جستجوی مقالات مرتبط با کلیدواژه « شاخص های چاقی » در نشریات گروه « پزشکی »

‎ Obesity and how fat is distributed in the body, especially in the middle part of the body, is a good predictor of future diseases, and exercise is one of the best non-pharmacological methods in the prevention and treatment of obesity. Therefore, the aim of this study was to determine the effect of de-training following plyometric exercises on obesity indices and physical fitness factors of male students. 

‎ In the present quasi-experimental study, 20 male students from Alborz University physical education students were selected voluntarily and studied in 2 groups of plyometric training 10 people and control group 10 people (homogenized based on body mass index). To collect data, a demographic questionnaire, to evaluate the aerobic power of "Astrand Test", to evaluate the anaerobic power of "Sergeant Jump Test" and to measure the percentage of fat by "Jackson and Pollock Skinfold Test" were used. Also, the subjects' body mass index was measured by dividing weight by height squared (m) and (waist-hip ratio) by dividing waist circumference by pelvic circumference. After evaluating and recording the initial data of the subjects in the intervention group, plyometric exercises were performed for 6 weeks and the post-test data were recorded in the same conditions as the pre-test and after the end of the training period. After evaluating and recording the initial data of the subjects, the intervention group performed plyometric training for 6 weeks, including 3 and 4 sessions per week with one day in between. In the same conditions as the pre-test, the data related to the test phase and after 6 weeks data related to the post-test phase were recorded. Data analysis was performed in SPSS. 23.

Findings showed a significant effect of performing plyometric training for 6 weeks on aerobic (34.67±2.43_39.58±2.58‎) and anaerobic capacity (104.23±8.07_132.25 ±6.49‎), waist to hip ratio (0.84±0.17 _ 0.91±0.13‎), body fat percentage (14.54±2.18_11.49 ±2.75‎) and body mass index (23.01±1.68_ 20.08±1.93‎) in plyometric group (P<0.05). However, after 6 weeks of de-training, almost all training achievements for the subjects in the training intervention group disappeared, which indicates the principle of long-term training in performing plyometric training.

Findings confirmed the effect of plyometric training on cardiorespiratory function (significant increase in aerobic capacity) as well as improving health indicators. Therefore, due to the principle of diversity in training and the ease of using the gradual overload process in performing plyometric training (due to the nature of plyometric training), plyometric training in the field of health is recommended as an alternative training method for continuous aerobic training. However, it should be noted that the gains of plyometric training will disappear after a period of non-training.

 According to the World Health Organization, cardiovascular diseases account for approximately 30% of deaths worldwide. Obesity is one of the most important risk factors for developing cardiovascular diseases and other non-communicable diseases. Excessive obesity plays an important role in the development of cardiovascular risk factors such as hypertension, dyslipidemia, and diabete. Currently, body mass index and waist circumference are recommended for classification of overweight and obesity . Increased body mass index and waist circumference have been shown as a risk factor for cardiovascular disease . However, studies have shown that the discriminative capacity of BMI is questionable due to the inability to distinguish between adipose tissue and lean mass. This issue has led to the idea that by combining traditional anthropometric indices (such as height, weight, body mass index or waist circumference), a better physical index can be designed that considers and examines body shape Recently, Body Shape Index (BSI) has been proposed as a new body index. Krakower et al. (2012) reported a significant correlation between body shape index and visceral fat tissue and showed that premature deaths are more related to this index than waist circumference and body mass index. Body Roundness Index (BRI=BRI) is another new index proposed that based on waist circumference and height, can better predict the percentage of body fat and visceral fat compared to the traditional indices of body mass and circumference. Recently, several studies have shown that body circumference index can be used as an index of obesity to determine the presence of left ventricular hypertrophy, hyperthermia, cardiovascular disease and diabetes .The purpose of this study was to predict the relationship between physical activity and some new and traditional obesity indicators in women with cardiovascular disease and to determine the power of these indicators in the diagnosis of cardiovascular diseases.

This descriptive-correlation study was conducted on 334 women with CVD (middle: n=189, elderly: n=145) referring to a heart centers in Mashhad. The inclusion criteria included female patients in the age range of 40 to 75 years, myocardial infarction, heart attack, high blood pressure and cholesterol, and willingness to participate in the research. Cardiovascular disease factors were diagnosed by consulting a specialist doctor and reviewing medical records for each patient. To investigate the relationship between different factors, the study was conducted in different age groups. For this purpose, the subjects were divided into two groups: middle-aged (40-55 years, 189 people) and elderly (60-75 years, 145 people). Written informed consent was obtained from all study participants. The convenience sampling method was used. Physical activity level was measured with International Physical Activity Questionnaire (IPAQ). The body shape index (BSI), body roundness index (BRI), Waist circumference (WC), body mass index (BMI), Waist-Hip Ratio (WHR), fat mass percentage (%FM) were measured and calculated. Body shape index was calculated based on height (meters), body mass index and waist circumference (meters) using the formula. Body circumference index is based on height (meters) and waist circumference (meters). First, the irregularity (non-dimensional value) of the body (€) was determined using the formula. Irregularity measures the degree of ovality or roundness and ranges from zero (full circle) to one (vertical line).
Independent t test was used for show difference between middle age and elderly groups. To evaluate the possible correlations between obesity indices, Pearson and Spearman correlation coefficients were used. The Receiver operating characteristic (ROC) curve was used to determine the sensitivity and specificity and the best cut-off point of anthropometric indices.

The results showed that there is no significant difference for physical activity, body mass index, body roundness index, body shape index, waist circumference, waist-to-thigh ratio and body fat percentage between middle-aged and elderly groups. The results of the correlation coefficient showed that in both middle-aged and elderly groups, body roundness index has a positive relationship with waist circumference, body mass index, waist-to-thigh ratio and fat mass. In middle-aged people, the level of physical activity had no significant relationship with any of the variables, but in elderly patients, the level of physical activity had a negative relationship with body roundness index and body shape index. In the middle-aged group, the body roundness index had the largest area under the curve, and the body shape indices and waist-to-hip ratio are in the second place with a small difference. In the elderly, the waist circumference had the largest area under the curve and the body roundness index ranked second. The level of physical activity in both groups had the lowest area under the curve. The values ​​of the cut points using the highest sensitivity and the lowest specificity in the middle-aged group for the physical activity level is greater than 984.5, body roundness index is less than 5.41, body shape index is less than 0.0834, waist circumference is less than 89.7, Body mass index less than 26.3, body fat percentage less than 31.8 and waist to hip ratio less than 0.91 and in the elderly group, physical activity level more than 789.7, body roundness index less than 5.8, index Body shape was less than 0.0865, waist circumference was less than 91.5, body mass index was less than 28.03, body fat percentage was less than 30.46 and waist to hip ratio was less than 0.9.

Contrary to the initial hypothesis of the researchers, the research findings showed that the level of physical activity had the least ability to predict the presence of cardiovascular disease. According to the present research, there was a weak relationship between the level of physical activity and obesity indicators. Considering that prospective studies in adults have shown that low physical activity is closely related to the development of cardiovascular disease, however, it may be that if the amount of physical activity is low, its changes are not very reliable and cannot be a good predictor for the factors Cardiovascular risk. The level of physical activity in the present study was average (1135.7 meters/minute/week for the middle-aged group and 916.4 meters/minute/week for the elderly group) and the subjects were divided according to the International Physical Activity Questionnaire in terms of physical activity. According to Maisen et al.'s study (2011), the activity level is less than 600 met-minutes per week as inactive, between 600-1500 met-minutes per week as semi-active and more than 1500 met-minutes per week as active was considered. Among the possible reasons for the difference in the results of the mentioned studies, we can mention the physical fitness of the subjects, the disease and pathological conditions of the subjects, and gender. Body roundness index was created in order to predict body fat and visceral fat tissue percentage by using waist size in comparison with height, which makes it possible to estimate the body shape as an egg or oval. Body shape index independent of body size (height, weight and body mass index) creates a quantitative scale to estimate body shape. In preliminary studies, researchers have shown that BSI is a better predictor of premature mortality than BMI and WC in the general US population. According to the results of the study, BRI and WC are best indices for predicting the possibility of CVD in patient middle age and elderly women.

Aim. This study aimed to determine predictive power of obesity indices, cardiovascular fitness and physical activity in the development of cardiovascular disease (CVD) in male and female college students.
Background. Given the high mortality due to cardiovascular diseases from the young age caused by obesity and physical inactivity, the primary prevention, especially at an early age can be a solution to avoid the disease. Initial screening by simple, secure and affordable methods for prevention is essential.
Method. A total of 223 students (150 males, age 20.33±1.71 and 73 females, age 20.36±1.72) participated in this cross-sectional descriptive study. Data were obtained using a questionnaire, anthropometric measurements, and cardiovascular fitness (VO2max). Independent t-tests was used to show difference between gender in terms of variables, ANOVA was used to determine the differences among groups of male and female separately, whose had the different number of risk factors, and Pearson and Spearman correlation coefficient were used to determine the correlation of obesity indices and VO2max with metabolic risk factors, and the ROC curves was used to measure the power of predicting and the cut-off points of cardiovascular risk factors.
Findings.Statistically significant correlation was found between obesity indices and metabolic risk factors (other than blood glucose and systolic blood pressure in males). As the number of metabolic risk factors increased, elevation in obesity indices in females and the reduction of VO2max in males were significant. All obesity indices were within normal range. Cut-off points calculated by the ROC were 21.11 for body mass index and 75.15, 0.44 and 75.50, 0.47 for waist circumference and the waist-to-height ratio, for males and females respectively.
Conclusion. The findings of this study showed that the obesity indices are more powerful than physical activity levels and VO2max for predicting the possibility of cardiovascular disease among students.

TTo determine cutoff points of anthropometric variables for predicting incident cardiovascular disease in Iranian adults. In this cohort study, 1614 men and 2006 women, aged ≥ 40 years, participants of the Tehran Lipid and Glucose Study, who were free of cardiovascular disease at baseline, were followed for the mean of 7.6 years. Body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), waist to height ratio (WHtR) and cardiovascular risks were assessed. Incident cardiovascular disease was ascertained. The adjusted hazard ratios (HRs) for cardiovascular disease were calculated for one standard deviation (SD) change in all obesity variables using Cox proportional hazards regression analysis. Receiver operator characteristic (ROC) curve analysis was used as the method of defining the optimal point if each variable as a predictor of cardiovascular disease. We found 333 cardiovascular disease events during follow up. The risk factor adjusted HRs were significant for all anthropometric variables in males and waist to hip ratio in females and were 1.19, 1.24, 1.21 and 1.24 for body mass index, waist circumference, waist to hip ratio and waist to height ratio in males and 1.27 for waist to hip ratio in females, respectively (all P < 0.05). Receiver operator characteristic analysis showed the highest area under curve (AUC) for waist to hip ratio, waist to height ratio and waist circumference, followed by body mass index in males and both genders aged ≤ 60 years. In females, waist to hip ratio and waist to height ratio had the highest AUC, followed by waist circumference and body mass index. Among men and women > 60 years, all the anthropometric variables showed same cardiovascular disease predicting power. The optimal cut off values for cardiovascular disease prediction in males and females aged ≤ 60 years were; body mass indices 26.95 and 29.84 kg/m2, waist circumferences 94.5 and 90.5 cm, waist to hip ratios 0.95 and 0.89, and waist to height ratio 0.55 and 0.60, respectively. There was no difference between central obesity variables in predicting cardiovascular disease in males, whereas in females waist to hip ratio and waist to height ratio were more appropriate. The cutoff values of anthropometric variables were higher in the Iranian than other Asian populations.