Introduction
High body weight, which is the result of increased body fat percentage due to inactivity, is associated with a variety of chronic diseases such as cardiovascular diseases, diabetes, cancer, and even death. Therefore, the use of appropriate strategies to reduce body weight and body fat percentage is of great importance. Exercise is one of the best ways for weight loss, which is done alone or in combination with a dietary regime. The use of supplements along with exercise can have more benefits. 
The positive effects of pomegranate are attributed to the high concentration of nitrate and polyphenolic compounds. Consumption of pomegranate extract along with endurance training can improve blood flow, increase resting metabolism, and reduce weight. However, the effect of its consumption along with resistance training on body composition and weight control has not been studied. In resistance training, the phosphagen system and anaerobic glycolysis have a greater contribution in energy production and the resources depleted during training are recycled at the time of resting. Therefore, it is possible that increased blood flow by consuming pomegranate extract can increase oxygen debt, a part of which is spent on phosphagen recycling and lactate excretion. On the other hand, the muscle protein synthesis is improved by delivering more essential amino acids to the muscle; consumption of pomegranate extract can help it by improving blood flow. Considering this hypothesis, this study aims to investigate the effect of 8 weeks of resistance training with pomegranate extract supplementation on resting metabolic rate, hypertrophy, and muscle strength of inactive male college students. 
Methods 
In this quasi-experimental study, 42 inactive male college students participated voluntarily after signing a written informed consent from. They were randomly divided into four groups: resistance training (n=11), resistance training + supplementation (n=11), supplementation (n=10) and control (n=10). The resistance training program was performed for 8 weeks, three sessions per week and included two movements for the upper body (barbell chest press and barbell shoulder press) and two movements for the lower body (leg extension and leg press with machine). The subjects in the resistance training + supplementation group and the supplementation group consumed 100 mL of pomegranate extract half an hour before the start of training sessions, while the control group did not participate in training. Body fat percentage of the subjects was calculated by measuring the thickness of subcutaneous fat in chest, abdomen and hip using a Caliper (LB RH159 Harpenden Skinfold, England) with an accuracy of 0.2 mm and based on Jackson & Pollock equation. For measuring the muscular hypertrophy (hip circumference), the distance from the large prominent point of the femur to the medial epicondyle of the femur was measured in standing position. Then, the midpoint of this distance was determined. The hip circumference was measured horizontally from this point. The maximum strength in lower body muscles and resting metabolic rate were also measured. Data analysis was performed using one-way analysis of variance with least significant difference post hoc test and paired t-test considering a significance level of P≤0.05. 
Results 
The results showed that the rate of muscle hypertrophy (hip circumference) increased significantly after 8 weeks of resistance training alone and resistance training plus pomegranate supplementation, which was higher in the supplementation training + supplementation group (P=0.001). The maximum strength in lower body muscles also increased significantly after intervention in two groups of resistance training and resistance training + supplementation (P=0.001). Body fat percentage decreased significantly in the resistance training + supplementation group (P=0.03). The anti-obesity mechanism of pomegranate extract includes inhibition of pancreatic lipase enzyme activity, suppression and prevention of energy intake, and having antioxidant effects. Another possible reason for reduction of the body fat percentage is the increase in hormones. Elevated catecholamines especially epinephrine is an important feature of resistance training which causes lipolysis and is primarily responsible for the release of free fatty acids from adipose tissue. 
Discussion 
In the present study, no significant change in body fat percentage was observed in two groups of resistance training and pomegranate extract supplementation. The 8-week period might not be sufficient for the effect of training alone or pomegranate extract supplementation alone; perhaps a longer duration is needed. Moreover, no significant change was observed in resting metabolism of any study groups (P>0.05). An interesting result was that the amount of muscle hypertrophy was higher in the group that consumed pomegranate extract along with performing resistance training; as a result, the study hypothesis was confirmed. However, more laboratory studies are needed. According to the results of the present study, it can be concluded that the combination of resistance training with pomegranate extract supplementation increases the muscle strength and hypertrophy in young men.
Ethical Considerations
Compliance with ethical guidelines
This study was approved by the ethics committee of Ardabil University of Medical Sciences (Code: IR.ARUMS.REC.1398.054).
Funding
This article was extracted from a MA. thesis of first author in Department of Exercise Physiology, Faculty of Education and Phychology, University of Mohaghegh Ardabili, Ardabil.
Authors' contributions
All authors equally contributed to preparing this article.
Conflicts of interest
There is no conflict of interest.
Acknowledgements
The authors would like to thank the University of Mohaghegh Ardabili for the financial support and all students participated in the study for their cooperation.

 

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