This investigation examined the impact of a cycle ergometry exercise test (CET) on body composition determined using leg-to-leg bioelectrical impedance analysis (BIA; Tanita Model TPF-305). Fifty three children (25 males, 28 females) aged 10-12 yr participated. BIA measures of body fat (BF) were obtained immediately before and within five min of a multistage CET administered to assess peak oxygen consumption. Correlations (P = 0.01) of 0.99 were noted between the pre and post CET measures of BF. A systematic difference was not found in BIA measures obtained before and after CET. BF decreased by 0.4 and 1.2% following CET in the male and female subjects, respectively.
Fredric L. Goss, Robert J. Robertson, John Dube, Jason Rutkowski, Joseph Andreacci, Brooke Lenz, Julie Ranalli and Krisi Frazee
Francis X. Short and Joseph P. Winnick
This manuscript examines the validity and reliability of the tests used to measure body composition in the Brockport Physical Fitness Test. More specifically, information is provided on skinfold measures and body mass index and their applicability to youngsters with mental retardation and mild limitations in fitness, visual impairment (blindness), cerebral palsy, spinal cord injury, or congenital anomalies or amputations. The rationale for criterion-referenced standards for these test items for youngsters with these disabilities is provided along with some data on attainability of those standards. Possible ideas for future research are recommended.
Joan M. Eckerson, Dona J. Housh, Terry J. Housh and Glen O. Johnson
The purpose of this investigation was to determine the changes in body composition, isokinetic strength, and muscular power in high school wrestlers across a season of competition. Wrestlers were measured (preseason and postseason) for body composition and isokinetic peak torque for flexion and extension of the dominant forearm and leg. Each subject also completed Wingate anaerobic tests to determine changes in mean power and peak power (PP) of the legs. The results indicated that body weight (BW), fat weight, and percent fat decreased (p < .002) across the wrestling season. PP and absolute peak torque for forearm and leg extension (LE) at 30°·s−1; forearm flexion (FF) at 30, 180, and 300°·s−1; and leg flexion (LF) at 180 and 300°·s−1 were significantly (p < .05) lower postseason. Relative peak torque (adjusted for BW) decreased (p < .05) across the season for LE at 30°·s−1 as well as FF and LF at 180°·s−1. Therefore, changes in BW were not associated with functional advantages in terms of strength or muscular power.
Mary A. Steinhardt and Debra J. Macklem
The use of skinfold measurements is a popular method to determine percentage of body fat because of its relative simplicity. Although attention has been paid to its technical accuracy and validity, less consideration has been given to the psychological impact on participants. The purpose of this study was to determine students’ (N = 128) reactions to having skinfold measurements taken in university physical education classes. Skinfold measurements were taken, and a questionnaire administered during the 2nd and 13th weeks of the semester. The questionnaire was used to assess (a) if students were self-conscious or uncomfortable during the measurements, (b) if knowing percent body fat motivated students to exercise, and (c) if the procedure should remain a standard part of class. Descriptive results indicated most students agreed that percent fat measurement was a valuable part of the class. On the pretest, after controlling for sex, regression analysis revealed that percent fat significantly predicted feelings of self-consciousness (R 2 =.08; β = .36) and motivation to exercise (R 2 = .07; β.24). On the posttest, percent fat again predicted feelings of self-consciousness (R 2 = .21; β = .58) but did not predict motivation to exercise. Also, students with greater percent fat felt the body composition assessment should be optional (R 2 = .08; β = −.36). Although results of this study support body composition assessment in university health-related activity classes, the need for sensitivity to the emotional needs and privacy of individuals is recommended.
Maija Hassinen, Pirjo Komulainen, Timo A. Lakka, Sari B. Väisänen and Rainer Rauramaa
The epidemic of sedentary lifestyle and obesity increases the risk of disability with aging. We studied the relationships of body composition, physical activity, and muscular fitness with balance and walking ability.
Men and women, age 70 to 74 y (n = 146), were randomly selected from the Finnish population register. Body composition [body weight, body-mass index (BMI), waist circumference], physical activity (questionnaire), muscular fitness (hand-grip strength), balance (commonly used field tests), and walking ability (20 m walking test) were assessed.
BMI (r = –0.287, P < 0.001), waist circumference (r = –0.260, P = 0.002), physical activity (r = 0.206, P = 0.013), and hand-grip strength (r = 0.244, P = 0.003) correlated with balance. BMI (r = 0.330, P < 0.001), waist circumference (r = 0.237, P = 0.004), physical activity (r = –0.252, P = 0.002), and hand-grip strength (r = –0.307, P < 0.001) also correlated with walking time.
Overweight and central obesity as well as low muscular fitness associate with impaired balance and walking ability in the elderly.
Tibor Hortobágyi, Richard G. Israel, Joseph A. Houmard, Kevin F. O'Brien, Robert A. Johns and Jennifer M. Wells
Four methods of assessing body composition were compared in 55 black and 35 white, Division 1, American football players. Percent body fat (%BF) was estimated with hydrostatic weighing at residual volume, corrected for race; seven-site skinfolds (7 SF), corrected for race; bioelectrical impedance analysis (BIA); and near-infrared spectrophotometry (NIR). Percent body fat with HW in blacks (mean = 14.7%) and whites (19.7%) did not differ (P > .05) from %>BF with 7 SF (blacks, 14.7%; whites, 19.0%). In relation to HW, BIA significantly (P < .05) overpredicted (blacks: 20.1%, SEE = 3.2%; whites; 22.3%, SEE = 4.3%) and NiR underpredicted %BF (blacks; 12.6%, SEE = 3.9%; whites; 17.7%, SEE = 3.6%). The contribution of BIA variables (resistance, phase angle, conductance) and NIR optical density to predict %BF was trivial compared to body mass index. It appears that race may not substantially influence %BF prediction by NIR and BIA. It was concluded that when considering the cost and expertise required with NIR and BIA, SF measurements appear to be a superior alternative for rapid and accurate body composition assessment of athletes, independent of race.
Marc Bonis, Mark Loftin, Richard Speaker and Anthony Kontos
The purpose of the study was to investigate the seasonal relationship of athletic amenorrhea and body composition in elite, adolescent, cross-country runners. The participants consisted of 28 female adolescent cross-country runners (mean age ± SD = 15.4 ± 1.5 years); 17 eumenorrheics and 11 amenorrheics. The participants’ body composition was measured pre- and postseason using dual-energy X-ray Absorptiometer (DXA). The eumenorrheics’ postseason BMD was significantly greater than the amenorrheics’ postseason BMD (F(1,54) = 16.22, p < .05, partial η 2 = .231). The eumenorrheics’ postseason bodyweight (F(1,54) = 7.65, p < .05, partial η 2 = .124), BF (F(1,54) = 8.56, p < .05, partial η 2 = .137), and BMC (F(1,54) = 8.52, p < .05, partial η 2 = .136) were significantly greater than the amenorrheic subgroup. There was also a significant seasonal increase in BMD (t(27) = –4.01, p < .05) for the overall group and the eumenorrheic subgroup (t(16) = –3.90, p < .05). Bodyweight best predicted BMD (F(1,26) = 46.434, p < .05, R2 = .641). In the study, athletic amenorrhea was highly associated with lower levels of BMD in the participants, and crosscountry running was highly associated with increased BMD.
Johann C. Bilsborough, Thomas Kempton, Kate Greenway, Justin Cordy and Aaron J. Coutts
To compare development and variations in body composition of early-, mid-, and late-career professional Australian Football (AF) players over 3 successive seasons.
Regional and total-body composition (body mass [BM], fat mass [FM], fat-free soft-tissue mass [FFSTM], and bone mineral content [BMC]) were assessed 4 times, at the same time of each season—start preseason (SP), end preseason (EP), midseason (MS), and end season (ES)—from 22 professional AF players using pencil-beam dual-energy X-ray absorptiometry. Nutritional intake for each player was evaluated concomitantly using 3-d food diaries. Players were classified according to their age at the beginning of the observational period as either early- (<21 y, n = 8), mid- (21 to 25 y, n = 9), or late- (>25 y, n = 5) career athletes.
Early-career players had lower FFSTM, BMC, and BM than mid- and late-career throughout. FM and %FM had greatest variability, particularly in the early-career players. FM reduced and FFSTM increased from SP to EP, while FM and FFSTM decreased from EP to MS. FM increased and FFSTM decreased from MS to ES, while FM and FFSTM increased during the off-season.
Early-career players may benefit from greater emphasis on specific nutrition and resistance-training strategies aimed at increasing FFSTM, while all players should balance training and diet toward the end of season to minimize increases in FM.
Jace A. Delaney, Heidi R. Thornton, Tannath J. Scott, David A. Ballard, Grant M. Duthie, Lisa G. Wood and Ben J. Dascombe
High levels of lean mass are important in collision-based sports for the development of strength and power, which may also assist during contact situations. While skinfold-based measures have been shown to be appropriate for cross-sectional assessments of body composition, their utility in tracking changes in lean mass is less clear.
To determine the most effective method of quantifying changes in lean mass in rugby league athletes.
Body composition of 21 professional rugby league players was assessed on 2 or 3 occasions separated by ≥6 wk, including bioelectrical impedance analysis (BIA), leanmass index (LMI), and a skinfold-based prediction equation (SkF). Dual-X-ray absorptiometry provided a criterion measure of fat-free mass (FFM). Correlation coefficients (r) and standard errors of the estimate (SEE) were used as measures of validity for the estimates.
All 3 practical estimates exhibited strong validity for cross-sectional assessments of FFM (r > .9, P < .001). The correlation between change scores was stronger for the LMI (r = .69, SEE 1.3 kg) and the SkF method (r = .66, SEE = 1.4 kg) than for BIA (r = .50, SEE = 1.6 kg).
The LMI is probably as accurate in predicting changes in FFM as SkF and very likely to be more appropriate than BIA. The LMI offers an adequate, practical alternative for assessing in FFM among rugby league athletes.
Heidi L. Petersen, C. Ted Peterson, Manju B. Reddy, Kathy B. Hanson, James H. Swain, Rick L. Sharp and D. Lee Alekel
This study determined the effect of training on body composition, dietary intake, and iron status of eumenorrheic female collegiate swimmers (n = 18) and divers (n = 6) preseason and after 16 wk of training. Athletes trained on dryland (resistance, strength, fexibility) 3 d/wk, 1.5 h/d and in-water 6 d/wk, nine, 2-h sessions per week (6400 to 10,000 kJ/d). Body-mass index (kg/m2; P = 0.05), waist and hip circumferences (P ≤ 0.0001), whole body fat mass (P = 0.0002), and percentage body fat (P ≤ 0.0001) decreased, whereas lean mass increased (P = 0.028). Using dual-energy X-ray absorptiometry, we found no change in regional lean mass, but fat decreased at the waist (P = 0.0002), hip (P = 0.0002), and thigh (P = 0.002). Energy intake (10,061 ± 3617 kJ/d) did not change, but dietary quality improved with training, as refected by increased intakes of fber (P = 0.036), iron (P = 0.015), vitamin C (P = 0.029), vitamin B-6 (P = 0.032), and fruit (P = 0.003). Iron status improved as refected by slight increases in hemoglobin (P = 0.046) and hematocrit (P = 0.014) and decreases in serum transferrin receptor (P ≤ 0.0001). Studies are needed to further evaluate body composition and iron status in relation to dietary intake in female swimmers.