Submit Manuscript | http://medcraveonline.com Obesity defnation and measurment To most non-professionals, obesity means very fat and overweight means either less fat. Whereas overweight implied to excess body weight compared to set standards, obesity refers specifcally to having an abnormally high proportion of fat. 1 To health professionals and researchers, however, both these terms have defnitions that specify the degree of excess fat. 2 Body fat exists in storage and essential forms. Essential fat found in all organs involving the central nervous system or intestines that is necessary for body normal functions. Storage fat as an effcient energy fuel is accumulated in the adipose tissue, specially under the skin and that is affected by diet or exercise, whereas the amount of essential fat remains constant. 3 World health organization, in addition, produced a defnition of obesity based on Body Mass Index (BMI), as a criterion taking into particular consideration the correlation between this index and mortality and disability. 4 Indeed, body fatness assessed by BMI that is calculated by easily and quickly dividing an individual’s weight measured in kilograms by their height in meters squared (kg/m 2 ; e.g., a men weighing 80kg and measuring 1.7m, BMI=80/(1.7×1.7)=27.7kg/m 2 ). This index is independent of gender and age. 2 Table 1 shows accepted scale of BMI for degrees of overweight and obesity by WHO. 5,6 Defned objectively as a BMI of 30 or more, obesity is related with markedly increased health risks. Although, a BMI of 25kg/m 2 is the commonly accepted threshold for recognizing bedridden identifying a patient at higher risk for obesity- related illnesses. 7 Individuals who have a BMI of ≥have a 50-100% increased death hazard from all causes compared with individuals who have BMI 20- 25kg/m 2 . 8 Morbid obesity is defned by a BMI ≥40.0kg/m 2 . Body mass index calculation as a test for reorganization of overweight and obesity, although, is not a perfect measure, but it is the industry standard, as its formula makes it certainly accurate enough to determine presence of increased health hazard. 9,10 It, indeed, has replaced percentage ideal body weight as a criterion for assessing obesity for several reasons. 7 It is not proper index in individuals with a great muscle mass (such as bodybuilders) and falsely low in those that have lost muscle mass, such as the elderly. 11 The main assumption of BMI guidelines is that body mass, adjusted for stature squared, is closely associated with MOJ Womens Health. 2018;7(1):19‒24. 19 ©2018 Mehrabani et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Overweight and obesity: a brief challenge on prevalence, complications and physical activity among men and women Volume 7 Issue 1 - 2018 Javad Mehrabani, Zeynab Khazraei Ganjifar Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Guilan, Iran Correspondence: Javad Mehrabani, Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Guilan, P.O Box 1438, Rasht, Iran, Tel/Fax +98- 0131-6690675, Email mehrabanij@gmail.com Received: August 21, 2017 | Published: January 17, 2018 Abstract Obesity is a major problem for public health due to weight gain from imbalance between energy intake and energy expenditure. According to published data by World Health Organization (WHO), obesity was increased rapidly from outset of last decades of 1900. Prevalence of obesity is accepted as a socioeconomic challenge in present decade. Based on this topic, in particular since 1980 decade, if this trend cannot be reversed or at least restrained, high levels of obesity will naturally lead to increases in the prevalence of chronic diseases, with enormous economic and personal costs. Epidemiological reports show, in 2008, approximately 35% of adults were overweight (body mass index [BMI] ≥25-29.9kg/m2) (34% men and 35% of women). The worldwide obesity prevalence has increased meaningfully between 1980 and 2008. In 2008, 10% of men and 14% of women in the world were obese (BMI≥30kg/m2), compared with 5% for men and 8% for women in 1980. An estimated 205million men and 297million women over the age of 20 were obese a total of more than half a billion adults worldwide. Since physical activity rates over the past three decades are essentially unchanged or lower, it would seem that increased body mass has limited the weight gain due to increased energy output. As a result, obesity prevention has become an international priority. Changes in life habits and patterns, such as dietary behaviors, advancing in technology, relief, sedentary life, and decrease of lifestyle physical activities, results in an increase of obesity and weight gain among men and women. Obesity is related to increased morbidity and mortality rates due to coronary heart disease (CHD), osteoarthritis, infectious disease and cancers. Excessive body weight, in addition, increases the risk of hypertension, unhealthy lipid profile, menopauses, gallbladder disease, diabetes, some cancers, psychosocial experiences, and many other causes of chronic morbidity. Obesity, in addition, involves major expenditure and therefore represents a socioeconomic health problem of the highest magnitude. It is clear that obesity as worldwide problem results in considerable morbidities and decrease individuals abilities for keep their good health for live. In this review we try that augment this history argument, epidemically and represent the relation between physical activities and weight control among men and women. Keywords: obesity prevalence, fatness related-disease, physical fitness, weight control MOJ Women’s Health Review Article Open Access