A Randomized Controlled Trial on Impacts of Exercise on Weight Management among Women with Abdominal Obesity

Abnormal obesity and its causes

Abnormal obesity is a common topic in the contemporary world owing to the increased incidences of obesity cases. There are many causes of obesity including physical inactivity, lifestyle, and diet among others and is categorized as a health risk having been proven to be associated with diseases. For example, studies have indicated a relationship between coronary heart disease and mortality, subclinical and carotid atherosclerosis and aortic stiffness among other conditions. Women have a higher risk exposure to CHD which is associated with increased waist circumference making it critical to define potential remedies to the problem in women (Choo et al. 82).

Literature Review

Physical exercise and diet interventions are applied in weight management strategies and in reducing CHD risk exposure in obese persons. When administered alone, exercise intervention has been proven to cause less effect as compared to when both the exercise and diet intervention are applied concurrently. However, there are different forms of exercises including resistance and aerobic exercises aid in improving carotid intima-media thickness, aortic stiffness, endothelial dysfunction, and subclinical atherosclerosis. Aerobic and resistance exercise mix is more effective in improving conditions like cardiometabolic and anthropometric profiles than either aerobic or resistance models applied alone. The variation in the impact of various forms of exercise is influenced by the different levels of pressure on arterial and endothelial walls that influence the patterns of blood flow. Other than facilitating a decrease in waist circumference and body weight, combination exercises also affect sugar control in persons with type 2-diabetes. However, there exists a research gap in whether the three types of exercises have varying effects on subclinical atherosclerosis markers (Choo et al. 82).

Methods

Participants

The research was conducted in an urban setting in South Korea where approximately 490,000 residents were recruited. The recruitment process was carried out by use of mass mailing advertisements, poster leaflets, and telephone. Eligible candidates were screened, and the successful asked for consent. Eligibility criteria included:

1. Persons of female gender aged 18-65 years

2. Waist perimeter greater than or equal to 185 centimeters

3. Willingness to be assigned an exercise model

The candidates with the following characteristics were excluded in the list of participants.

1. Health conditions like diabetes, cancers or cardiovascular diseases

2. Current use of hormone therapy

3. Physical limiting factors to exercise ability

4. Weight loss intervention participation within the last one year

5. Weight change within four weeks before the study.

Upon signing an informed consent by the qualified participants and approval by the Korea University institutional review board, data on waist perimeter and body mass index (BMI), fasting glucose and body lipids were obtained by use of questionnaires (Choo et al. 82).

Study design

The randomized trial was conducted for 12 months. The study participants were split into three groups; resistance, aerobic and combined training groups (Choo et al. 82).

Intervention

Two different interventions were conducted; diet-plus exercise and diet-alone interventions.

Measurement

The main result of the randomized trial was Flow-Mediated Dilation (FMD) while secondary outcomes were ’carotid-femoral pulse wave velocity’ (PWV) improvement and carotid intima-media thickness (IMT), anthropometric profile, cardiometabolic profile, and cardiorespiratory fitness. All the measures were assessed at quarter, half and one-year baseline. Weight measurement was conducted after an overnight of fasting where participants were required to wear a light outfit and be barefoot when being weighed. The waist circumference was computed in centimeters (Cm), BMI as weight (Kg)/height (M) 2. Samples of blood were also drawn in the morning before the participant could access food or any form of medication and the cholesterol, triglycerides, and glucose levels were determined and recorded. Brachial artery dilation was also established, and femoral PWV and carotid values deliver to measure arterial stiffness. Cardiorespiratory fitness was also conducted upon exposure to a one-mile walk test (Choo et al. 82).

Results

After a statistical analysis, the mean age of the participants was found to be 43.1 years while the average BMI was 28.5kg/m2. The average waist circumference of the participants was 94.8cm, 24.5% of the participants exhibited obesity relate conditions, and 29.1% had reached menopause (Choo et al. 82).

Discussion

The mode of exercise did not result in a substantial differential effect on IMT, PWV, and FMD for the 12 months study period in the mix of diet and exercise intervention. However, a differential effect was observed on glucose levels during fasting where combined exercise model was more effective than aerobic-based exercise in reducing the levels. The diet-exercise mix intervention exhibited significant time effects. There was neither differential time effect diet plus exercise nor effect of exercise modes on FMD of abdominal obese women.

Previous studies have informed the beneficial impact of both resistance and aerobic exercise FMD. Other researchers identified that the exercise models exert adverse outcomes, especially among children. Some studies have also shown that both combined and resistance training may effectively improve endothelial function prompting further research. The variation in the Choo et al. can be described by the multifaceted effects of diet and exercise in the study design (82). Choo et al. also found out that the differential impact on aortic PWV by exercise mode is insignificant (82). However, the diet-exercise mix intervention led to a substantial reduction in Aortic PWV confirming previous studies. However, there are a few studies that have indicated a negative correlation.

Exercise modes were found to have no significant impact on Carotid IMT, but a considerable regression of diet-plus-exercise intervention with Carotid IMT was discovered. The regression effect on carotid IMT by exercise training was non-linear over time. The peak attained at six months was not maintained to 12 months. There was insignificant proof of the benefit of either sole diet or diet together with exercise intervention on carotid IMT among obese and overweight persons. Being a measure of structure-based change in carotid arteries, carotid IMT may require long-term intervention programs prompting further clarification of the carotid IMT changes in the short-term with the diet-exercise mix intervention. However, Choo et al. speculate that the changes emanate from various changes associated with cardiometabolic risk factors that are concurrent with the loss of weight by a mix of diet and exercise intervention. The study discovered a significant disparity effect of mode of exercise particularly a combination of resistance and aerobic exercise models on the level of fasting glucose but not on IMT, PWV, and FMD.

Conclusion

This study by Choo et al. is the only available study on the effect of exercise models in the management of weight intervention on dominant signs of subclinical atherosclerosis like arterial stiffness, carotid IMT, and endothelial dysfunction. The limitations of the study include; over the 12 months, the attrition rate was 55% alluding a possibility of bias that would have led to the invalidity of the results. 68% of the modified ITT study participants had a menstrual cycle and thus changes in hormonal imbalances. However, the effect of menstruation on vascular measurement was not considered during the study leading to an overestimation or overestimation of the changes in FMD. Another limitation of the study is that it cannot be generalized for the global population since it only explored women from Korea only Choo et al. 82). In conclusion, abnormally obese women can benefit higher benefits through the application of a combination of resistance and aerobic exercise for effective glucose control rather than a single mode. Regardless of the method of exercise, a combination of diet and practice intervention may be useful in reducing cardiometabolic risk and subclinical atherosclerosis in abdominally obese women.

Personal Opinion

I am of the opinion that obesity is a lifestyle condition and diet and exercise would contribute to a reduction of the body weight. However, the exercise should not be a one-year event but a continuous process preferably throughout a person’s life. Physical exercise induces sweating; a process that ensures that excessive water is expelled from the body cells. Sweating also removes harmful wastes from the body cells allowing for body processes to take place. A majority of people come from developed countries and urban areas where people are involved in limited body activity. The phenomena is not a coincidence but because people from rural areas are more physically active than city dwellers. I, therefore, believe that exercise would help in controlling obesity and the associated health issues. Foods also contribute to obesity, many of the obese people. Junk foods are proven to be causative agents of abnormal body weight.

Work cited

Choo, Jina, et al. “Effects of weight management by exercise modes on markers of subclinical atherosclerosis and cardiometabolic profile among women with abdominal obesity: a randomized controlled trial.” BMC cardiovascular disorders14.1 (2014): 82.