Browsing by Author "Rodriguez, Christian (TTU)"
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Item Assessing the reliability and cross-sectional and longitudinal validity of fifteen bioelectrical impedance analysis devices(2022) Siedler, Madelin R (TTU); Rodriguez, Christian (TTU); Stratton, Matthew T (TTU); Harty, Patrick S (TTU); Keith, Dale S (TTU); Green, Jacob J (TTU); Boykin, Jake R (TTU); White, Sarah J (TTU); Williams, Abegale D (TTU); DeHaven, Brielle (TTU); Tinsley, Grant M (TTU)The purpose of this investigation was to expand upon the limited existing research examining the test–retest reliability, cross-sectional validity and longitudinal validity of a sample of bioelectrical impedance analysis (BIA) devices as compared with a laboratory four-compartment (4C) model. Seventy-three healthy participants aged 19–50 years were assessed by each of fifteen BIA devices, with resulting body fat percentage estimates compared with a 4C model utilising air displacement plethysmography, dual-energy X-ray absorptiometry and bioimpedance spectroscopy. A subset of thirty-seven participants returned for a second visit 12–16 weeks later and were included in an analysis of longitudinal validity. The sample of devices included fourteen consumer-grade and one research-grade model in a variety of configurations: hand-to-hand, foot-to-foot and bilateral hand-to-foot (octapolar). BIA devices demonstrated high reliability, with precision error ranging from 0·0 to 0·49 %. Cross-sectional validity varied, with constant error relative to the 4C model ranging from −3·5 (SD 4·1) % to 11·7 (SD 4·7) %, standard error of the estimate values of 3·1–7·5 % and Lin’s concordance correlation coefficients (CCC) of 0·48–0·94. For longitudinal validity, constant error ranged from −0·4 (SD 2·1) % to 1·3 (SD 2·7) %, with standard error of the estimate values of 1·7–2·6 % and Lin’s CCC of 0·37–0·78. While performance varied widely across the sample investigated, select models of BIA devices (particularly octapolar and select foot-to-foot devices) may hold potential utility for the tracking of body composition over time, particularly in contexts in which the purchase or use of a research-grade device is infeasible.Item Chronic Thermogenic Dietary Supplement Consumption: Effects on Body Composition, Anthropometrics, and Metabolism(2023) Siedler, Madelin R. (TTU); Rodriguez, Christian (TTU); White, Sarah J. (TTU); Tinoco, Ethan (TTU); DeHaven, Brielle (TTU); Brojanac, Alexandra (TTU); LaValle, Christian (TTU); Rasco, Jaylynn (TTU); Taylor, Lem W.; Tinsley, Grant M. (TTU)Multi-ingredient thermogenic supplements can acutely increase resting energy expenditure (REE) and subjective energy. However, less is understood about the effects of chronic consumption on body composition, metabolism, and subjective variables such as mood, sleep quality, and eating behaviors. Fifty-two healthy, exercise-trained participants (50% female; mean ± SD age: 23.5 ± 3.0 years; body fat percentage: 27.3 ± 8.0%) were randomized 2:2:1 to take a whey protein supplement alone (PRO; n = 20), in combination with a thermogenic supplement (PRO + FB; n = 19), or no supplement at all (CON; n = 13) for four weeks. Body composition, anthropometric, metabolic, hemodynamic, and subjective outcomes were collected before and after the intervention. Greater changes in REE occurred in PRO + FB as compared to CON (111.2 kcal/d, 95% CI 2.4 to 219.9 kcal/d, p = 0.04), without significant differences between PRO and CON (42.7 kcal/d, 95% CI −65.0 to 150.3 kcal/d, p = 0.61) or between PRO + FB and PRO (68.5 kcal/d, 95% CI −28.3, 165.3, p = 0.21). No changes in hemodynamic outcomes (blood pressure and heart rate) were observed. In exercising adults, four weeks of supplementation with protein and a multi-ingredient thermogenic product maintained fasted REE as compared to no supplementation, for which a decrease in REE was observed, without differential effects on body composition, anthropometrics, or subjective variables.Item Evaluation of novel beverage formulations for hydration enhancement in humans(2023) Tinsley, Grant M. (TTU); Siedler, Madelin R. (TTU); Rodriguez, Christian (TTU); Harty, Patrick S. (TTU); Stratton, Matthew T. (TTU); White, Sarah J. (TTU); Keith, Dale S. (TTU); Green, Jacob J. (TTU); Boykin, Jake R. (TTU); Williams, Abegale D. (TTU); DeHaven, Brielle (TTU); Brojanac, Alexandra (TTU); Tinoco, Ethan (TTU)This study evaluated the influence of novel beverage formulations on bioimpedance- and urine-based hydration markers. Thirty young healthy adults (n=16 females, n=14 males; age: 23.2±3.7 years; BMI: 24.3±3.3 kg/m2) participated in a randomized, double-blind, placebo-controlled, crossover study. Participants completed three conditions with baseline bioimpedance, urine, and body mass assessments, followed by ingestion of one liter of a test beverage over a 30-minute period. The three beverages were: active hydration formulation in still (AFstill) or sparkling (AFspark) water and a still water control. The active formulations were identical in concentrations of alpha-cyclodextrin and complexing agents. Following beverage ingestion, bioimpedance assessments were performed every 15 minutes for two hours, followed by final urinary and body mass assessments. The primary bioimpedance outcomes were phase angle at 50 kHz, resistance of the extracellular compartment (R0), and resistance of the intracellular compartment (Ri). Data were analyzed using linear mixed effects models, Friedman tests, and Wilcoxon tests. Statistically significant changes in phase angle values were observed at 30 (p=0.004) and 45 minutes (p=0.024) following the initiation of beverage ingestion in the AFstill condition as compared to the reference model (i.e., control condition at baseline). Although differences between conditions were not statistically significant at later time points, the data were consistent with AFstill having greater elevations in phase angle throughout the monitoring period. At the 30-minute time point only, statistically significant differences in R0 for AFspark (p<0.001) and in Ri for AFstill (p=0.008) were observed. When averaged across post-ingestion time points, there was a trend (p=0.08) for Ri differences between conditions. The net fluid balance was greater than zero, indicating retention of ingested fluid, for AFstill (p=0.02) and control (p=0.03), with a trend for AFspark (p=0.06). In conclusion, an active formulation containing alpha-cyclodextrin in still water demonstrated potential benefits for enhancing hydration markers in humans.Item Improved precision of 3-dimensional optical imaging for anthropometric measurement using non-rigid avatar reconstruction and parameterized body model fitting(2023) Tinsley, Grant M. (TTU); Harty, Patrick S. (TTU); Siedler, Madelin R. (TTU); Stratton, Matthew T. (TTU); Rodriguez, Christian (TTU)Background: Three-dimensional optical imaging for digital anthropometry and body composition estimation is increasingly available to health professionals and individual consumers. The purpose of the present analysis was to examine the precision of a scanner that employs non-rigid avatar reconstruction and parameterized body model fitting. Methods: Sixty-nine healthy adults (37 F, 32 M; [mean ±SD] age: 24.1±5.5 y; height: 169.2±13.9 cm; BMI: 26.0±5.2 kg/m2) were evaluated through duplicate scans using a second-generation prototype three-dimensional optical scanner. Test-retest precision was established using the intraclass correlation coefficient (ICC), root-mean-square coefficient of variation (RMS-%CV), precision error (PE), and least significant change. Results: Across 21 non-ankle body circumferences, PE ranged from 0.4 to 0.8 cm, RMS-%CV ranged from 0.4 to 1.4%, and ICC values were 0.975–0.999. Compared to the first-generation scanner (PE: 0.8–1.0 cm; RMS-%CV: 0.8–1.2%), the errors of waist and hip circumferences were reduced by half (PE: 0.4–0.5 cm, RMS-%CV: 0.4–0.6%). Estimated body fat percentage also demonstrated very high reliability (PE: 0.2%, RMS-%CV: 0.7%, ICC: 0.999). Conclusions: These findings support the improved precision of a second-generation scanner reconstructing a non-rigid avatar subject and parameterized body model fitting and demonstrate the low measurement error that is achievable with this technology.Item Liposomal Mineral Absorption: A Randomized Crossover Trial(2022) Tinsley, Grant M (TTU); Harty, Patrick S (TTU); Stratton, Matthew T (TTU); Siedler, Madelin R (TTU); Rodriguez, Christian (TTU)Multivitamin/mineral (MVM) supplements are one of the most popular dietary supplement categories. The purpose of this analysis was to determine if a novel liposomal delivery mechanism improves mineral absorption from an MVM product. In a randomized crossover trial, 25 healthy participants (12 females, 13 males) completed two testing sessions in which blood samples were collected at baseline and 2, 4, and 6 h following the ingestion of either a liposomal MVM or a nutrient-matched standard MVM. Analysis of MVM products indicated an elemental iron content of 9.4 and 10.1 mg (~50% U.S. FDA Daily Value) and an elemental magnesium content of 22.0 and 23.3 mg (~5% U.S. FDA Daily Value) in the liposomal and standard MVM products, respectively. Blood samples were analyzed for concentrations of iron and magnesium using colorimetric assays. Changes in mineral concentrations were analyzed using linear mixed models, and pharmacokinetic parameters were compared between conditions. For iron, statistically significant condition × time interactions were observed for percent change from baseline (p = 0.002), rank of percent change from baseline (p = 0.01), and raw concentrations (p = 0.02). Follow-up testing indicated that the liposomal condition exhibited larger changes from baseline than the standard MVM condition at 4 (p = 0.0001; +14.3 ± 18.5% vs. −6.0 ± 13.1%) and 6 h (p = 0.0002; +1.0 ± 20.9% vs. −21.0 ± 15.3%) following MVM ingestion. These changes were further supported by a 50% greater mean incremental area under the curve in the liposomal condition (33.2 ± 30.9 vs. 19.8 ± 19.8 mcg/dL × 6 h; p = 0.02, Cohen’s d effect size = 0.52). In contrast, no differential effects for magnesium absorption were observed. In conclusion, iron absorption from an MVM product is enhanced by a liposomal delivery mechanism.Item Predicting adaptations to resistance training plus overfeeding using bayesian regression: A preliminary investigation(2021) Smith, Robert W. (TTU); Harty, Patrick S. (TTU); Stratton, Matthew T. (TTU); Rafi, Zad; Rodriguez, Christian (TTU); Dellinger, Jacob R. (TTU); Benavides, Marqui L. (TTU); Johnson, Baylor A. (TTU); White, Sarah J. (TTU); Williams, Abegale D. (TTU); Tinsley, Grant M. (TTU)Relatively few investigations have reported purposeful overfeeding in resistance-trained adults. This preliminary study examined potential predictors of resistance training (RT) adaptations during a period of purposeful overfeeding and RT. Resistance-trained males (n = 28; n = 21 completers) were assigned to 6 weeks of supervised RT and daily consumption of a high-calorie protein/carbohydrate supplement with a target body mass (BM) gain of ≥0.45 kg·wk−1 . At baseline and post-intervention, body composition was evaluated via 4-component (4C) model and ultrasonography. Additional assessments of resting metabolism and muscular performance were performed. Accelerometry and automated dietary interviews estimated physical activity levels and nutrient intake before and during the intervention. Bayesian regression methods were employed to examine potential predictors of changes in body composition, muscular performance, and metabolism. A simplified regression model with only rate of BM gain as a predictor was also developed. Increases in 4C whole-body fat-free mass (FFM; (mean ± SD) 4.8 ± 2.6%), muscle thickness (4.5 ± 5.9% for elbow flexors; 7.4 ± 8.4% for knee extensors), and muscular performance were observed in nearly all individuals. However, changes in outcome variables could generally not be predicted with precision. Bayes R2 values for the models ranged from 0.18 to 0.40, and other metrics also indicated relatively poor predictive performance. On average, a BM gain of ~0.55%/week corresponded with a body composition score ((∆FFM/∆BM)*100) of 100, indicative of all BM gained as FFM. However, meaningful variability around this estimate was observed. This study offers insight regarding the complex interactions between the RT stimulus, overfeeding, and putative predictors of RT adaptations.Item The influence of caffeinated and non-caffeinated multi-ingredient pre-workout supplements on resistance exercise performance and subjective outcomes(2022) Stratton, Matthew T. (TTU); Siedler, Madelin R. (TTU); Harty, Patrick S. (TTU); Rodriguez, Christian (TTU); Boykin, Jake R. (TTU); Green, Jacob J. (TTU); Keith, Dale S. (TTU); White, Sarah J. (TTU); DeHaven, Brielle (TTU); Williams, Abegale D. (TTU); Tinsley, Grant M. (TTU)Background: There is substantial consumer and practitioner interest in an emerging supplement class known as multi-ingredient pre-workout supplements (MIPS), largely due to their prevalence in resistance training communities as well as research findings demonstrating the ergogenic impact of caffeine on muscular performance. However, limited research has examined the potential efficacy of non-caffeinated MIPS, despite their growing popularity among those who are caffeine-sensitive or who train later in the day. Methods: Twenty-four resistance-trained college-aged males (n = 12) and females (n = 12) completed three visits in which they ingested either a caffeinated MIPS (C), an otherwise identical non-caffeinated MIPS (NC), or placebo in a double-blind, counterbalanced, crossover fashion. Squat isometric peak force (PFiso), rate of force development (RFD), and isokinetic performance were assessed. Upper and lower body maximal muscular strength and endurance were evaluated using the bench press and leg press, respectively. Visual analog scales for energy, focus, and fatigue were completed five times throughout the testing protocol. The effects of supplementation and biological sex on all variables were examined using linear mixed effects models. Results: Significantly greater PFiso was observed in both C (b: 0.36 transformed units [0.09, 0.62]) and NC (b: 0.32 transformed units [95% CI: 0.05, 0.58]) conditions, relative to placebo. Early RFD (RFD50) may have been higher with supplementation, particularly in females, with no effects for late RFD (RFD200) or peak RFD. In addition, increases in subjective energy after supplement ingestion were noted for C, but not NC. No effects of supplementation on traditional resistance exercise performance or isokinetic squat performance were observed, other than a lower leg press one-repetition maximum for males in the NC condition. Conclusions: These data indicate that acute ingestion of either a caffeinated or non-caffeinated pre-workout formulation improved maximal force production during an isometric squat test but did not provide additional benefit to leg press, bench press, or isokinetic squat performance over placebo, within the context of a laboratory environment. The consumption of a caffeinated, but not non-caffeinated, MIPS increased subjective ratings of energy over placebo when assessed as part of a testing battery.