Browsing by Author "Fedewa, Michael, V"
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Item Agreement Between A 2-Dimensional Digital Image-Based 3-Compartment Body Composition Model and Dual Energy X-Ray Absorptiometry for The Estimation of Relative Adiposity(Elsevier, 2022) Sullivan, Katherine; Metoyer, Casey J.; Hornikel, Bjoern; Holmes, Clifton J.; Nickerson, Brett S.; Esco, Michael R.; Fedewa, Michael, V; University of Alabama Tuscaloosa; Washington University (WUSTL); Texas A&M International UniversityThe purpose of this study was to compare relative adiposity (%Fat) derived from a 2-dimensional image-based 3-component (3C) model (%Fat(3C-IMAGE)) and dual-energy X-ray absorptiometry (DXA) (%Fat(DXA)) against a 5-component (5C) laboratory criterion (%Fat(5C)). 57 participants were included (63.2% male, 84.2% White/Caucasian, 22.5 +/- 4.7 yrs., 23.9 +/- 2.8 kg/m(2)). For each participant, body mass and standing height were measured to the nearest 0.1 kg and 0.1 cm, respectively. A digital image of each participant was taken using a 9.7 inch, 16g iPad Air 2 and analyzed using a commercially available application (version 1.1.2, made Health and Fitness, USA) for the estimation of body volume (BV) and inclusion in %Fat(3C-IMAGE). %Fat(3C-IMAGE) and %Fat(5C) included measures of total body water derived from bioimpedance spectroscopy. The criterion %Fat(5C) included BV estimates derived from underwater weighing and bone mineral content measures via DXA. %Fat(DXA) estimates were calculated from a whole-body DXA scan. A standardized mean effect size (ES) assessed the magnitude of differences between models with values of 0.2, 0.5, and 0.8 for small, moderate, and large differences, respectively. Data are presented as mean +/- standard deviation. A strong correlation (r = 0.94, p <.001) and small mean difference (ES = 0.24, p <.001) was observed between %Fat(3C-IMAGE) (19.20 +/- 5.80) and %Fat(5C) (17.69 +/- 6.20) whereas a strong correlation (r = 0.87, p <.001) and moderate-large mean difference (ES = 0.70, p <.001) was observed between %Fat DXA (22.01 +/- 6.81) and %Fat(5C). Furthermore, %Fat(3C-IMAGE )(SEE = 2.20 %Fat, TE= 2.6) exhibited smaller SEE and TE than %Fat(DXA) (SEE = 3.14 %Fat, TE = 5.5). The 3C image-based model performed slightly better in our sample of young adults than the DXA 3C model. Thus, the 2D image analysis program provides an accurate and non-invasive estimate of %Fat within a 3C model in young adults. Compared to DXA, the 3C image-based model allows for a more cost-effective and portable method of body composition assessment, potentially increasing accessibility to multi-component methods.Item Field-Based Performance Tests Are Related to Body Fat Percentage and Fat-Free Mass, But Not Body Mass Index, in Youth Soccer Players(MDPI, 2018) Esco, Michael R.; Fedewa, Michael, V; Cicone, Zackary S.; Sinelnikov, Oleg A.; Sekulic, Damir; Holmes, Clifton J.; University of Alabama Tuscaloosa; University of SplitThe primary aim of this study was to determine the association between body composition and performance outcomes in youth soccer players. Twenty-five competitive male youth soccer players (age = 13.7 +/- 0.8 years, height = 167.4 +/- 9.7 cm, weight = 57.6 +/- 12.1 kg) volunteered to participate in this study. Height and weight were used to calculate body mass index (BMI). Body fat percentage (BF%) and fat-free mass (FFM) were determined with dual-energy X-ray absorptiometry. Each athlete performed the Pacer test, vertical jump, and t-test drill. Participants were predominantly normal weight (20.4 +/- 2.7 kg.m(-2)). The body composition results were 20.3 +/- 4.9% for BF% and 46.5 +/- 8.7 kg for FFM. The results of the performance tests indicated a mean standard deviation (SD) of 1418 +/- 332 m for Pacer, 57.2 +/- 7.4 cm for vertical jump, 11.6 +/- 0.7 s for t-test. Body mass index was not associated with any performance measure (r = 0.02 to -0.21, all p > 0.05). Body fat percentage was associated with the Pacer, vertical jump, and t-test (r = -0.62, -0.57, 0.61, respectively; all p < 0.01) and remained after accounting for BMI. Fat-free mass was only significantly related to t-test (r = -0.43, p < 0.01). However, after controlling for BMI, FFM was related to all three performance tests. Body fat percentage and FFM are associated with performance in youth soccer players, with stronger relationships reported in the former metric. The findings highlight the need for accurate body composition measurements as part of an assessment battery in young athletes.Item Generalized Equations for Predicting Percent Body Fat from Anthropometric Measures Using a Criterion Five-Compartment Model(Lippincott Williams & Wilkins, 2021) Cicone, Zackary S.; Nickerson, Brett S.; Choi, Youn-Jeng; Holmes, Clifton J.; Hornikel, Bjoern; Fedewa, Michael, V; Esco, Michael R.; Shenandoah University; University of Alabama Tuscaloosa; Texas A&M International University; Ewha Womans University; Washington University (WUSTL)Introduction: Anthropometric-based equations are used to estimate percent body fat (%BF) when laboratory methods are impractical or not available. However, because these equations are often derived from two-compartment models, they are prone to error because of the assumptions regarding fat-freemass composition. The purpose of this study was to develop a new anthropometric-based equation for the prediction of%BF, using a five-compartment (5C) model as the criterion measure. Methods: A sample of healthy adults (52.2% female; age, 18 to 69 yr; body mass index, 15.7 to 49.5 kg.m(-2)) completed hydrostatic weighing, dual-energy x-ray absorptiometry, and bioimpedance spectroscopy measurements for calculation of 5C%BF (%BF5C), as well as skinfolds and circumferences.%BF5C was regressed on anthropometric measures using hierarchical variable selection in a random sample of subjects (n = 279). The resulting equation was cross-validated in the remaining participants (n = 78). New model performance was also comparedwith several common anthropometric-based equations. Results: The new equation [%BFNew = 6.083 + (0.143 x SSnew) - (12.058 x sex) - (0.150 x age) - (0.233 x body mass index) + (0.256 x waist) + (0.162 x sex x age)] explained a significant proportion of variance in %BF5C (R-2 = 0.775, SEE = 4.0%). Predictors included sum of skinfolds (SSnew, midaxillary, triceps, and thigh) and waist circumference. The new equation cross-validated well against %BF5C when compared with other existing equations, producing a large intraclass correlation coefficient (0.90), small mean bias and limits of agreement (0.4% +/- 8.6%), and small measures of error (SEE = 2.5%). Conclusions: %BFNew improved on previous anthropometric-based equations, providing better overall agreement and less error in %BF estimation. The equation described in this study may provide an accurate estimate of %BF5C in healthy adults when measurement is not practical.Item Heart-Rate Variability Recording Time and Performance in Collegiate Female Rowers(Human Kinetics, 2021) Sherman, Sara R.; Holmes, Clifton J.; Hornikel, Bjoern; MacDonald, Hayley, V; Fedewa, Michael, V; Esco, Michael R.; University of Alabama Tuscaloosa; University of Illinois Chicago; University of Illinois Chicago HospitalPurpose: To assess the agreement of the root mean square of successive R-R interval (RMSSD) values when recorded immediately upon waking to values recorded later in the morning prior to practice, and to determine the associations of the RMSSD recordings with performance outcomes in female rowers. Methods: A total of 31 National Collegiate Athletic Association Division I rowers were monitored for 6 consecutive days. Two seated RMSSD measurements were obtained on at least 3 mornings using a smartphone-based photoplethysmography application. Each 1-minute RMSSD measure was recorded following a 1-minute stabilization period. The first (T1) measurement occurred at the athlete's home following waking, while the second (T2) transpired upon arrival at the team's boathouse immediately before practice. From the measures, the RMSSD mean and coefficient of variation were calculated. Two objective performance assessments were conducted on an indoor rowing ergometer on separate days: 2000-m time trial and distance covered in 30 minutes. Interteam rank was determined by the coaches, based on subjective and objective performance markers. Results: The RMSSD mean (intraclass correlation coefficient = .82; 95% CI,.63 to .92) and RMSSD coefficient of variation (intraclass correlation coefficient = .75; 95% CI,.48 to .88) were strongly correlated at T1 and T2, P < .001. The RMSSD mean at T1 and T2 was moderately associated with athlete rank (r = -.55 and r = -.46, respectively), 30-minute distance (r = .40 and r = .41, respectively), and 2000 m at T1 (r = -.37), P < .05. No significant correlations were observed for the RMSSD coefficient of variation. Conclusion: Ultrashort RMSSD measurements taken immediately upon waking show very strong agreement with those taken later in the morning, at the practice facility. Future research should more thoroughly investigate the relationship between specific performance indices and the RMSSD mean and coefficient of variation for female collegiate rowers.Item Hemodynamic Responses to Resistance Exercise with Blood Flow Restriction Using a Practical Method Versus a Traditional Cuff-Inflation System(MDPI, 2022) Winchester, Lee J.; Blake, Morgan T.; Fleming, Abby R.; Aguiar, Elroy J.; Fedewa, Michael, V; Esco, Michael R.; Earley, Ryan L.; University of Alabama TuscaloosaThe aim of this study was to examine the potential differences in acute hemodynamic responses and muscular performance outcomes following resistance exercise between traditional blood flow restriction (TRA(BFR)) and a novel band tissue flossing method (BTFBFR). METHODS: Fifteen healthy young adults (23.27 +/- 2.69 years) visited the lab for three sessions (>= 72 h apart). Each session's exercise consisted of three sets of 20 maximum-effort seated leg extensions and flexions with one of three conditions: control (CON), TRA(BFR) (50% limb occlusion pressure (LOP)), or BTFBFR. During TRA(BFR) and BTFBFR sessions, occlusion was applied immediately prior to exercise and removed immediately after. Heart rate was collected prior to exercise, after onset of occlusion, immediately after exercise, and one-minute after removal of occlusion. Ultrasonography was performed prior to, and at least 30 s after, occlusion. RESULTS: BTFBFR caused greater reductions in arterial distance (14.28%, p = 0.010) and arterial area (28.43%, p = 0.020) than TRA(BFR). BTFBFR was able to significantly reduce arterial flow below pre-occlusion values, while TRA(BFR) did not. Both conditions caused significant elevations in heart rate following occlusion (TRA(BFR): +4.67 bpm, p = 0.046 and BTFBFR: +6.07 bpm, p = 0.034), immediately post-exercise (TRA(BFR): +56.93 bpm, p < 0.001 and BTFBFR: +52.79 bpm, p < 0.001) and one-minute post-exercise (TRA(BFR): +15.71, p = 0.003 and BTFBFR: +14.57, p < 0.001). Only BTFBFR caused significant reductions in performance as measured by average power per repetition. CONCLUSIONS: BTFBFR causes a more exaggerated decrease in arterial blood flow as well as muscular power when compared to traditional TRA(BFR) at 50% of LOP.Item Improvements in skeletal muscle fiber size with resistance training are age-dependent in older adults: a systematic review and meta-analysis(American Psyiological Society, 2020) Straight, Chad R.; Fedewa, Michael, V; Toth, Michael J.; Miller, Mark S.; University of Massachusetts Amherst; University of Alabama Tuscaloosa; University of VermontAs studies examining the hypertrophic effects of resistance training (RT) at the cellular level have produced inconsistent results, we performed a systematic review and meta-analysis to investigate muscle fiber size before and after a structured RT intervention in older adults. A random-effects model was used to calculate mean effect size (ES) and 95% confidence intervals (CI). Thirty-five studies were included (age range: 59.0-88.5 yr), and 44 and 30 effects were used to estimate RT impact on myosin heavy chain (MHC) I and II fiber size. RT produced moderate-to-large increases in MHCI (ES = +0.51, 95%Cl +0.31 to +0.71; P < 0.001) and II (HS = +0.81. 95%CI +0.56 to +1.05; P < 0.001) fiber size, with men and women having a similar response. Age was negatively associated with change in muscle fiber size for both fiber types (MHCI: R-2 = 0.11, = -0.33, P = 0.002; MHCII: R-2 = 0.10. beta = -0.32, beta = 0.04), indicating a less robust hypertrophic response as age increases in older adults. Unexpectedly, a higher training intensity (defined as percentage of one-repetition maximum) was associated with a smaller increase in MIIC II fiber size (R-2 = 15.09%, beta = -0.39, P = 0.01). Notably. MIIC II fiber subtypes (IIA, IIX, IIAX) were examined less frequently, but RT improved their size. Overall, our findings indicate that RT induces cellular hypertrophy in older adults, although the effect is attenuated with increasing age. In addition, hypertrophy of MHC II fibers was reduced with higher training intensity, which may suggest a failure of muscle fibers to hypertrophy in response to high loads in older adults.Item Vagally Derived Heart Rate Variability and Training Perturbations With Menses in Female Collegiate Rowers(Human Kinetics, 2022) Sherman, Sara R.; Holmes, Clifton J.; Demos, Alexander P.; Stone, Tori; Hornikel, Bjoern; MacDonald, Hayley, V; Fedewa, Michael, V; Esco, Michael R.; University of Alabama Tuscaloosa; University of Illinois Chicago; University of Illinois Chicago Hospital; Washington University (WUSTL); Yale UniversityIntroduction: The parasympathetically derived marker of heart rate variability, root mean square of successive R-R differences (RMSSD), and the daily fluctuations as measured by the coefficient of variation (RMSSDCV) may be useful for tracking training adaptations in athletic populations. These vagally derived markers of heart rate variability may be especially pertinent when simultaneously considering a female athlete's menstrual cycle. Purpose: The purpose of this study was to observe the perturbations in RMSSDcv, while considering RMSSD, across a season in the presence and absence of menses with training load in female collegiate rowers. Methods: Thirty-six (20 [1] y, 25.6 [3.4] kg.m(-2)) National Collegiate Athletic Association Division female rowers were monitored for 18 consecutive weeks across a full season. Seated, ultrashortened RMSSD measurements were obtained by the rowers on at least 3 mornings per week using a smartphone photoplethysmography device. Following the RMSSD measurement, athletes indicated the presence or absence of menstruation within the application. Individual meters rowed that week and sessions rate of perceived exertion were obtained to quantify training load. Results: Longitudinal mixedeffects modeling demonstrated a significant effect of menses and time, while also considering RMSSD, such that those who were on their period had a significantly greater RMSSDcv than those who were not (11.2% vs 7.5%, respectively; P < .001). These changes were independent of meters rowed, sessions rate of perceived exertion, body mass index, birth-control use, and years of rowing experience, which were all nonsignificant predictors of RMSSDCgV (P > .05). Conclusion: The presence of menses appears to significantly impact RMSSDCV when also considering RMSSD, which may allow coaches to consider individualized training plans accordingly.