The study was designed to determine how body fat percentage (BF%), body fat distribution (BFD), and abdominal muscular endurance (AME) relate to pulmonary function (PF) as measured by the forced vital capacity (FVC), the forced expiratory volume in 1 s (FEV 1 ), the FEV 1 /FVC ratio, and the maximal inspiratory pressure (MIP) among college (M = 22.82, SD = 2.45 yr) males (N = 60). Multiple regression analyses were calculated. A ceiling effect for AME was found; hence, AME was not used as a

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... ctor variable in the multiple regression analyses. The distribution of MIP values was leptokurtic; therefore, MIP was excluded from the analysis. Body weight (p = .00) and body height (p = .03) were positively related to FVC. BF% was inversely (p = .05) related to FVC but was unrelated to FEV 1 or FEV 1 /FVC. The predictor variable BFD was unrelated to FVC, FEV 1 , or FEV 1 /FVC. In conclusion, increased proportions of fat were inversely related to FVC in college males. Key Points: • Body fat percentage is inversely related to forced vital capacity in college males. • Increased body fat proportions may decrease intra-thoracic size and consequently pulmonary function. • Increased body fat proportions may diminish dynamic compliance of the lungs thereby affecting pulmonary function. • College-age males need to be aware that an increase in body fat percentage is potentially related to impaired pulmonary function. race, inherited or environmentally induced birth-defects, genetic predisposition, and accidents (1, 13). Modifiable factors include environment, body weight, body composition, posture, and specific diseases (18) . Body composition has been closely related to health factors. Not only the amount of fat in the body (i.e., increased body fat percentage) has been related to diseases, but also the patterns of fat deposition in the body. Android (deposition of fat in the trunk area) and gynoid (fat deposition in the hip and thigh areas) are the two main patterns of fat deposition, with the android pattern related to greater health risk than the gynoid pattern (15). These patterns of body fat distribution have been associated with the development of diseases such as obesity, hypertension, diabetes, glucose intolerance, blood lipid disorders, hyperinsulinaemia, impaired lung function, coronary artery disease, and premature death (9, 10, 12, 14). Overweight and increased body fat percentage (BF%) have been related to a general decline in lung function by diminishing pulmonary dynamic compliance and decreasing the mechanical efficiency of ventilatory muscles, chest wall compliance, lung vital capacity, and expiratory reserve volume (ERV; 5, 7, 8) . Even though an increased BF% was positively related to pulmonary function (i.e., ERV) in prepubertal girls (6) , the opposite has been commonly found in the research literature (5, 7, 8, 28) . Increased mass in the trunk has been hypothesized to impair pulmonary mechanic function (7) . Although researchers (12) have reported that increased muscularity may improve lung function in humans, others (7) have previously concluded that upper body muscle development (e.g., among gymnasts) was associated with impaired lung function explained probably by a reduction of the end-expiratory size of the thorax due to the increased muscle tissue mass. As scientific evidence relates body composition with a possible deleterious effect on pulmonary function, it seems also reasonable and logical to study how physical variables relate to pulmonary functions in humans. Although the relationship between pulmonary and anthropometric variables has been studied separately, the relationship among abdominal muscular endurance, body composition, and pulmonary function apparently has never been reported. This study was designed to determine how body fat percentage, body fat distribution, and abdominal muscular endurance relate to pulmonary function, specifically to FVC (Model 1), FEV 1 (Model 2), the FEV 1 /FVC ratio (Model 3), and maximal inspiratory pressure (MIP; Model 4) for 20-to 29-year-old males. High pulmonary function values as measured by the FVC, FEV 1 , FEV 1 /FVC, and MIP were hypothesized to correlate with abdominal muscular endurance, yet increased body fat percentages and android patterns of body fat distribution were expected to negatively correlate with FVC, FEV 1 , FEV 1 /FVC, and MIP.