng]. In conclusion, high MSTN and LP/ADP are associated with MetS, glucose‐insulin homeostasis impairment and low muscle mass. Myostatin is associated with TNF‐&agr; and leptin‐to‐adiponectin ratio is associated with body fatness and aerobic capacity. Neither MSTN nor LP/ADP is associated with energy expenditure, muscle strength and endurance. Myostatin and adipokines cutoffs can identify the metabolically unhealthy obese phenotype in young adults with acceptable accuracy.

Are cardiovascular and metabolic responses to field walking tests interchangeable and obesity-dependent?

Abstract Purpose: To investigate if cardiovascular and metabolic responses to the six-minute walk test (6MWT) and incremental shuttle walking test (ISWT) are in agreement with cardiopulmonary exercise testing (CPX) and determine if both submaximal tests are interchangeable in obese and eutrophic individuals. Method: Observational and cross-sectional study included 51 obese women (ObG) and 21 controls (CG) (20–45 years old). Subjects underwent clinical evaluation, CPX, the 6MWT and ISWT. We applied Bland–Altman plots to assess agreement between walking tests and CPX. Correlation analysis assessed relationships between key variables. Results: There was an agreement between CPX and both the 6MWT [oxygen uptake (VO2 mL kg−1 min−1) = 6.9 (CI: 5.7–8.1), and heart rate (bpm) = 37.0 (CI: 33.3–40.7)] and ISWT [VO2 (mL kg−1 min−1) = 6.1 (CI: 4.9–7.3), and heart rate (bpm) = 36.2 (CI: 32.1–40.3)]. We found similar cardiovascular and metabolic responses to both tests in the ObG but not in the CG. Strong correlations were demonstrated between 6MWT and ISWT variables: VO2 ( r = 0.70); dyspnoea (r = 0.80); and leg fatigue (r = 0.70). Conclusions: 6MWT and ISWT may both hold interchangeable clinical value when contrasted with CPX in obese women and may be a viable alternative in the clinical setting when resources and staffing are limited. Implications for Rehabilitation Obesity is a worldwide epidemic, with high prevalence in women, and it is associated to impaired cardiorespiratory fitness and functional capacity as well as high mortality risk. Assessing oxygen uptake by means of cardiopulmonary exercise testing is the gold standard method for evaluating and stratifying cardiorespiratory fitness, however it is not ever applied due to costs and staffing. Walking field tests may be a cost-effective approach that provides valuable information regarding the functional capacity in agreement to metabolic and cardiovascular responses of cardiopulmonary exercise testing.

Comparison of diaphragmatic motion measured by M-mode sonography between different classes of obesity

Background: obesity can affect the respiratory system (RS) resulting in a lower tidal volume, decreased functional residual capacity, higher respiratory rate, low strength and endurance of the respiratory muscles and high levels of fatigue. However, little is known about the mobility of the diaphragm (MD) in this population. Aims : the aim of this study was to compare MD measured by M-mode ultrasonography between different classes of obesity. Methods : 20 obese (7 men/13 women) completed thestudy: 6 were classified as classII (45±11.3 years; BMI: 38.1±1.6 kg/m 2 ) and 14 as class III (41.4±7.1 years; BMI: 46.5±4.8 kg/m 2 ). Right MD was measured by ultrasonographic images by M-mode during quiet (QB) and deep breathing (DB). Results: Right MD during QB and DB were significantly (p Conclusion : morbidly obese negatively impact on MD. Strategies to increase MD and thus reduce RS alterations may be implemented in future studies. Supported by Capes/PNPD .