Structured Physical Activity did not Affect the Body Fat Percentage among Gymnastics Studio Members

Erina Febriani Widiastari, Fatimah Eliana Taufik, Diniwati Mukhtar 1 Faculty of Medicine, YARSI University, Jalan Letjen. Suprapto Kav.13, Cempaka Putih, Central Jakarta, Jakarta, Indonesia. 2 Department of Internal Medicine, Faculty of Medicine, YARSI University, Jalan Letjen. Suprapto Kav.13, Cempaka Putih, Central Jakarta, Jakarta, Indonesia. 3 Department of Physiology, Faculty of Medicine, YARSI University, Jalan Letjen. Suprapto Kav.13, Cempaka Putih, Central Jakarta, Jakarta, Indonesia.


INTRODUCTION
Physical activity is known to play an important role in preventing obesity and the distribution of body fat. 1 Based on the research by Rachmi et al. in 2017, 2 Referring to the Basic Health Research (Riskesdas) data in 2007 and 2010, it showed that the prevalence of 19 to 55-year-old overweight or obese adults increased from 19.8% in 2007 to 23% in 2010, with the highest prevalence in women compared to men in the second year. One of the risk factors of obesity is a lack of physical activities. 2 The excess of body fat in organs can be associated with the risk of diseases such as diabetes, cardiovascular disease, and other metabolic diseases. 3 The decrease in visceral fat mass has a significant relationship with a risk reduction of coronary heart disease. 4 The proportion of the less significant physical activity, in general, is 26.1% based on the data from Basic Health Research (Riskedas) in 2013. The criteria for significant physical activity are individuals who perform heavy or moderate physical activity or both. Meanwhile, the criteria for less significant physical activity are individuals who do not carry out either moderate or substantial physical activity. The result showed an increase in the number of obese adults with the highest prevalence in women. One risk factor of obesity is a lack of physical activity. DKI Jakarta is one of the highest provinces with a population with less significant physical activity, with a total of 44.2%. 5 An exercise is an inexpensive activity, free from pharmacological elements, and is useful for the transformation of body composition and can reduce cardiometabolic risk. It is such a powerful strategy for fat reduction, especially abdominal visceral fat. 6 The recommended exercise program to improve physical fitness is CRIPE (continuous, rhythmical, interval, progressive, endurance). The 50 to 60-minute perpetual physical exercise was conducted rhythmically within a specified interval by gradually increasing weight training to improve the freshness and endurance of the cardiovascular system. 7 Several exercises that can be applied in daily life are such as aerobics, cycling, Zumba, modern dance, and so on. 8 Research conducted by Irving et al. in 2018, 6 showed that physical activity is effective in reducing body fat percentage, fat mass, waist circumference, and abdominal circumference in obese adults. it is interesting to research the effect of structured physical activity on the decrease in the percentage of body fat in gym members.

MATERIALS AND METHOD
This research is an experimental study with one group pretest-posttest design. This research was conducted by giving treatment in the form of physical activity in one group of respondents without a control group for three months. Measurement of the respondent's body fat percentage was carried out within pre and posttreatment. The population and sample were members of the R and K gymnastics studios in Cempaka Putih and Johar Baru, in November 2017 until January 2018.
The inclusion criteria in this study included members of the gymnastics studio who were 18-60 years old. Meanwhile, the exclusion criteria were those who were not willing to take part in this study for three months and were pregnant. Then, the sample was selected using nonprobability sampling, namely purposive sampling, and then 36 respondents were obtained while 11 respondents dropped out. Data collection was carried out by conducting interview and observation to record the frequency of respondents' physical activity as well as the habits of the respondents such as a diet program, Monday-Thursday fasting habits, and exercise habits other than the one examined in this study and physical examination of body weighing to identify the percentage of body fat in the beginning and the end of the study. The method of body weighing was conducted in a way that the respondent was barefoot, looked straight ahead, with the position of the hand holding one part of the weighing tool, and stood upon the weighing tool until it showed the body fat percentage automatically. Bivariate analysis in this study used a paired t-test.

RESULT
This research was conducted on two groups of females at the R gymnastics studio in Cempaka Putih and K gymnastics in Johar Baru, with a total of 36 respondents. The respondents carried out a structured physical activity such as aerobics for at least 150 minutes per week for 12 weeks. During the study, four people resigned, and seven people did not fit the inclusion criteria and that the number of samples that could be monitored for three months was 25 people. Measurements were taken twice at the beginning and the end of the twelfth week. Table 1 showed the respondents' characteristic. Table 2 showed the results of body fat percentage at pre and post treatment and Table 3 showed the T-test analysis result.  Based on the results in Table 1, it showed that by the age, more than half respondents were early adulthood (52%) and classified as obese (52%). Furthermore, Table 2 showed that even an increase in the number of respondents who experienced overweight among respondent age 20-40 years old, from 3 to 4. The T-test analysis that shown in Table  3 revealed the value of p=0.357 (p>0.05).

DISCUSSION
Referring to Asian BMI criteria such as normal BMI of 18.5 to 22.9 kg/m 2 , overweight 23-24.9 kg/m 2 , and obese ≥25 kg/m 2 . 9 The result showed that the respondents were female with a normal BMI category of 24%, overweight by 24%, and obese by 52%. In numeral, it revealed a decrease in body fat percentage of 13 people in which three people did not change, and nine people experienced an increase in body fat percentage. Yet, based on the classification on Table 2, there is no change in each classification except in overweight age 20-40 years actually increased from 3 to 4. In the group of respondents who intensively underwent the physical activity examined in the study, there is an average reduction in body fat percentage of 0.236%. This decrease was not statistically significant since the result of the bivariate analysis with paired t-test showed P = 0.357, indicating that there was no influence between structured physical activity on the de body fat percentage.
The percentage of body fat can be influenced by various factors, such as food intake. The study of Lombardo et al., (2017) 10 suggested that calorie restriction and exercise can reduce the percentage of fat mass. Dietary (food) interventions, in general, can produce a greater energy deficit, and it can accelerate the decrease in body mass rather than only carrying out the exercise without any dietary interventions. 11 In contrast, a study found that aerobic exercise three times per week with a hypocaloric diet for changes in body composition revealing that there were no significant differences in fat mass between the group who consumed food before conducting the exercise and the group who did not. 12 Another study stated that conducting an aerobic exercise for 12 weeks showed a decrease in fat mass of 1.3 kg and a percentage decrease of 1% in the moderate exercise respondent group without dietary intervention. The result indicates that there is no significant effect on fat mass reduction and body fat percentage. The decrease that occurred in the exercise group was not as significant as the diet group or the combination of diet and exercise group. 13 In another study of the effects of diet and aerobic exercise for 12 months by comparing the exercise group, the diet group, the combination of exercise and diet group, as well as the control group. 11 The result of this study showed that the combination of diet and exercise group and the diet group have a higher percentage of body fat reduction than the exercise group. 14 It suggested that diet and exercise interventions for eight weeks decreased body mass index, and increased physical fitness level. However, no significant effect was found on body fat, and diet intake was the most influential variable. 1 It explains why this study did not show a significant reduction in body fat percentage. It is because one of the factors affecting the body fat was diet and food intake controls, which were not carried out in this study.
Based on the result of the interview, all respondents did not have a significant difference in the diet condition. Rice and side dishes such as  | 13 chicken, eggs, vegetables, and fruit become their daily food. However, the frequency and portion of the food are undoubtedly different from one person to another. Half of the total respondents who experienced a decrease in body fat percentage often underwent Monday-Thursday fasting every week.
In the group that experiences an increase in body fat percentage, most respondents did not undergo Monday-Thursday fasting and were identified to consume food after the exercise frequently. In this case, fasting plays an important role since, during the fasting activity, our bodies absorb energy sources from fatty acids produced by adipocytes to reduce the percentage of body fat. 15 Furthermore, another factor is physical activity. Physical activity is associated with a lower BMI and a low percentage of body fat. Thus, the higher the level of physical activity is, the lower the percentage of body fat will be. 16 Based on the result of the interview, the group that experienced a decrease in the body fat percentage included workers, housewives, and students. They had more physical activities in their daily life than other respondents, such as playing basketball, doing yoga, and doing gymnastics in the studio more than 150 minutes a week.
The group that experienced an increase in the body fat percentage has a profession as housewives who did not carry out other physical activities outside of 150-minute gymnastics in the studio. It indicates that there are differences in the result of the body fat percentage at the beginning and the end of the study due to the different daily physical activities other than aerobics among the respondents. The researchers were unable to limit the daily activities carried out by the respondents during the research. Another limitation of the study is the limited sample due to various unavoidable factors from respondents, such as illness or longdistance traveling during the data collection process of the study.

CONCLUSION
Structured physical activity has no significant effect on reducing body fat percentage among gymnastics studio members.