Muscle-to-Bone Ratio in NCAA Division I Collegiate Football Players by Position.

ABSTRACT: Dengel, DR, Studee, HR, Juckett, WT, Bosch, TA, Carbuhn, AF, Stanforth, PR, and Evanoff, NG. Muscle-to-bone ratio in NCAA division I collegiate football players by position. J Strength Cond Res XX(X): 000-000, 2024-The purpose of this study was to compare the muscle-to-bone ratio (MBR) in National Collegiate Athletic Association Division I football players (collegiate football players [CFP]) to healthy, age-matched controls. In addition, we examined MBR in CFP by position. A total of 553 CFP and 261 controls had their total and regional lean mass (LM), fat mass (FM), and bone mineral content (BMC) determined by dual x-ray absorptiometry (DXA). College football players were categorized by positions defined as offensive linemen (OL), defensive linemen (DL), tight end, linebacker (LB), running back (RB), punter or kicker, quarterback (QB), defensive back (DB), and wide receiver (WR). There were significant differences between CFP and controls for total LM (80.1 ± 10.0 vs. 56.9 ± 7.8 kg), FM (22.2 ± 12.5 vs. 15.2 ± 7.1 kg), and BMC (4.3 ± 0.5 vs. 3.1 ± 0.5 kg). Although there were significant differences in body composition between CFP and controls, there was no significant differences in total MBR between CFP and controls (18.6 ± 1.4 vs. 18.8 ± 1.7). Regionally, CFP had significantly lower trunk MBR than controls (26.7 ± 2.7 vs. 28.7 ± 4.2), but no difference was seen in leg or arm MBR. Positional differences in CFP were noted as total MBR being significantly higher in DL (19.0 ± 1.4) than in DB (18.1 ± 1.3), WR (18.1 ± 1.3), and LB (18.2 ± 1.3). OL had a significantly higher total MBR (19.2 ± 1.3) than DB (18.1 ± 1.3), LB (18.2 ± 1.3), QB (18.1 ± 1.0), and WR (18.1 ± 1.3). In addition, RB had significantly higher total MBR (18.8 ± 1.3) than DB (18.1 ± 1.3) and WR (18.1 ± 1.3). This study may provide athletes and training staff with normative values when evaluating total and regional MBR with DXA.

Total and Regional Body Composition of NCAA Collegiate Female Rowing Athletes.

This study explored body composition in female NCAA Division I rowers compared to controls; and the effect of season, boat category, and oar side on body composition. This retrospective analysis of 91 rowers, and 173 age, sex, and BMI-matched controls examined total and regional fat mass (FM), lean mass (LM), bone mineral content (BMC), bone mineral density (BMD), percent body fat (%BF), and visceral adipose tissue (VAT) measured using dual X-ray absorptiometry. Two-sample t-testing was used to assess differences between rowers and controls. Repeated measures ANOVA analyzed differences across seasons. ANOVA analyzed differences between boat categories. Paired t-testing analyzed oar side versus non-oar side. Rowers had greater height (174.2; 164.1 cm), weight (75.2; 62.6 kg), LM (51.97; 41.12 kg), FM (20.74; 19.34 kg), BMC (2.82; 2.37 kg), and BMD (1.24; 1.14 g/cm2); but lower %BF (30.5%; 27.1%), and VAT (168.1; 105.0 g) than controls (p<0.05). Total, arm, and trunk muscle-to-bone ratio were greater in rowers (p<0.001). Rowers demonstrated greater arm LM (5.8 kg; 5.6 kg) and BMC (0.37 kg; 0.36 kg) in Spring compared to Fall (p<0.05). 1V8 rowers had a lower %BF than non-scoring rowers (25.7%; 29.0%; p=0.025). No differences observed between oar sides. These findings will help rowing personnel better understand body composition of female collegiate rowers.

The HERITAGE Family Study: A Review of the Effects of Exercise Training on Cardiometabolic Health, with Insights into Molecular Transducers.

The aim of the HERITAGE Family Study was to investigate individual differences in response to a standardized endurance exercise program, the role of familial aggregation, and the genetics of response levels of cardiorespiratory fitness and cardiovascular disease and diabetes risk factors. Here we summarize the findings and their potential implications for cardiometabolic health and cardiorespiratory fitness. It begins with overviews of background and planning, recruitment, testing and exercise program protocol, quality control measures, and other relevant organizational issues. A summary of findings is then provided on cardiorespiratory fitness, exercise hemodynamics, insulin and glucose metabolism, lipid and lipoprotein profiles, adiposity and abdominal visceral fat, blood levels of steroids and other hormones, markers of oxidative stress, skeletal muscle morphology and metabolic indicators, and resting metabolic rate. These summaries document the extent of the individual differences in response to a standardized and fully monitored endurance exercise program and document the importance of familial aggregation and heritability level for exercise response traits. Findings from genomic markers, muscle gene expression studies, and proteomic and metabolomics explorations are reviewed, along with lessons learned from a bioinformatics-driven analysis pipeline. The new opportunities being pursued in integrative -omics and physiology have extended considerably the expected life of HERITAGE and are being discussed in relation to the original conceptual model of the study.

The Impact of a Multimodal Sport Science-Based Prehabilitation Program on Clinical Outcomes in Abdominal Cancer Patients: A Cohort Study.

BACKGROUND: The potential for prehabilitation programs to impact clinical outcomes is uncertain in abdominal cancer patients due to the short window of time to intervene and the weakened state of the patients. To improve the effectiveness of prehabilitation intervention, a multimodal sports science approach was implemented. METHODS: Prior to cancer-related surgery, 21 patients participated in a 4-week exercise and nutrition prehabilitation program comprised of blood flow restriction exercise (BFR) and a sports nutrition supplement. Retrospective data of 71 abdominal cancer patients who underwent usual preoperative care was used as a comparator control group (CON). At 90 days post-surgery, clinical outcomes were quantified. RESULTS: Prehabilitation was associated with a shorter length of hospital stay (P = .02) with 5.5 fewer days (4.7 ± 2.1 vs 10.2 ± 1.2 days in CON) and decreased incidence of any complications (P = .03). Prehabilitation was not related to incidence of serious complications (P = .17) or readmission rate (P = .59). The prehabilitation group recorded 58% more steps on day 5 after surgery (P = .043). DISCUSSION: A 4-week home-based prehabilitation program composed of BFR training and sports nutrition supplementation was effective in reducing postoperative complications and length of hospital stay in older patients with abdominal cancer.ClinicalTrials.gov Identifier: NCT04073381.

A Mobile App With Multimodality Prehabilitation Programs for Patients Awaiting Elective Surgery: Development and Usability Study.

BACKGROUND: Complying with a prehabilitation program is difficult for patients who will undergo surgery, owing to transportation challenges and a limited intervention time window. Mobile health (mHealth) using smartphone apps has the potential to remove barriers and improve the effectiveness of prehabilitation. OBJECTIVE: This study aimed to develop a mobile app as a tool for facilitating a multidisciplinary prehabilitation protocol involving blood flow restriction training and sport nutrition supplementation. METHODS: The app was developed using "Appy Pie," a noncoding app development platform. The development process included three stages: (1) determination of principles and requirements of the app through prehabilitation research team meetings; (2) app prototype design using the Appy Pie platform; and (3) app evaluation by clinicians and exercise and fitness specialists, technical professionals from Appy Pie, and non-team-member users. RESULTS: We developed a prototype of the app with the core focus on a multidisciplinary prehabilitation program with accessory features to improve engagement and adherence to the mHealth intervention as well as research-focused features to evaluate the effects of the program on frailty status, health-related quality of life, and anxiety level among patients awaiting elective surgery. Evaluations by research members and random users (n=8) were consistently positive. CONCLUSIONS: This mobile app has great potential for improving and evaluating the effectiveness of the multidisciplinary prehabilitation intervention in the format of mHealth in future.

Prehabilitation program composed of blood flow restriction training and sports nutrition improves physical functions in abdominal cancer patients awaiting surgery.

INTRODUCTION: The impact of prehabilitation remains controversial due to a short presurgical waiting period and the diminished capacity of the patient population. A strategy to augment and optimize the effectiveness of prehabilitations for abdominal cancer patients may be found in the unlikely field of sport science. We investigated the use of blood flow restriction training and sport nutrition supplementation to augment functional capacity and increase muscle strength in twenty-four abdominal cancer patients awaiting surgery. MATERIALS AND METHODS: The sport science-based program was comprised of blood flow restriction exercise 5 to 6 times per week and a daily sports nutrition supplement containing l-citrulline, creatine monohydrate, and whey protein. RESULTS: After 4 weeks of prehabilitation, 6-min walk test, timed up and go, short physical performance battery, 5-chair stand test and physical component score of quality of life were significantly improved (all p < 0.05). Total body and appendicular lean mass as assessed by dual energy X-ray absorptiometry increased by 0.73 ± 1.04 kg (p = 0.004) and 0.42 ± 0.64 kg (p = 0.006), respectively. Total body fat mass and trunk fat mass decreased (p = 0.004 and p = 0.021). There were no significant changes in hand grip strength, fear of falling, the mental component summary of quality of life, or fasting serum concentrations of myostatin, follistatin, and growth hormone. CONCLUSION: A multimodal prehabilitation program, which encompasses blood flow restriction training and sports nutrition supplements, is both feasible and effective in improving lean mass and physical function in abdominal cancer patients prior to surgery.

Measurement of Motivation States for Physical Activity and Sedentary Behavior: Development and Validation of the CRAVE Scale.

Physical activity, and likely the motivation for it, varies throughout the day. The aim of this investigation was to create a short assessment (CRAVE: Cravings for Rest and Volitional Energy Expenditure) to measure motivation states (wants, desires, urges) for physical activity and sedentary behaviors. Five studies were conducted to develop and evaluate the construct validity and reliability of the scale, with 1,035 participants completing the scale a total of 1,697 times. In Study 1, 402 university students completed a questionnaire inquiring about the want or desire to perform behaviors "at the present moment (right now)." Items related to physical activity (e.g., "move my body") and sedentary behaviors (e.g., "do nothing active"). An exploratory structural equation model (ESEM) revealed that 10 items should be retained, loading onto two factors (5 each for Move and Rest). In Study 2, an independent sample (n = 444) confirmed these results and found that Move and Rest desires were associated with stage-of-change for exercise behavior. In Study 3, 127 community-residing participants completed the CRAVE at 6-month intervals over two years- two times each session. Across-session interclass correlations (ICC) for Move (ICC = 0.72-0.95) and Rest (ICC = 0.69-0.88) were higher than when they were measured across 24-months (Move: ICC = 0.53; Rest: ICC = 0.49), indicating wants/desires have state-like qualities. In Study 4, a maximal treadmill test was completed by 21 university students. The CRAVE was completed immediately pre and post. Move desires decreased 26% and Rest increased 74%. Changes in Move and Rest desires were moderately associated with changes in perceived physical fatigue and energy. In Study 5, 41 university students sat quietly during a 50-min lecture. They completed the CRAVE at 3 time points. Move increased 19.6% and Rest decreased 16.7%. Small correlations were detected between move and both perceived energy and tiredness, but not calmness or tension. In conclusion, the CRAVE scale has good psychometric properties. These data also support tenets of the WANT model of motivation states for movement and rest (Stults-Kolehmainen et al., 2020a). Future studies need to explore how desires to move/rest relate to dynamic changes in physical activity and sedentarism.

Bone Mineral Density Differences Across Female Olympic Lifters, Power Lifters, and Soccer Players.

ABSTRACT: Jeon, W, Harrison, JM, Stanforth, PR, and Griffin, L. Bone mineral density differences across female Olympic lifters, power lifters, and soccer players. J Strength Cond Res 35(3): 638-643, 2021-Athletic training improves bone mineral density (BMD) through repeated mechanical loading. The location, intensity, and direction of applied mechanical pressure play an important role in determining BMD, making some sports more advantageous at improving BMD at specific regions. Thirty-seven (10 power lifters [PL], 8 Olympic lifters [OL], 8 soccer players [SP], and 11 recreationally active [RA]) women participated in a cross-sectional study. We measured lumbar spine (L1-L4), femoral neck, total-body BMD, and overall body composition (total fat mass, lean mass, percent body fat) with dual-energy x-ray absorptiometry. All athletic groups had greater total BMD than RA (p = 0.01 [PL]; p < 0.001 [OL]; p = 0.01 [SP]). Olympic lifters had the highest total BMD than all other athletic groups. Olympic lifters had the significantly greater total BMD than PL (p = 0.018), but there was no difference in total BMD between PL and SP. As compared with RA, OL showed greater BMD at both the total lumbar spine (p = 0.002) and the femoral neck (p = 0.007), whereas PL showed greater BMD only for the total lumbar spine (p = 0.019) and SP showed greater BMD only for the femoral neck (p = 0.002). Olympic-style lifting includes both high-impact and odd-impact loading modalities that are associated with the highest BMD at both the lumbar spine and femoral neck.

Positional Body Composition of Female Division I Collegiate Volleyball Players.

Bisch, KL, Bosch, TA, Carbuhn, A, Stanforth, PR, Oliver, JM, Bach, CW, and Dengel, DR. Positional body composition of female division I collegiate volleyball players. J Strength Cond Res 34(11): 3055-3061, 2020-The primary study objective was to measure positional differences in total and regional body composition among female NCAA Division I collegiate volleyball players using dual X-ray absorptiometry (DXA). The secondary objective was to examine normative age curves for fat and lean mass (LM) variables. Ninety female volleyball players from 5 universities received a DXA scan. Athletes were categorized by position: middle blocker (MB = 31), outside hitter (OH = 32), setter (ST = 9), and Libero (LB = 18). Height, body mass, total and regional fat mass (FM), LM, bone mineral density (BMD), and abdominal visceral adipose tissue were measured by DXA. Body mass distribution ratios were calculated. The secondary age analysis included a subset of 153 DXA scans (n = 83, ages 18-21 years). Front row players (i.e., MB and OH) had significantly greater total and regional LM and BMD measures (p < 0.05, all), compared with non-front row players (i.e., LB and ST). Differences in total LM (p < 0.001) were significantly influenced by height. Front row players had consistently lower mass distribution ratios compared with non-front row players (p < 0.05, all). Lean mass index (LMI, p = 0.752) and FM index (FMI, p = 0.392) were not significantly different across ages. Back row players have greater relative upper body mass, whereas mass in front row players is more evenly distributed between the upper and lower body. Bone mineral density differences may be influenced by repeated impact of jumping during the attacking and blocking actions of front row players. Minimal changes in LMI and fluctuations in FMI can be expected across an athlete's career.

Body Composition of National Collegiate Athletic Association (NCAA) Division I Female Soccer Athletes through Competitive Seasons.

The purpose of this study was to examine body composition of National Collegiate Athletic Association Division I female soccer players by position and season. One hundred seventy-five female athletes were categorized by positions of forward (n=47), midfielder (n=51), defender (n=57), and goalkeeper (n=20). A dual X-ray absorptiometry scan assessed percent body fat, total lean mass, total fat mass, arm and leg lean mass and fat mass, and visceral adipose tissue. Goalkeepers had significantly higher total, arm, and leg lean mass and fat mass compared to all other positions (p<0.05). For seasonal changes, body fat percentage was significantly higher in winter off-season (26.7%) compared to summer off-season (25.7%) and pre-season (25.8%; p<0.01) for all positions. Total and leg lean mass was significantly lower in winter off-season compared to all other seasons, and total lean mass was significantly higher in summer off-season than pre-season (p<0.01). Overall, goalkeepers were significantly different than all other positions. Body fat percentage increased and lean mass decreased in winter off-season indicating potential undesired changes in training and/or nutrition over the break whereas lean mass was the highest in summer off-season potentially reflecting the emphasis on resistance training and increased volume of training.

Total and Regional Body Composition of NCAA Division I Collegiate Basketball Athletes.

This study aimed to examine body composition using dual X-ray absorptiometry (DXA) in male and female NCAA Division I collegiate basketball athletes. Two-hundred ten (male [M]/female [F]=88/122) basketball athletes' total and regional fat mass, lean mass, bone mineral density, and visceral adipose tissue were measured. Athletes were classified as: point guards (M/F=27/34), shooting guards (M/F=18/27), small forwards (M/F=13/18), power forwards (M/F=21/27), and centers (M/F=9/16). ANOVA and Tukey's HSD assessed positional differences by sex. In males, centers and power forwards had greater total fat mass (p<0.025), lean mass (p≤0.001), and visceral adipose tissue (p<0.001) than other positions. Male centers had greater arm and leg fat mass and lean mass than point guards, shooting guards, and small forwards (p≤0.049), and greater arm bone mineral density than point guards (p=0.015). In females, centers had greater total fat mass (p<0.001) vs. other positions and greater total lean mass, arm fat and lean masses, arm and leg bone mineral density, and visceral adipose tissue vs. point guards and shooting guards (p≤0.005). Female point guards had lower total bone mineral density than power forwards (p=0.008). In conclusion, these sex- and position-specific total and regional body composition measurements in collegiate basketball players provide population-specific normative data.

Body Composition and Bone Mineral Density of Division 1 Collegiate Track and Field Athletes, a Consortium of College Athlete Research (C-CAR) Study.

The purpose of the present study was to generate normative values for total and regional body composition in male and female Division 1 collegiate track and field athletes using dual X-ray absorptiometry. We also sought to examine body composition by event and sex. Data were used from the Consortium of College Athlete Research group. A total of 590 (male [M]/female [F] = 274/316) athletes had their height, weight, total and regional fat mass (FM), lean mass, and bone mineral density (BMD) measured. Athletes were classified into 1 of 7 categories: Jumps (M/F = 28/30); Long Distance (M/F = 104/110), Middle Distance (M/F = 27/24), Multievent (M/F = 11/9), Pole Vault (M/F = 21/27), Sprints (M/F = 54/96), and Throws (M/F = 29/20). Total and regional differences between events and sex were assessed by analysis of variance. Except for male and female throwers, all other track and field athletes' mean percent body fat (M: 10.3%-12.6%, F: 17.5%-21.6%) and visceral FM (<500 g) was low, but in a healthy range. As expected, throwers had significantly (p < 0.05) higher total and regional FM and lean mass than other events. In addition, male (1.55 ± 0.11 g/cm2) and female (1.40 ± 0.12 g/cm2) throwers had significantly greater BMD than all other events while male (1.25 ± 0.10 g/cm2) and female (1.16 ± 0.09 g/cm2) distance runners had significantly lower BMD than all other events. In conclusion, track athletes' body composition differed across events for both males and females. These measurements provide normative data on NCAA Division 1 male and female track and field athletes.

Total and Regional Body Composition of NCAA Division I Collegiate Female Softball Athletes.

The purpose of this study was to evaluate total, regional, and throwing versus non-throwing arm body composition measures across the 4 major positions of NCAA Division I female softball players using dual X-ray absorptiometry (DXA) (n=128). Total and regional total mass (TM), fat mass (FM), lean mass (LM), bone mineral density (BMD), bone mineral content (BMC), and visceral adipose tissue were measured. Athletes were separated into: pitchers (n=32), catchers (n=13), outfielders (n=39), and infielders (n=44). ANOVA and Tukey's HSD assessed total and regional differences between positions. Although no significant total or regional LM differences were observed across positions, outfielders had significantly (p=0.006-0.047) lower total-body, arm, and trunk TM and FM, leg FM, and leg BMC in comparison to pitchers. The throwing arm had significantly (p<0.0001-0.018) greater LM, BMD, and BMC than the non-throwing arm for all positions. Notably, there were minimal body composition differences among softball positions, with the primary differences being that pitchers had larger total and regional fat values than outfielders. The throwing arm of all positions had greater LM, BMD, and BMC than the non-throwing arm. These values can be used by coaches and trainers as descriptive DXA data for collegiate softball players.

Total and Regional Body Composition of NCAA Division I Collegiate Baseball Athletes.

This study's purpose was to evaluate total, regional, and throwing versus non-throwing arm body composition measurements between various positions of NCAA Division I male baseball players using dual X-ray absorptiometry (DXA). Two hundred and one collegiate baseball athletes were measured using DXA. Visceral adipose tissue (VAT), total and regional fat mass (FM), lean mass (LM), and bone mineral density (BMD) were measured. Athletes were separated into: pitchers (n=92), catchers (n=25), outfielders (n=43), and infielders (n=41). ANOVA and Tukey's honest significant difference assessed total and regional differences between positions. Infielders had significantly (p<0.05) lower total LM than pitchers and outfielders. Additionally, outfielders had significantly lower total FM compared to pitchers and catchers. No significant differences between positions were observed for total BMD and VAT. Pitchers' and infielders' throwing arm demonstrated significantly greater total mass, FM, LM, and BMD compared to the non-throwing arm. Further, outfielders' throwing arm total mass, LM, and BMD were significantly higher vs. the non-throwing arm. Significant differences were observed in total and regional body composition measurements across position, in addition to differences in throwing arm vs. non-throwing arm composition. These measurement values are important to coaches and trainers as normative positional DXA data for collegiate baseball players.

Body Composition and Bone Mineral Density of Division 1 Collegiate Football Players: A Consortium of College Athlete Research Study.

Bosch, TA, Carbuhn, AF, Stanforth, PR, Oliver, JM, Keller, KA, and Dengel, DR. Body composition and bone mineral density of Division 1 collegiate football players: a consortium of college athlete research study. J Strength Cond Res 33(5): 1339-1346, 2019-The purpose of this study was to generate normative data for total and regional body composition in Division 1 collegiate football players using dual-energy x-ray absorptiometry (DXA) and examine positional differences in total and regional measurements. Data were used from the Consortium of College Athlete Research (C-CAR) group. Four hundred sixty-seven players were included in this study. Height, body mass, total and regional fat mass, lean mass, and bone mineral density were measured in each athlete in the preseason (June-August). Players were categorized by their offensive or defensive position for comparisons. Linemen tended to have the higher fat and lean mass measures (p ≤ 0.05 for all) compared with other positions. Positions that mirror each other (e.g. linemen) had similar body composition and body ratios. All positions were classified as overweight or obese based on body mass index (BMI) (>25 kg·m), yet other than offensive and defensive linemen, all positions had healthy percent body fat (13-20%) and low visceral fat mass (<500 g). The data presented here provide normative positional data for total and regional fat mass, lean mass, and bone density in Division 1 collegiate football players. Player position had a significant effect on body composition measures and is likely associated with on-field positional requirements. From a player's health perspective, although all positions had relatively high BMI values, most positions had relatively low body fat and visceral fat, which is important for the health of players during and after their playing career. The increased accuracy and reliability of DXA provides greater information, regarding positional differences in college football players compared with other methods.

Bone Mineral Content and Density Among Female NCAA Division I Athletes Across the Competitive Season and Over a Multi-Year Time Frame.

Stanforth, D, Lu, T, Stults-Kolehmainen, MA, Crim, BN, and Stanforth, PR. Bone mineral content and density among female NCAA Division I athletes across the competitive season and over a multi-year time frame. J Strength Cond Res 30(10): 2828-2838, 2016-Longitudinal and cross-sectional bone mineral content (BMC) and bone mineral density (BMD) comparisons were made among impact and nonimpact sports. Female collegiate athletes, 18-23 years of age, from basketball (BB; n = 38), soccer (SOC; n = 47), swimming (SW; n = 52), track sprinters and jumpers (TR; n = 49), and volleyball (VB; n = 26) had BMC/BMD measures preseason and postseason over 3 years. Control groups of 85 college females, 18-24 years of age, who completed 2 tests 1-3 years apart and of 170 college females, 18-20 years of age, were used for the longitudinal and cross-sectional analyses, respectively. A restricted maximum likelihood linear mixed model regression analysis with a compound symmetric heterogeneous variance-covariance matrix structure was used for all analyses (p ≤ 0.05). Increases from year-1 preseason to year-3 postseason included the following: total BMC (3.3%), total BMD (1.4%), and spine BMD (4.5%) for BB; total BMC (1.5%) and leg BMD (1.2%) for SOC; arm (1.8%), leg (1.9%), and total BMD (5.7%) for SW; total BMC (2.0%), arm (1.7%), leg (2.3%), pelvis (3.4%), spine (6.0%), and total BMD (2.3%) for TR; and arm (4.1%), leg (2.0%), pelvis (2.0%), spine (2.0%), and total BMD (2.7%) for VB. Comparisons among sports determined that BB had higher BMC and BMD values than all other sports for all variables except spine and total BMD; BB, SOC, TR, and VB had higher total BMC (11-29%), leg BMD (13-20%), and total BMD (9-15%) than SW and CON, and there were few differences among SOC, TR, and VB. In conclusion, small, significant increases in many BMC and BMD measures occur during female athlete's collegiate careers. The BMC and BMD differences between impact and nonimpact sports are large compared with smaller differences within impact sports.

Prediction of Android and Gynoid Body Adiposity via a Three-dimensional Stereovision Body Imaging System and Dual-Energy X-ray Absorptiometry.

OBJECTIVE: Current methods for measuring regional body fat are expensive and inconvenient compared to the relative cost-effectiveness and ease of use of a stereovision body imaging (SBI) system. The primary goal of this research is to develop prediction models for android and gynoid fat by body measurements assessed via SBI and dual-energy x-ray absorptiometry (DXA). Subsequently, mathematical equations for prediction of total and regional (trunk, leg) body adiposity were established via parameters measured by SBI and DXA. METHODS: A total of 121 participants were randomly assigned into primary and cross-validation groups. Body measurements were obtained via traditional anthropometrics, SBI, and DXA. Multiple regression analysis was conducted to develop mathematical equations by demographics and SBI assessed body measurements as independent variables and body adiposity (fat mass and percentage fat) as dependent variables. The validity of the prediction models was evaluated by a split sample method and Bland-Altman analysis. RESULTS: The R(2) of the prediction equations for fat mass and percentage body fat were 93.2% and 76.4% for android and 91.4% and 66.5% for gynoid, respectively. The limits of agreement for the fat mass and percentage fat were -0.06 ± 0.87 kg and -0.11% ± 1.97% for android and -0.04 ± 1.58 kg and -0.19% ± 4.27% for gynoid. Prediction values for fat mass and percentage fat were 94.6% and 88.9% for total body, 93.9% and 71.0% for trunk, and 92.4% and 64.1% for leg, respectively. CONCLUSIONS: The three-dimensional (3D) SBI produces reliable parameters that can predict android and gynoid as well as total and regional (trunk, leg) fat mass.

Body composition changes among female NCAA division 1 athletes across the competitive season and over a multiyear time frame.

Body composition can affect athletic performance. Numerous studies have documented changes in body composition in female collegiate athletes from pre- to postseason; however, longitudinal studies examining changes across years are scarce. Therefore, the primary purpose of this study was to assess longitudinal body composition changes among female collegiate athletes across 3 years. Two hundred twelve female athletes from basketball (BB; n = 38), soccer (SOC; n = 47), swimming (SW; n = 52), track (sprinters and jumpers; TR; n = 49), and volleyball (VB; n = 26) with an initial mean age of 19.2 ± 1.2 years, height of 172.4 ± 8.9 cm, and total mass of 66.9 ± 9.0 kg had body composition assessments using dual-energy x-ray absorptiometry pre- and postseason over 3 years. A restricted maximum-likelihood linear mixed model regression analysis examined body composition differences by sport and year. Changes (p < 0.05) over 3 years included the following: Lean mass increased in VB from year 1 to 2 (0.7 kg), year 2 to 3 (1.1 kg), and year 1 to 3 (1.8 kg) and in SW from year 1 to 3 (0.6 kg); and percent body fat (%BF) increased in BB from year 1 to 3 (1.7%). There were no changes in SOC or TR. These results indicate that during their college careers, female collegiate athletes can be expected to maintain their %BF and athletes in sports like SW and VB can anticipate an increase in lean mass, but the increases may be less than many athletes, coaches, and trainers envision.

Fat in android, trunk, and peripheral regions varies by ethnicity and race in college aged women.

The aim of this study was to determine whether quantity of fat is different across the central (i.e., android, trunk) and peripheral (i.e., arm, leg, and gynoid) regions among young African-American (AA), Asian (AS), Hispanic (HI), and non-Hispanic white (NHW) women. A cohort of 1,161 women (18-30 years) from university physical activity classes were assessed for body composition via dual-emission X-ray absorptiometry (DXA). The mean total body fat percent (TBF%, x = 31.0 ± 7.36%, range = 11.4-54.4%) indicates sufficient variability for the aims. A linear mixed model (LMM) revealed an ethnicity by region fat% interaction (P < 0.0001). Differences existed between ethnicities for each region fat% (all P's < 0.0001) except between HI and AA for the arm region (P = 0.0086) and between AS and NHW for all peripheral regions (P > 0.05). AAs had the highest fat% and HI had the second highest fat% for each region. AS had the third highest fat% for the trunk and android regions. For each ethnicity, the gynoid region had the greatest fat%, followed by the android region, whereas the arm region had the lowest fat%. Future research needs to determine if ethnic differences in central body fat in young women are associated with health outcomes such as cardiovascular disease and insulin resistance.