Allyn Byars

Creatine supplementation patterns and perceived effects in select division I collegiate athletes.

ObjectiveTo describe patterns of creatine use in select Division I collegiate athletes based on recommended dosages according to body weight. Further, to report the perceived effects noted with creatine supplementation. DesignAnonymous open-ended self-report descriptive questionnaire. SettingNational Collegiate Athletic Association Division I institution. ParticipantsTwo-hundred and nineteen male and female collegiate athletes representing eight varsity sports. Main Outcome Measure(s)An open-ended questionnaire was administered to determine patterns of creatine use during the loading and maintenance phases of this nutritional supplement. In addition, perceived positive, negative, and no effects associated with creatine usage patterns were determined from athlete responses on this self-report measure. ResultsConsidering this select group of collegiate athletes, highly variable patterns of creatine supplementation were noted for loading/maintenance phases based on recommended dosages/days and body weight. Of the 219 athletes surveyed, 90 (41%) reported using creatine, while creatine supplementation was more prevalent among men than women. Creatine users (80 athletes, 89%) reporting perceived positive effects were primarily at or below recommended dosages for the loading phase but above recommended dosages in the maintenance phase. Creatine users (34 athletes, 38%) reporting perceived negative effects were primarily at or below recommended dosages in the loading phase but noticeably above recommended dosages in the maintenance phase. Ironically, all creatine users who reported negative side effects also reported positive effects. Creatine users (10 athletes, 11%) reporting no effects were below recommended loading dosages but above recommended maintenance dosages. ConclusionsThe perceived positive effects noted support current research (strength/weight gains), while the perceived negative effects (cramping/gastrointestinal distress) were consistent with anecdotal reports surrounding creatine supplementation. Apparently, collegiate athletes in this study are in need of education regarding the proper use of creatine supplementation. Additional studies are needed to ascertain creatine supplementation patterns of collegiate athletes in various settings.

The effects of creatine monohydrate supplementation with and without D-pinitol on resistance training adaptations.

Kerksick, CM, Wilborn, CD, Campbell, WI, Harvey, TM, Marcello, BM, Roberts, MD, Parker, AG, Byars, AG, Greenwood, LD, Almada, AL, Kreider, RB, and Greenwood, M. The effects of creatine monohydrate supplementation with and without D-pinitol on resistance training adaptations. J Strength Cond Res 23(9): 2673-2682, 2009-Coingestion of D-pinitol with creatine (CR) has been reported to enhance creatine uptake. The purpose of this study was to evaluate whether adding D-pinitol to CR affects training adaptations, body composition, whole-body creatine retention, and/or blood safety markers when compared to CR ingestion alone after 4 weeks of resistance training. Twenty-four resistance trained males were randomly assigned in a double-blind manner to creatine + pinitol (CRP) or creatine monohydrate (CR) prior to beginning a supervised 4-week resistance training program. Subjects ingested a typical loading phase (i.e., 20 g/d−1 for 5 days) before ingesting 5 g/d−1 the remaining 23 days. Performance measures were assessed at baseline (T0), week 1 (T1), and week 4 (T2) and included 1 repetition maximum (1RM) bench press (BP), 1RM leg press (LP), isokinetic knee extension, and a 30-second Wingate anaerobic capacity test. Fasting blood and body composition using dual-energy x-ray absorptiometry (DEXA) were determined at T1 and T3. Data were analyzed by repeated measures analysis of variance (ANOVA). Creatine retention increased (p < 0.001) in both groups as a result of supplementation but was not different between groups (p > 0.05). Significant improvements in upper- and lower-body strength and body composition occurred in both groups. However, significantly greater increases in lean mass and fat-free mass occurred in the CR group when compared to CRP (p <0.05). Adding D-pinitol to creatine monohydrate does not appear to facilitate further physiological adaptations while resistance training. Creatine monohydrate supplementation helps to improve strength and body composition while resistance training. Data from this study assist in determining the potential role the addition of D-pinitol to creatine may aid in facilitating training adaptations to exercise.

The Effectiveness of a Pre-Exercise Performance Drink (PRX) on Indices of Maximal Cardiorespiratory Fitness

This study examined the effectiveness of a pre-exercise drink (PRX) called EM·PACT on indices of maximal cardiorespiratory fitness. Twenty-four males (n = 12) and females (n = 12) ages 18–24 years (20.25 + 1.42), volunteered as subjects. Each subject performed two randomized trials of a VO2max treadmill test within a week of each other. Subjects in this randomized, placebo controlled, counter balanced, crossover design, ingested either a placebo (water) or PRX 20 minutes before each exercise bout. VO2max and time to exhaustion (Time) during graded exercise testing were evaluated. Using paired samples t-tests, significantly greater mean values were found in VO2max and Time for the PRX trial compared to the placebo trial (p < .05). Results indicate that indices of cardiorespiratory fitness; specifically VO2max and Time are enhanced by ingestion of PRX prior to exercise testing. The combined results of this investigation may provide meaningful practical applications for coaches and athletes alike regarding ergogenic hydration options.

The effects of IQPLUS Focus on cognitive function, mood and endocrine response before and following acute exercise

BackgroundPhosphatidylserine (PS) is a phospholipid found in cell membranes of most animals and plants. PS has been shown to reduce stress and increase performance in runners, cyclists and golfers. The purpose of this study was to investigate the effects of a PS containing formulation on cognitive function, mood and endocrine response before and after intense resistance exercise.Methods18 lower body, resistance trained, college aged males ingested 14 days of supplement (IQPLUS Focus, providing 400 mg of soy-derived PS) and a Placebo (PL), in a randomized, double-blind, placebo controlled, cross-over manner. Following 14 days of supplementation, participants performed an acute bout of lower body resistance training. Mood (Profile of Mood States, POMS) and cognitive function (Serial Subtraction Test, SST) were measured prior to, 5 minutes after, and 60 minutes after exercise. Venous blood samples were collected prior to, and 5, 15, 25, 40 and 60 minutes after exercise. Blood samples were analyzed for plasma cortisol and testosterone. Data were analyzed using repeated measures ANOVA.ResultsPS supplementation significantly reduced the time needed for a correct calculation on the SST by 20% (reduced by 1.27 s per calculation; PL: 6.4 s, PS: 5.13 s; p = 0.001), and reduced the total amount of errors by 39% (PL: 1.28 + .69, PS: .78 + .27, p = 0.53), and increased the amount of correct calculations by 13% (PL: 22.1 + 2.24, PS: 24.9 + 1.52, p = 0.07) prior to or in response to exercise compared to PL. Following exercise, there was no difference in SST scores between PS and PL. There were no significant changes in regards to mood or endocrine response to exercise as a result of PS supplementation.ConclusionPS supplementation significantly increased cognitive function prior to exercise. Improved cognitive function could benefit athletes and non-athletes alike. PS did not appear to affect mood or endocrine response prior to or following resistance exercise.

Centralization of symptoms and lumbar range of motion in patients with low back pain

This quasi-experimental repeated measures study examined the relationship between centralization of symptoms and lumbar flexion and extension range of motion (ROM) in patients with low back pain. Rapid and lasting changes in lumbar ROM have been noted with centralization of symptoms. However, no study has objectively measured the changes in lumbar ROM occurring with centralization. Forty-two adult subjects (mean age, 45.68 years; SD=15.76 years) with low back pain and associated lower extremity symptoms were followed by McKenzie trained physical therapists. Subjects’ lumbar ROM was measured at the beginning and end of each patient visit by using double inclinometers, and pain location was documented. Subjects were grouped as 1) centralized, 2) centralizing, or 3) noncentralized for comparisons of symptom and ROM changes. Data were analyzed by using multivariate analysis of variance and one-way analysis of variance. Significance was set at 0.05. A significant difference was found between initial and final mean extension ROM in the centralized and centralizing groups (p=0.003). No significant difference was found in the noncentralized group (p<0.05). Subjects (n=23) who demonstrated a change in pain location during the initial visit also showed a significant (p<0.001) change in extension ROM, whereas patients with no change in pain location (n=19) did not (p=0.848). Lumbar extension ROM increased as centralization occurred.

Comparison of two stretching protocols on lumbar spine extension

Purpose: To compare range of motion (ROM) outcomes of repeated extension versus static stretching of the lumbar spine in healthy adults. Methods: 101 subjects volunteered and were randomly assigned to 1of 3 groups: repeated extension (Group A, n =3 3), static stretching (Group B, n =3 6), or control (Group C, n =3 2). Double inclinometers were used to measure lumbar extension ROM (prone). Measurements were taken at baseline, 4 weeks, and 8 weeks. MANOVA assessed equivalence of the 3 groups for age and initial ROM; chi-square testing assessed gender differences. ROM data were assessed using General Linear Mixed Model Analysis. Alpha was set at 0.05. Results: Both methods of stretching increased lumbar extension ROM at 4 and 8 weeks. The repeated stretching group increased ROM more than the static group. Group A differences were significant comparing 8 to 4 weeks and to baseline. Group B differences were also significant comparing 8 to 4 weeks and to baseline. At 8 weeks, only group A was significantly different than the control group. Conclusion: Repeated and static stretching improved lumbar extension ROM when compared to no stretching. However, repeated extension when compared to static stretching showed greater gains in lumbar extension ROM after 8 weeks of stretching.

The effects of alpha-glycerylphosphorylcholine, caffeine or placebo on markers of mood, cognitive function, power, speed, and agility

Background Alpha-glycerylphosphorylcholine (Alpha-GPC) and caffeine supplementation have been shown to improve mental and physical performance. Alpha-GPC administration increases the release of the neurotransmitter acetylcholine and facilitates learning and memory. In athletes, Alpha-GPC supplementation prevents exerciseinduced reductions in choline levels, increases endurance performance and growth hormone secretion. Caffeine has been shown to increase mental focus, acuity and athletic performance, however, contributes to a nervous or anxious feeling. The purpose of this study was to measure the acute effects of Alpha-GPC supplementation in comparison to caffeine or placebo on mood, cognitive function, and physiological performance.

The influence of a pre-exercise sports drink (PRX) on factors related to maximal aerobic performance

BackgroundPre-exercise sports drinks (PRX) are commonly used as ergogenic aids in athletic competitions requiring aerobic power. However, in most cases, claims regarding their effectiveness have not been substantiated. In addition, the ingredients in PRX products must be deemed acceptable by the athletic governing bodies that regulate their use in training and competition. The purpose of this study was to examine the effects of a modified PRX formulation (known as EM·PACT™) from earlier investigations on factors related to maximal aerobic performance during a graded exercise test. The modification consisted of removing creatine to meet the compliance standards set forth by various athletic organizations that regulate the use of nutritional supplements.MethodsTwenty-nine male and female college students varying in levels of aerobic fitness participated in a randomized crossover administration of PRX (containing 14 g/serving of fructose, medium-chain triglycerides, and amino acids mixed with 8 oz. of water) and placebo (PL) 30 minutes prior to performing a treadmill test with approximately one week separation between the trials. VO2max, maximal heart rate (HR), time to exhaustion (Time), and percentage estimated non-protein fat substrate utilization (FA) during two a priori submaximal stages of a graded exercise testing were evaluated.ResultsThe VO2max mean value of the PRX trial was significantly greater than the PL trial (P < 0.01). The mean value for Time was also observed to be greater for the PRX trial compared to PL (P < 0.05). Additionally, percentage of FA during submaximal stages of the exercise test was greater for PRX trial in comparison to PL (P < 0.01).ConclusionsThe modified PRX formulation utilized in this investigation supports the findings of the previous investigation and its efficacy for enhancing indices of aerobic performance (specifically VO2max, Time, & FA) during graded exercise testing.

Effects of G-Trainer, Cycle Ergometry, and Stretching on Physiological and Psychological Recovery From Endurance Exercise

Abstract West, AD, Cooke, MB, LaBounty, PM, Byars, AG, and Greenwood, M. Effects of G-trainer, cycle ergometry, and stretching on physiological and psychological recovery from endurance exercise. J Strength Cond Res 28(12): 3453–3461, 2014—The purpose of this study was to compare the effectiveness of 3 treatment modes (Anti-Gravity Treadmill [G-trainer], stationary cycling [CompuTrainer], and static stretching) on the physiological and psychological recovery after an acute bout of exhaustive exercise. In a crossover design, 12 aerobically trained men (21.3 ± 2.3 years, 72.1 ± 8.1 kg, 178.4 ± 6.3 cm, : 53.7 ± 6.3 ml·kg−1·min−1) completed a 29-km stationary cycling time trial. Immediately after the time trial, subjects completed 30 minutes of G-trainer or CompuTrainer (40% ) or static stretching exercises. A significant time effect was detected for plasma lactate (p = 0.010) and serum cortisol (p = 0.039) after exercise. No treatment or treatment by time interaction was identified for lactate or cortisol, respectively. No main effects for time, treatment, or treatment by time interaction were identified for interleukin 6 (IL-6) and tumor necrosis factor &agr; (TNF-&agr;). No differences were observed among treatments in skeletal muscle peak power output, mean power output, time to peak power, and rate to fatigue at 24 hours postexercise bout. Finally, no significant changes in mood status were observed after exercise and between treatment groups. When compared with stationary cycling and static stretching, exercise recovery performed on the G-trainer was unable to reduce systemic markers of stress and inflammation, blood lactate, or improve anaerobic performance and psychological mood states after an exhaustive bout of endurance exercise. Further research is warranted that includes individualized recovery modalities to create balances between the stresses of training and competition.

Relationship of various body composition parameters used for predicting VO2max

Results Using multiple linear regression, a model was produced where significant predictors of VO2max (p < 0.05) included estimated body fat percentage from sum of three skinfolds (p < .001) and BMI (p = .024). The generalized equation (R = .741, R2 = .549, SEE = 7.10) derived from the model to predict VO2max was: 72.32 + (-.949 × %fat from skinfolds) – (.392 × BMI). Variables excluded (p > 0.05) from the model included 6-minute walk test time, PARS, height, weight, gender, age, and percent body fat from bioelectrical impedance analysis. Conclusion It was concluded that that percent body fat and BMI are significant predictors of VO2max. Although the relationship between VO2max and the other variables examined in this study were not significant, it may have been due to the homogeneity of these parameters (e.g., age and activity levels) in the participants and the lack of the 6-minute walk test to discriminate among fitness levels in university students. However, these results demonstrate the importance of the relationship between BMI and percent body fat (estimated from skinfolds) in predicting VO2max without maximal testing. from 2008 International Society of Sports Nutrition Conference and Expo Las Vegas, NV, USA. 9–10 June 2008