Estimation of Body Composition in Competitive Swimmers by Means of Three Different Techniques

Abstract

Up to now controversial reports have been published in regard to the beneficial effects of swimming, a non-weight-bearing activity, on bone mass (BM). Therefore, the aim of this study was to investigate the effects of competitive swimming practice on the bone mineral density (BMD) and bone mineral content (BMC) as well as on the different factors of body composition. For this purpose, competitive swimmers (16 males and 16 females) were selected as subjects in order to investigate the influence of swimming on the three main factors of body composition (BMC, lean body mass [LBM] and body fat [BF]) of the human body. The latter were estimated using three different approaches: the skinfold, the dual energy x-ray absorptiometry (DEXA) and the whole body potassium (K-40) methods. Since BM and LBM are also related, the possible correlations between shoulder strength (extensions and flexion movements) and performance with BMD, BMC, LBM and BF were also investigated. Our results showed that BMD was not affected by swimming exercise since z (%) values were similar between swimmers and their respective age-matched controls. Swimmers also showed lower BF and increased LBM in the region of upper extremities (arms and trunk) as compared to their lower extremities (legs), a finding which is typical for the sport they are trained for. Also, comparison between sexes showed that males had a more central distribution of fat when compared to females, in which BF was built up in the region of legs. Furthermore, shoulder strength and performance were significantly related (p < 0.05) to age, BMC, and LBM while performance was also significantly related (p < 0.05) to all the other BM indices. So, mineralization of the bone is important for shoulder muscular strength which is subsequently related to performance. We used the DEXA because it enabled the direct estimation of the three factors of body composition (BM, BF and LBM).

Seasonal Effects on Body Composition, Muscle Characteristics, and Performance of Collegiate Swimmers and Divers

“…Although the findings were not significant in the current study, males increased in body mass (D ¼ 0.9 kg, P ¼ .15), which appeared to be largely attributable to an increase in LM (D ¼ 0.8 kg, P ¼ .23). Previous investigators 12,15 reported that 13 However, Avlonitou et al 16 reported BMD values (as measured by DEXA) of female and male competitive swimmers that were similar to those of age-matched controls. Our DEXA measures of BMD also indicated that both male and female swimmers were in the healthy range for total body BMD Z scores compared with age-matched controls (females ¼ À0.12 6 0.8, males ¼À0.26 6 1.3).…”

Bone Mineral Density of 704 Amateur Sportsmen Involved in Different Physical Activities

“…Our results are in agreement with results of previous studies. Soccer [4], basketball [5,6], volleyball [5][6][7], gymnastics [4,6], weightlifting [8] and ice hockey [9] are associated with a high TB BMD, whereas cyclists [10], horse riders [11] and especially swimmers [5,9,10,[12][13][14][15] have a TB BMD similar to that of a sedentary group. These results emphasize the effect of gravity on bone mass.…”

Aquatic Therapy: Scientific Foundations and Clinical Rehabilitation Applications

“…The effect of exercise, both impact loading such as running and of nonimpact exercise such as cycling and swimming appears to clearly favor impact‐loading exercise in both young men and women. This advantage appears to hold through early adulthood as measured in elite competitive athletes [151,159‐165]. There does seem to be a slight difference between men and women during these later competitive years, with men building slightly more bone than women [150,151,159,165,166].…”

“…This advantage appears to hold through early adulthood as measured in elite competitive athletes [151,159‐165]. There does seem to be a slight difference between men and women during these later competitive years, with men building slightly more bone than women [150,151,159,165,166]. Even in later years, the athletes have greater bone mineral content than nonathletic controls, which demonstrates the value of early‐life athletic activity, especially for women who are at greater risk for osteoporosis.…”