The influence of net ground reaction force orientation on mediolateral stability during walking.

BACKGROUND: Previous work has linked the eccentricity of the net ground reaction force (GRFnet) to increased mediolateral instability during single-step voluntary and compensatory stepping responses. The present work sought to understand the extent to which such control mechanisms for mediolateral stability are present during gait. RESEARCH QUESTION: How do gait velocity and step width constraints influence the kinetic control of mediolateral stability control among healthy participants? METHODS: 25 participants performed three walking conditions - normal walking with self-selected speed and foot-placement, fast walking with self-selected foot-placement, and narrowbase walking - across a 10-meter walkway. Lateral instability was quantified by the mediolateral margin of stability (MoSML). The frontal-plane eccentricity of the GRFnet was calculated as the difference between GRFnet vector orientation and that of a line joining the coordinates of COPnet and COM. Two discrete time-points (P1 and P2) following foot-contact were examined, as they have been suggested to be indicative of proactive and reactive COM control, respectively. Task-related differences in the magnitude and timing of kinematic and kinetic outcome variables were analysed using one-way ANOVAs with repeated-measures. RESULTS: With constraints on step-width in narrow-base walking, participants exhibited reduced stability as evidenced by reduced MoSML, alongside reductions in the peak GRFnet eccentricity (θd) at P1. Participants exhibited no reduction in stability during fast walking, as revealed by the MoSML in part because of a similar onset of P1 within the gait cycle. P2 magnitude was larger in narrow-base walking relative to fast-walking, and occurred at an earlier point in the gait cycle. SIGNIFICANCE: Findings suggest proactive mechanisms (i.e. P1) may predominantly regulate mediolateral stability during walking. Reactive mechanisms (i.e. P2), however, may be capable of offsetting instability in situations where proactive mechanisms are insufficient.

Assessment of obesity, overweight and its association with the fast food consumption in medical students.

INTRODUCTION: Obesity is a condition in which excess body fat accumulates, which leads to various adverse effects on health, particularly cardiovascular diseases (CVDs), which reduce life expectancy and/or increase health problems. Fast food consumption is one of the factors which have been reported as a cause of obesity. Body mass index (BMI) is used to assess obesity and overweight, which can be calculated by using the formula, weight in kg, divided by square of height in metres. AIM: This study focused on the relationship of body mass index with fast food consumption, associated soft drink consumption and physical activity. METHODS: Descriptive cross-sectional study was conducted in Department of Biochemistry, SBKS MI and RC, and Sumandeep Vidyapeeth. This study was approved by the ethical review board .One hundred and forty seven medical students from 1(st) year MBBS course were included in this study. Self-structured questionnaire was used, which contained several data like information on age, height, weight, education level. The formula used for calculating BMI was, weight in kg, divided by square of height in metres (Kg/m(2)). RESULTS: In our study, out of 147 students, a total of 138 students (more than 90%) used to have fast food. Among these, a total of 47 students (34.05%) were pre-obese and obese. Out of 147 students, 87 students (59.18%) were in normal weight range, while 13 (8.84%) students were underweight. STATISTICAL ANALYSIS: Data was compiled in an Excel worksheet and it was analyzed for percentages and proportions. Chi-square and Pearson's correlation test were also applied wherever they were applicable and Alpha error was set at a 5% level. CONCLUSION: In our study, a significant relationship was found between BMI and fast food consumption, less physical activity, and intake of soft drinks.