4. Discussion

Within this study, we aimed to explore the relationship between physical activity and body composition among young females. The results showed expected correlation. Specifically, most results (SMM%, BFM%, VFA, FMI, FFMI) showed statistically relevant correlation (p > 0.001) with lifestyle variables, with lifestyle score being a somewhat stronger predictor in comparison to other variables.

This cross sectional study determined the existence of correlation between physical activity and certain parameters of body composition, as well as of the constructed mathematical model of body composition score for young women.

Our correspondents had normal (some say optimal) weight according to BMI (22.42 kg/m<sup>2</sup> ). A large scale sample (n = 1023) of female students of the University of Belgrade aged 21.3 years on average, average BMI was 20.7 kg/m<sup>2</sup> [50]. This difference could be explained by the fact that our correspondence are not only older by 3 years on average, but also by the fact that our sample includes working women, women who gave birth in addition to students, which can influence their health habits related to physical activity, nutrition, etc.

According to cutoffs % fat Heyward [51], young women from our research belong to the category of above average fat occurrence, which is unfavorable considering the likely increase in body fat during aging, especially related to the menopause [52]. Gába and Přidalová [53] applied the same method of measuring body composition among Czech women of the same age group (18–30 years). The correspondents had lower values of all variables that have fat component, that is, BM, BMI, %BFM, and VFA. There is a clear correlation between excess body fat, which is a basic characteristic of obesity and increased mortality among different ethnic groups around the world. Yet, it is clinically relevant that obesity is heterogeneous, and there are individual differences in regional fat distribution, especially in

Relation between Lifestyle and Body Composition among Young Females in Serbia of 18–29… DOI: http://dx.doi.org/10.5772/intechopen.83586

visceral adipose tissue [54]. There is a strong relation among visceral fats, metabolic syndrome, and the most common chronic non-infectious diseases of contemporary humans [55]. Enzi et al. [56] found that among lean or obese young women, subcutaneous abdominal fat dominates in relation to abdominal visceral fat, both measured by CT at the upper renal pole. There are no clearly defined standards for the visceral fat content. According to the measuring technique applied here, a VFA of 100 cm<sup>2</sup> [45] is considered as a risk, but this needs to be taken with caution as further studies are needed. Among our correspondents, the average value was 51.83 32.09 cm2 , while it was lover by 10 cm<sup>2</sup> in the study of Gába and Přidalová [53].

Fat-free mass index is the indicator indexed according to the body height (FFMI —kg/m<sup>2</sup> ) and is considered as not only a good indicator of the body composition of healthy, but also ill persons [57]. FFMI retains stable values among young and middle-aged women and men, and then drops after 74 years of age. Average FFMI value of our correspondents (16.45 1.35 kg/m<sup>2</sup> ) corresponded to the values obtained by the research of Kyle et al. [57] (14.6 and 16.8 kg/m<sup>2</sup> ) and belonged to the category of normal and high values. According to the these authors, BMI increase that comes with aging has been complemented with the increase in BF and FFM, and thereby with FFMI.

Fat-mass index (FMI) is significantly higher among sedentary than physically active men than women, and the difference rises with age [57]. Average FMI value of our correspondents (5.87 3.28 kg/m<sup>2</sup> ) corresponded to the values obtained by the research of Kyle et al. [57] (3.9–8.1 kg/m2 ) and belong to the category of normal.
