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Title: Noninvasive myographical assessments following unaccustomed resistance exercise.
Creator: Boone, Carleigh, Fragala, Maren, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description: Traditionally, post-exercise muscular alterations have been examined using invasive techniques that lack the ability to single out individual muscle groups. Sonomyography, tensiomyography, and electrical impedance myography allow for noninvasive skeletal muscle assessment. This project aimed to examine changes in muscle contractility and composition that occur in the early stages of recovery following unaccustomed exercise. METHODS: Twenty-one untrained adults (21.9 (&)#177; 1.9 y) performed...
Show moreTraditionally, post-exercise muscular alterations have been examined using invasive techniques that lack the ability to single out individual muscle groups. Sonomyography, tensiomyography, and electrical impedance myography allow for noninvasive skeletal muscle assessment. This project aimed to examine changes in muscle contractility and composition that occur in the early stages of recovery following unaccustomed exercise. METHODS: Twenty-one untrained adults (21.9 (&)#177; 1.9 y) performed exercise (-) 10 (&)#215; 10 maximal eccentric knee extensions (-) with their nondominant leg. For each repetition, participants moved through 90(&)deg; range of motion at 90(&)deg;•s-1 with a passive return to the start position. Each set was separated by 60 seconds of rest. Sonomyography, tensiomyography, electrical impedance myography, and maximal isometric contractions of the knee extensors (RF (&) VL) of both legs were performed before (BL), immediately after (IP), and 24 hours post-exercise (24H). RESULTS: Peak torque and rate of torque development were unaltered in response to the eccentric protocol. Significant limb (&)#215; time interactions were noted for reactance, phase angle, and delay time of the exercised VL, and echo intensity of the exercised RF. Compared to the dominant leg, the nondominant leg displayed significantly greater changes (p (<) 0.05) in VL delay time and RF echo intensity at IP. Following exercise, bilateral alterations were identified for reactance, phase angle, maximal displacement, delay time, contraction velocity, cross-sectional area, and thickness of the RF, as well as resistance, echo intensity, cross-sectional area, and thickness of the VL. No between-sex differences were noted in response to exercise. CONCLUSIONS: In the absence of performance decrements, sonomyography, tensiomyography, and electrical impedance myography successfully detected acute changes in skeletal muscle composition and function following an acute bout of eccentric exercise in untrained men and women. While the exercised leg exhibited specific responses in delay time and echo intensity, bilateral changes are theorized to have occurred due to contralateral stabilization of the non-exercised leg. The current results suggest that different muscle actions (i.e., eccentric and isometric) promote similar consequences to muscle strength, size, echogenicity, contractility, and bioelectrical properties.
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Date Issued: 2019
Identifier: CFE0007432, ucf:52731
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007432

Title: Examining Work-To-Rest Ratios To Optimize Upper Body Sprint Interval Training.
Creator: Lamonica, Michael, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
Abstract / Description: The primary purpose of this study was to compare the metabolic influence of varying work-to-rest ratios during upper body sprint interval training (SIT). Forty-two recreationally trained men were randomized into one of three training groups [10s work bouts with two minutes of rest (10:2, n = 11) or four minutes of rest (10:4, n = 11), or 30s work bouts with four minutes of rest (30:4, n = 10)] or a control group (CON, n = 10). Participants underwent six training sessions over two weeks with...
Show moreThe primary purpose of this study was to compare the metabolic influence of varying work-to-rest ratios during upper body sprint interval training (SIT). Forty-two recreationally trained men were randomized into one of three training groups [10s work bouts with two minutes of rest (10:2, n = 11) or four minutes of rest (10:4, n = 11), or 30s work bouts with four minutes of rest (30:4, n = 10)] or a control group (CON, n = 10). Participants underwent six training sessions over two weeks with four to six 'all-out' sprints. During pre- and post-intervention visits, participants underwent a graded exercise test to determine maximal oxygen consumption (V?O2peak) and peak power output (PPO), four constant-work rate trials to determine critical power (CP), anaerobic working capacity (W'), and electromyographic fatigue threshold (EMGFT), and an upper body Wingate test to determine peak power (PP), mean power (MP), and total work (TW). Oxygen consumption and blood lactate during the Wingate test generated estimates of oxidative, glycolytic, and ATP-PCr energy system provisions. An analysis of covariance was performed on all testing measurements collected at post with the associated pre-values used as covariates. V?O2peak was greater in 30:4 (p = .007) and 10:2 (p = .036) compared to CON and PPO was greater in 30:4 than CON (p = .007). No differences were observed between groups in CP (p = .530), W' (p = .900), EMGFT (p = .692), PP (p = .692), MP (p = .290), or TW (p = .291). Relative energy contribution (p = .026) and energy expenditure (p = .019) of the ATP-PCr energy system was greater in 10:4 compared to CON. SIT protocols with larger work-to-rest ratios induce enhanced aerobic adaptions, whereas smaller work-to-rest ratios may enhance ATP-PCr utilization in the upper body over a short-term two-week intervention.
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Date Issued: 2018
Identifier: CFE0007036, ucf:51978
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007036

Title: The Effects of Phosphatidylserine on Reaction Time and Cognitive Function Following an Exercise Stress.
Creator: Wells, Adam, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, University of Central Florida
Abstract / Description: Phosphatidylserine (PS) is an endogenously occurring phospholipid that has been shown to have cognition and mood enhancing properties in humans, possibly through its role as an enzyme co-factor in cellular signal transduction. Specifically, PS has been identified as activator of classical isoforms of protein kinase C, an enzyme known to be involved in the growth and differentiation of neural cells, and is therefore thought to play a role in the protection of neurons.The purpose of this study...
Show morePhosphatidylserine (PS) is an endogenously occurring phospholipid that has been shown to have cognition and mood enhancing properties in humans, possibly through its role as an enzyme co-factor in cellular signal transduction. Specifically, PS has been identified as activator of classical isoforms of protein kinase C, an enzyme known to be involved in the growth and differentiation of neural cells, and is therefore thought to play a role in the protection of neurons.The purpose of this study was to examine the effects of supplementation with PS and caffeine on measures of cognition, reaction time and mood prior to and following an exercise stress. Twenty, healthy, resistance trained males (17) and females (3) (mean (&)#177; SD; age: 22.75 (&)#177; 3.27 yrs; height: 177.03 (&)#177; 8.44cm; weight: 78.98 (&)#177; 11.24kg; body fat%: 14.28 (&)#177; 6.6), volunteered to participate in this randomized, double-blind, placebo-controlled study. Participants were assigned to a PS group (400mg/day PS; 100mg/day caffeine, N=9) or PL (16g/day Carbs, N=11) delivered in the form of 4 candy chews identical in size, shape and color. Subjects performed an acute bout of full body resistance exercise, prior to (T1) and following 14 days of supplementation (T2). Measures of reaction time (Dynavision(&)#174; D2 Visuomotor Training Device), cognition (Serial Subtraction Test, SST), and mood (Profile of Mood States, POMS) were assessed immediately before and following resistance exercise in both T1 and T2. Data was analyzed using two-way ANCOVA and repeated measures ANOVA.Supplementation with 400mg PS and 100mg caffeine did not have a significant impact upon measures of reaction time or cognition between groups at baseline or following acute resistance exercise. However, there was a non-significant trend to the attenuation of fatigue between groups, following acute resistance exercise (p = 0.071). Interestingly, our data suggests that acute resistance exercise alone may improve cognitive function.Although more research is necessary regarding optimal dosage and supplementation duration, the current findings suggest that supplementation 400mg/day PS with 100mg/day caffeine may attenuate fatigue following acute resistance exercise. It is possible that the lack of significance may be the result of both an inhibition of the PS activated pathway and a withdrawal effect from caffeine.
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Date Issued: 2012
Identifier: CFE0004457, ucf:49325
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004457

Title: The Effects of Sprint Interval Training and Maturity Status on Metabolic and Neuromuscular Fatigue Thresholds in Adolescents.
Creator: Beyer, Kyle, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
Abstract / Description: Purpose: To examine the maturity-related differences in the adaptations to systemic and localized fatigue thresholds (FTs) in response to sprint interval training (SIT) amongst adolescent male athletes. Methods: Twenty-seven adolescent male athletes, 11-17 years of age, completed pre-testing, six weeks of SIT, and post-testing. Participants were grouped according to their number of years from peak height velocity (PHV), an estimation of somatic maturity status, into PRE (()+1.5yr) PHV groups....
Show morePurpose: To examine the maturity-related differences in the adaptations to systemic and localized fatigue thresholds (FTs) in response to sprint interval training (SIT) amongst adolescent male athletes. Methods: Twenty-seven adolescent male athletes, 11-17 years of age, completed pre-testing, six weeks of SIT, and post-testing. Participants were grouped according to their number of years from peak height velocity (PHV), an estimation of somatic maturity status, into PRE ((<)-1.5yr), PERI (between -1.5 to +1.5yr) and POST ((>)+1.5yr) PHV groups. Each testing session consisted of a ramp exercise protocol on a cycle ergometer. During the protocol, three systemic FTs, gas exchange threshold, ventilatory threshold, and respiratory compensation point were calculated from gas exchange and ventilatory parameters. Also, three localized FTs, neuromuscular fatigue threshold (NFT), deoxyhemoglobin breakpoint (HHbBP), and oxygenation deflection point (OxDP) were calculated from electromyography (NFT) and near-infrared spectroscopy signals (HHbBP and OxDP) from the vastus lateralis of both legs. Data were plotted versus oxygen consumption and 30-second moving averages were calculated. All FTs were determined using the maximal distance method. Localized FTs were averaged between the two legs. The six weeks of SIT consisted of repeated 20-second (")all-out(") sprints on a cycle ergometer against a load equivalent to 7.5% of body mass with 4-minute rest periods. Maturity-related differences to the adaptations to SIT were assessed with mixed-factorial ANOVA and magnitude-based inferences. Results: During training, POST and PERI completed significantly greater relative work (p=0.003 and p=0.002, respectfully) and peak power (p=0.025 and p=0.023, respectfully) per session than PRE. Furthermore, POST achieved significantly greater peak rotations per minute than PRE (p=0.001) and PERI (p=0.042) during the first training session. No significant group(&)#215;time interactions existed for absolute V?O2max (p=0.386), relative V?O2max (p=0.341) or maximum workload (p=0.593). However, there was a significant group(&)#215;time interaction (p=0.030) for FTs, with POST having significantly greater changes than PRE (p=0.026) and PERI (p=0.023), and was the only group to experience a significant improvement in FTs from training (p(<)0.001). In addition, magnitude based inferences revealed that POST had Likely improvements in all measures of maximal aerobic performance, while PERI only had Likely improvements in maximum workload and PRE experienced Trivial changes. Furthermore, all measured FTs experienced Likely or Very Likely improvements amongst POST; however, PRE and PERI only had improvements in NFT and HHbBP. Conclusion: SIT improved maximal aerobic performance and FTs in POST, but had limited affects in PRE and PERI. The maturity-related differences in the adaptations to SIT may be due to the differences in performance during the training program or underlying physiological changes that occur with maturation.
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Date Issued: 2017
Identifier: CFE0006934, ucf:51644
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006934

Title: Physiological Muscle Qualitative Changes in Response to Resistance Training in Older Adults.
Creator: Scanlon, Tyler, Fragala, Maren, Hoffman, Jay, Stout, Jeffrey, University of Central Florida
Abstract / Description: Muscle function is determined by structure and morphology at the architectural level. In response to resistance training, older adults have demonstrated that the neuromuscular system has a substantial adaptability, which may compensate for muscle size and quality and lead to improved functional capacities and higher quality of life. PURPOSE: The purpose of this study was to examine the effect of six weeks of progressive resistance exercise on muscle morphology and architecture in healthy...
Show moreMuscle function is determined by structure and morphology at the architectural level. In response to resistance training, older adults have demonstrated that the neuromuscular system has a substantial adaptability, which may compensate for muscle size and quality and lead to improved functional capacities and higher quality of life. PURPOSE: The purpose of this study was to examine the effect of six weeks of progressive resistance exercise on muscle morphology and architecture in healthy older adults. METHODS: Twenty- five healthy men and women were randomly assigned to either six weeks of progressive resistance training (RT) (n=13; age = 71.08 (&)#177; 6.75, BMI = 28.5 (&)#177; 5.22) or to serve as a control (CON) (n = 12; age = 70.17 (&)#177; 5.58, BMI = 27.52 (&)#177; 5.6). Fat mass (FM), lean mass (LM), and lean thigh mass (LTM) were evaluated using dual x-ray absorptiometry. Lower body strength was estimated by predicting maximal knee extensor strength (1RM). Muscle quality (MQ) was evaluated as strength per unit mass (kg/kg). Cross-sectional area (CSA), muscle thickness (MT), fascicle length (Lf), pennation angle (cos?), and echo intensity (EI) of the rectus femoris (RF) and vastus lateralis (VL) were collected using B-mode ultrasound and extended field of view (FOV) ultrasound. EI was quantified using grayscale analysis software. Strength per unit of echo intensity (REI) was determined by dividing 1RM by EI of the thigh. Physiological cross-sectional area (PCSA) was calculated as the ratio of (CSA x cos?) / (EI x Lf). A 2x2 (group [exercise vs. control] x time [pre vs. post]) repeated measures ANOVA was used to identify group differences and group x time interactions and stepwise regression was performed to assess variables related to strength. RESULTS: 1RM increased by 31.9% (p ? 0.01) in the RT group and was significantly correlated to PCSA of the thigh (r = .579; p = .003) at baseline. MQ increased 31.4% (p ? 0.01) in the RT group consistent with an REI increase of 33.3% (p ? 0.01). There were no significant changes in LTM in either group. VL CSA increased 7.4%, (p ? 0.05) and demonstrated a significant interaction (p ? 0.05) in the RT group. There were no significant changes in the CON group for 1RM, MQ, REI or VL CSA. PCSA demonstrated a significant (p ? 0.05) group x time interaction but did not significantly change in either group. EI did not significantly change in the RT or CON groups. CONCLUSION: Calculated PCSA of the thigh assessed by ultrasound was related to the force producing capacity of muscle and demonstrated a significant interaction following resistance training. Short term resistance exercise training was effective in increasing 1RM, muscle quality as relative strength, muscle quality as relative echo intensity, and muscle morphology, but not EI. In addition, ultrasonography appears to be a safe, feasible, informative and sensitive clinical technique to aid in our understanding of muscle strength, function, and quality.
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Date Issued: 2013
Identifier: CFE0004748, ucf:49782
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004748

Title: Determination of Critical Rest Interval using Repeated Sprint Ability Testing.
Creator: Lamonica, Michael, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
Abstract / Description: The critical power (CP) concept has been used to determine the appropriate rest interval during intermittent exercise through the investigation of critical rest interval (CRI). Repeated sprint ability (RSA) testing has been developed to define the athlete's ability to recover and maintain maximal effort during successive bouts. The CP model has been used to understand the physiological responses involved with intermittent exercise delineating between severe and heavy exercise intensity...
Show moreThe critical power (CP) concept has been used to determine the appropriate rest interval during intermittent exercise through the investigation of critical rest interval (CRI). Repeated sprint ability (RSA) testing has been developed to define the athlete's ability to recover and maintain maximal effort during successive bouts. The CP model has been used to understand the physiological responses involved with intermittent exercise delineating between severe and heavy exercise intensity domains. The primary purpose of this study was to determine the CRI from the work-time relationship given by RSA testing using varying work to rest ratios. The secondary purpose was to determine the validity of CRI by evaluation of physiological responses above and below estimated rest interval values during intermittent cycling.Twelve recreationally trained males (mean (&)#177; SD; age 24.1 (&)#177; 3.6yr; height 175.8 (&)#177; 7.0cm; weight 77.6 (&)#177; 12.8kg; V?O2peak 43.3 (&)#177; 5.6ml/kg/min; Body Fat (%) 24.5 (&)#177; 4.4) were recruited for this study. Participants performed a graded exercise test to determine V?O2peak and peak heart rate. Eight participants completed the same three RSA protocols with 6s maximal sprints and varying rest intervals (12-24s) on a cycle ergometer. Intermittent critical power (ICP) was calculated through the linear total work (TW) and time-to-exhaustion (TTE) relationship, whereas CRI was estimated using the average work per sprint and ICP. Seven subjects completed trials above and below estimated CRI to evaluate the validity of this estimate through the examination of the physiological responses. Breath-by-breath oxygen consumption (V?O2) and heart rate (HR) values were recorded during the validation trials. One-way repeated measures analysis of variance (ANOVA) was used to analyze the variables from the RSA trials. Paired samples t-tests were performed to compare performance and physiological variables above or below CRI during the validation trials. Two-way repeated measures ANOVA was used to examined the changes in oxygen consumption (V?O2), HR, mean power (MP), and TW throughout the validation trials. Significant differences (p (<) 0.1) were found for the number of intervals completed, TTE, average work per sprint, peak and mean V?O2 between RSA protocols. Linearity between TW and TTE was r2 = 0.952 (&)#177; 0.081. During the validation trials, TTE was significantly greater in the above versus the below CRI trial (2270.43 (&)#177; 941.15s vs. 1511.00 (&)#177; 811.0s). Furthermore, blood lactate concentration (8.94 (&)#177; 4.89mmol/L vs. 6.56 (&)#177; 3.45mmol/L), AveV?O2 (2.05 (&)#177; 0.36L/min vs. 1.78 (&)#177; 0.26L/min), V?O2peak (2.84 (&)#177; 0.48L/min vs. 2.61 (&)#177; 0.43L/min), and AveHR (151.14 (&)#177; 18.46bpm vs. 138.14 (&)#177; 17.51L/min) were significantly greater in the below CRI trial when compared to the above CRI trial. Significant interactions were found between above and below trials within minimal V?O2 response (F = 6.886, p = 0.024, ?2 = 0.534) to the recovery intervals and maximal HR (F = 4.51, p = 0.016, ?2 = 0.429) response to the work intervals. During the above CRI trial, minimal V?O2 response decreased over time (51-43%V?O2 peak) while maximal HR response achieved a steady state level (81-84%HRpeak). Conversely, minimal V?O2 response during the below CRI trial achieved a steady state level (54-58%V?O2 peak), whereas maximal HR response increased over time (84-90%HRpeak).The relationship between TW and TTE is appropriate for use with RSA testing with varying rest intervals. The differing physiological response during the validation trials may reflect changes in energy system contribution. In conclusion, CRI distinguished between physiological responses related to exercise intensity domains in a manner similar to CP estimates determined from other testing and exercise modalities.
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Date Issued: 2014
Identifier: CFE0005645, ucf:50168
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005645

Title: Phosphatidic Acid Increases Lean Body Tissue and Strength In Resistance Trained Men.
Creator: Williams, David, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, University of Central Florida
Abstract / Description: ABSTRACTPhosphatidic Acid (PA) is a natural phospholipid compound derived from lecithin which is commonly found in egg yolk, grains, fish, soybeans, peanuts and yeast. It has been suggested that PA is involved in several intracellular processes associated with muscle hypertrophy. Specifically, PA has been reported to activate protein synthesis through the mammalian target of rapamycin (mTOR) signaling pathway and thereby may enhance the anabolic effects of resistance training. To our...
Show moreABSTRACTPhosphatidic Acid (PA) is a natural phospholipid compound derived from lecithin which is commonly found in egg yolk, grains, fish, soybeans, peanuts and yeast. It has been suggested that PA is involved in several intracellular processes associated with muscle hypertrophy. Specifically, PA has been reported to activate protein synthesis through the mammalian target of rapamycin (mTOR) signaling pathway and thereby may enhance the anabolic effects of resistance training. To our knowledge, no one has examined the effect of PA supplementation in humans while undergoing a progressive resistance training program. To examine the effect of PA supplementation on lean soft tissue mass (LM) and strength after 8 weeks of resistance training.Fourteen resistance-trained men (mean (&)#177; SD; age 22.7 (&)#177; 3.3 yrs; height: 1.78 (&)#177; 0.10m; weight: 89.3 (&)#177; 16.3 kg) volunteered to participate in this randomized, double-blind, placebo-controlled, repeated measures study. The participants were assigned to a PA group (750mg/day; Mediator(&)#174;, ChemiNutra, MN, n=7) or placebo group (PL; rice flower; n=7), delivered in capsule form that was identical in size, shape and color. Participants were tested for 1RM strength in the bench press (BP) and squat (SQ) exercise. LM was measured using dual-energy X-ray absorptiometry. After base line testing, the participants began supplementing PA or PLfor 8 weeks during a progressive resistance training program intended for muscular hypertrophy. Data was analyzed using magnitude-based inferences on mean changes for BP, SQ and LM. Furthermore, the magnitudes of the inter-relationships between changes in total training volume and LM were interpreted using Pearson correlation coefficients, which had uncertainty (90% confidence limits) of approximately +0.25.In the PA group, the relationship between changes in training volume and LM was large(r=0.69, +0.27; 90%CL), however, in the PL group the relationship was small (r=0.21, +0.44; 90%CL). PA supplementation was determined to be likely beneficial at improving SQ and LM over PL by 26% and 64%, respectively. The strong relationship between changes in total training volume and LM in the PA group suggest that greater training volume most likely lead to the greater changes in LM, however, no such relationship was found with PL group. For the BP data, the PA group resulted in a 42% greater increase in strength over PL, although the effect was considered unclear. While more research is needed to elucidate mechanism of action; the current findings suggest that in experienced resistance trained men supplementing 750mg PA per day for 8 weeks may likely benefit greater changes in muscle mass and strength compared with resistance training only. ?
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Date Issued: 2012
Identifier: CFE0004641, ucf:49897
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004641

Title: The Effects of 6-weeks of Resistance Training on the Neuromuscular Fatigue Threshold in Older Adults.
Creator: Emerson, Nadia, Stout, Jeffrey, Hoffman, Jay, Fragala, Maren, University of Central Florida
Abstract / Description: Age-related deficits in muscle mass, strength, and function place an increased burden of work on existing skeletal muscle and may lead to early onset of neuromuscular fatigue (NMF) during activities of daily living. Resistance exercise (RE) is the proven method for improving neuromuscular function in healthy older adults. PURPOSE: To investigate the effects of 6 weeks of RE on the NMF threshold as well as strength and functional performance in older adults. METHODS: Twenty-four older adults...
Show moreAge-related deficits in muscle mass, strength, and function place an increased burden of work on existing skeletal muscle and may lead to early onset of neuromuscular fatigue (NMF) during activities of daily living. Resistance exercise (RE) is the proven method for improving neuromuscular function in healthy older adults. PURPOSE: To investigate the effects of 6 weeks of RE on the NMF threshold as well as strength and functional performance in older adults. METHODS: Twenty-four older adults were randomly assigned to 6 weeks of RE (EXE; n = 12; age 72 (&)#177; 6.3 y; BMI 28.4 kg/m2) or control (CONT; n = 12; age 70.3 (&)#177; 5.6 y; BMI 27.6 kg/m2). Body fat percent (BF%), lean mass (LM), and fat mass (FM) were measured using DEXA and participants performed a discontinuous cycle ergometer test, physical working capacity at fatigue threshold (PWCFT), to determine the onset of NMF. Functional performance was assessed by time to complete 5 chair rises (CHAIR) and walk an 8-foot course (WALK). Lower body strength was assessed by predicted 1-RM leg extension (1RM). Two-way Analysis of Variance (ANOVA; time [PRE, POST] x group [EXE and CONT]) and magnitude based inferences were used to compare dependent variables. RESULTS: RE significantly increased 1RM (35%; p = 0.001) and CHAIR (20%; p = 0.047). RE had a likely beneficial effect on WALK (15%) and a possibly beneficial effect on PWCFT (14%). There were no significant changes to LM or FM, however, women in EXE significantly decreased BF% (p = 0.020). CONCLUSION: Results suggest that RE improves measures of strength and functional performance and possibly the onset of NMF in older adults.
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Date Issued: 2013
Identifier: CFE0004679, ucf:49876
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004679

Title: Effect of Acute L-Alanyl-L-Glutamine (Sustamine) and Electrolyte Ingestion on Cognitive Function, Multiple Object Tracking and Reaction Time Following Prolonged Exercise.
Creator: Pruna, Gabriel, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
Abstract / Description: Changes in physiological function occurring during a body water deficit may result in significant decrements in performance, cognitive function and fine motor control during exercise. This may be due to the magnitude of the body water deficit. Rehydration strategies are important to prevent these deleterious effects in performance. The purpose of this study was to examine the changes before and after prolonged exercise of an alanine-glutamine dipeptide (AG) on cognitive function and reaction...
Show moreChanges in physiological function occurring during a body water deficit may result in significant decrements in performance, cognitive function and fine motor control during exercise. This may be due to the magnitude of the body water deficit. Rehydration strategies are important to prevent these deleterious effects in performance. The purpose of this study was to examine the changes before and after prolonged exercise of an alanine-glutamine dipeptide (AG) on cognitive function and reaction time.Twelve male endurance-trained runners (age: 23.5 (&)#177; 3.7 y; height: 175.5 (&)#177; 5.4 cm; weight: 70.7 (&)#177; 7.6 kg) participated in this study. Participants were asked to run on a treadmill at 70% of their predetermined VO2max for 1 h and then run at 90% of VO2max until volitional exhaustion on four separate days (T1-T4). T1 was a dehydration trial and T2-T4 were all different hydration modalities (electrolyte drink, electrolyte drink with a low dose of AG, electrolyte drink with a high dose of AG, respectively) where the participants drank 250 mL every 15 min. Before and after each hour run, cognitive function and reaction tests were administered. Hopkins Magnitude Based Inferences were used to analyze cognitive function and reaction time data.Results showed that physical reaction time was likely faster for the low dose trial than the high dose trial. Dehydration had a possible negative effect on the number of hits in 60-sec compared to both the low and high dose trials. Comparisons between only the electrolyte drink and the high dose ingestion appeared to be possibly negative. Analysis of lower body quickness indicates that performance in both the low and high dose trials were likely improved (decreased) in comparison to the dehydration trial. Multiple object tracking analysis indicated a possible greater performance for dehydration and low dose compared to only the electrolyte drink, while there was a likely greater performance in multiple object tracking for the high dose trial compared to consumption of the electrolyte drink only. The serial subtraction test was possibly greater in the electrolyte drink trial compared to dehydration.Rehydration with the alanine-glutamine dipeptide during an hour run at a submaximal intensity appears to maintain or enhance subsequent visual reaction time in both upper and lower body activities compared to a no hydration trial. The combination of the alanine-glutamine dipeptide may have enhanced fluid and electrolyte absorption from the gut and possibly into skeletal tissue to maintain neuromuscular performance.
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Date Issued: 2014
Identifier: CFE0005233, ucf:50583
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005233

Title: Endocrine and Contralateral Muscle Responses to Short-term Unilateral Resistance Training.
Creator: Boone, Carleigh, Fragala, Maren, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description: PURPOSE: The purpose of this study was to examine the effects of short-term lower body unilateral resistance training on hormonal, muscle morphological, and performance measures in young men. METHODS: Seventeen healthy, untrained young men (Age: 22.8 (&)#177; 3.7 y; BMI: 26.5 (&)#177; 4.9 kg/m2) were randomly assigned to one of two groups (UT: 22.9 (&)#177; 4.6 y, 25.3 (&)#177; 4.2 kg/m2; CON: 24.0 (&)#177; 4.6 y, 27.7 (&)#177; 5.1 kg/m2). Resistance training consisted of 4 weeks of...
Show morePURPOSE: The purpose of this study was to examine the effects of short-term lower body unilateral resistance training on hormonal, muscle morphological, and performance measures in young men. METHODS: Seventeen healthy, untrained young men (Age: 22.8 (&)#177; 3.7 y; BMI: 26.5 (&)#177; 4.9 kg/m2) were randomly assigned to one of two groups (UT: 22.9 (&)#177; 4.6 y, 25.3 (&)#177; 4.2 kg/m2; CON: 24.0 (&)#177; 4.6 y, 27.7 (&)#177; 5.1 kg/m2). Resistance training consisted of 4 weeks of unilateral lower body and bilateral upper body exercises on 3 days per week. Each training session entailed unilateral countermovement jumps (3 (&)#215; 8), unilateral leg press (LP), bilateral chest press (CP), unilateral leg extension (LE), and bilateral low row (LR). Strength exercises were performed for 3 sets of 8-10 repetitions; lower body exercises were performed with the dominant leg only. Muscle thickness (MT), pennation angle (PA), cross-sectional area (CSA), and echo-intensity (EI) of the vastus lateralis (VL) and rectus femoris (RF) muscles of both legs was assessed via ultrasound. Fascicle length (FL) was calculated as [MT / sin(PA)]. Maximal dynamic unilateral LP and LE strength was assessed during one-repetition maximum (1RM) testing; CP and LR 1RM strength was estimated as [repetition weight/(1.0278-0.0278)(reps)]. Maximal isometric knee extensor strength was isolaterally assessed via maximal voluntary contraction (MVC) testing. Mean and peak power output (Watts) was quantified during unilateral countermovement jumps via accelerometry. Fasting concentrations of total testosterone and growth hormone were obtained at baseline (PRE), immediately post (IP), 30-minutes post (30P), and 60-minutes post (60P) during both testing exercise sessions (Pre and Post). Following the 4-week intervention, all participants' maximal dynamic and isometric strength, mean and peak power output, muscle morphology, and hormonal responses were reassessed. Performance, ultrasound, and area under the curve data were analyzed using ANCOVA to observe between-group comparisons while controlling for baseline (PRE) values. Endocrine data were analyzed using a two-way, mixed-factorial repeated-measures ANOVA. RESULTS: Participants in the UT group experienced significant strength improvements of the trained (28 to 150%) and untrained legs (12 to 160%). Training did not elicit significant improvements in maximal isometric strength or power output of the trained or untrained leg. The trained RF experienced significant increases in CSA and MT. The trained VL experienced a significant increase in CSA. Muscle size of the untrained leg was not significantly augmented. Training did not elicit changes in the acute hormonal response to exercise. CONCLUSIONS: Four weeks of unilateral lower body resistance training using the dominant leg appears sufficient to evoke strength gains of both the ipsilateral and contralateral legs. However, meaningful morphological changes were observed in the trained leg only. Differences in acute hormonal responses to resistance exercise did not appear to explain the observed differences. In addition, unilateral lower body resistance training did not appear to augment the acute endocrine response to an acute bout of resistance exercise. Current findings suggest that the cross-educational strength transfer during the early stage of training is attributable to factors other than changes in muscle morphology and circulating hormones.
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Date Issued: 2014
Identifier: CFE0005307, ucf:50538
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005307

Title: The Cross Education of Neuromuscular Economy.
Creator: Beyer, Kyle, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, University of Central Florida
Abstract / Description: Cross education is the phenomenon by which the untrained limb will experience a gain in strength following a unilateral resistance training program. However, little is known as to the underlying adaptation occurring in the untrained limb. Purpose: To examine the effect of dynamic unilateral resistance training on the strength and neuromuscular adaptations of both the trained and untrained legs. Methods: Eight previously untrained males (22.38(&)#177;2.92 y, 1.73(&)#177;0.08 m, 75.26(&)#177;14...
Show moreCross education is the phenomenon by which the untrained limb will experience a gain in strength following a unilateral resistance training program. However, little is known as to the underlying adaptation occurring in the untrained limb. Purpose: To examine the effect of dynamic unilateral resistance training on the strength and neuromuscular adaptations of both the trained and untrained legs. Methods: Eight previously untrained males (22.38(&)#177;2.92 y, 1.73(&)#177;0.08 m, 75.26(&)#177;14.53 kg) completed a four-week unilateral resistance training program, while another eight untrained males (24.00(&)#177;4.57 y, 1.84(&)#177;0.05 m, 94.21(&)#177;16.14 kg) served as controls. Isometric leg extension strength, leg press 1 repetition maximum (1RM), leg extension 1RM, root mean square of the maximal electromyographic amplitude (EMG), submaximal EMG, dynamic neuromuscular economy (NME) and the slope of NME-power output relationship were determined before and after training to assess the changes in strength and neuromuscular adaptations of the vastus lateralis (VL) and rectus femoris (RF) in both the trained and untrained legs. The unilateral resistance training program was conducted on the dominant leg (DOM) in the unilateral resistance training group (URT) and was compared to the dominant leg of the control group (CON). Cross education was measured in the nondominant leg (NON) for both groups. The unilateral resistance training program was completed three days per week for a total of twelve training sessions. Exercises included in the training program were unilateral leg press, unilateral leg extension, bilateral chest press and bilateral low row. All data was analyzed using one-way analysis of covariance of the post-testing values using the pre-testing values as the covariate. Further analysis of the EMG and NME data was performed using magnitude-based inferences. Results: The URT group improved their isometric (DOM:11.03%, NON:4.98%), leg press (DOM:77.63%, NON:64.88%) and leg extension (DOM:46.76%, NON:16.43%) strength after the four weeks of resistance training. There was no difference between the groups in isometric strength in the dominant (p=0.188) or nondominant (p=0.948) leg. For leg extension 1RM, there was a significant difference between groups in the dominant leg (p=0.018), but not the nondominant leg (p=0.482). However, there were significant group differences in both the dominant (p=0.003) and nondominant (p=0.034) leg for leg press 1RM. In terms of maximal EMG, the training groups improved in the vastus lateralis (DOM:29.81%, NON:31.44%) and rectus femoris (DOM:20.71%, NON:6.26%) individually, as well as in total EMG (DOM:24.78%, NON:17.57%). There was a Likely Positive or Very Likely Positive effect of unilateral resistance training on the changes in maximal EMG of the vastus lateralis and rectus femoris in both the dominant and nondominant legs. There was a Likely Positive effect of unilateral resistance training on the submaximal EMG of the dominant vastus lateralis at 75 and 125 watts. Conversely, in the rectus femoris, there was Unclear effects of unilateral resistance training on the submaximal EMG of the dominant leg. There was no consistent effect of unilateral resistance training on submaximal EMG values of the vastus lateralis in the nondominant leg. However, the rectus femoris in the nondominant leg experienced a Likely Positive effect of unilateral resistance training on submaximal EMG. NME improved in the URT group in the VL at 75 (DOM:9.73%, NON:13.42%), 100 (DOM:8.76%, NON:8.21%), and 125(DOM:24.26%, NON:12.8%) watts and in the RF at 75 (DOM:22.25%, NON:15.73%), 100(DOM:24.85%, NON:17.05%) and 125 (DOM:30.99%) watts. In terms of neuromuscular economy, there was a Likely Positive or Very Likely Positive effect of unilateral resistance training on most measures of NME on both the vastus lateralis and rectus femoris in both the dominant and nondominant legs. In terms of NME slope, there was only a Likely Positive effect of unilateral resistance training on the dominant vastus lateralis. Conclusion: Based on these results, it appears that the cross education of strength from unilateral resistance training is modality-specific. Furthermore, the NME of both the vastus lateralis and rectus femoris in both legs appear to improve following unilateral resistance training. However, in the nondominant leg, the improvement in NME appears to be due solely to the increase in maximal EMG, whereas the improved NME in the dominant leg is due to both an increase in maximal EMG and a decrease in submaximal EMG.
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Date Issued: 2014
Identifier: CFE0005305, ucf:50537
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005305

Title: Getting The Work Out of Workouts: Evaluating the Effectiveness and Outcomes of a Physical Exercise Motivational Intervention For Older Workers.
Creator: Sholar-Fetherlin, Brandon, Fritzsche, Barbara, Smither, Janan, Wang, Wei, Fragala, Maren, University of Central Florida
Abstract / Description: To mitigate their estimated $300 billion in annual health-related losses, many companies have instituted workplace wellness initiatives designed to promote physical activity among their employees, improving the overall health of their workforce. Though middle-aged and older workers may potentially enjoy the greatest physical, stress and cognitive benefits from regular exercise, workplace wellness programs have been less successful in attracting such employees. This study developed and tested...
Show moreTo mitigate their estimated $300 billion in annual health-related losses, many companies have instituted workplace wellness initiatives designed to promote physical activity among their employees, improving the overall health of their workforce. Though middle-aged and older workers may potentially enjoy the greatest physical, stress and cognitive benefits from regular exercise, workplace wellness programs have been less successful in attracting such employees. This study developed and tested a 6-week exercise motivation intervention designed to meet the needs of sedentary, older working adults and to determine what non-physical benefits might result from increased levels of physical exercise. The intervention, based primarily on Self-Determination Theory, included feedback on individually-made, realistic, process-specific exercise goals that and provided guidance from knowledgeable exercise professionals in addition to support group of socially-similar individuals to aid in coping and adherence. The intervention was built and delivered entirely online to fit better with the sample's considerable time demands. The motivational intervention was delivered to a sample of 30 mostly-older working adults and was successful in significantly improving activity levels and overall affect while decreasing stress. No significant differences were detected in measures of personal resources, work engagement, work effort and task performance. The implications and recommendations for future research are discussed.
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Date Issued: 2017
Identifier: CFE0006660, ucf:51235
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006660

Title: The effect of moderate altitude on high intensity running performance during a game with collegiate female soccer players.
Creator: Bohner, Jonathan, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description: Competition often requires teams that reside at sea level to compete against opponents whose residence is at a moderate altitude. This may pose a potential competitive disadvantage considering that moderate altitude may cause decrements in VO2max, distance covered, and time to exhaustion in endurance athletes. The purpose of this study was to examine the effect of altitude on game performance measures. Six NCAA Division I female soccer players (20.33 (&)#177; 1.21 y; 168 (&)#177; 6.45 cm; 62...
Show moreCompetition often requires teams that reside at sea level to compete against opponents whose residence is at a moderate altitude. This may pose a potential competitive disadvantage considering that moderate altitude may cause decrements in VO2max, distance covered, and time to exhaustion in endurance athletes. The purpose of this study was to examine the effect of altitude on game performance measures. Six NCAA Division I female soccer players (20.33 (&)#177; 1.21 y; 168 (&)#177; 6.45 cm; 62.5 (&)#177; 6.03 kg) were retrospectively examined. Comparisons were made between two competitions that were played at sea level (SL) within two weeks of a game played at a moderate altitude (1840 m) on game characteristics including high intensity running (HIR) and total distance covered (TDC). Analysis was performed on these six players who met a threshold of playing sixty or more minutes in each competition. A 10-Hz global positioning system (GPS) was used to measure distance and velocity. The rate of TDC and HIR during the game (m?min-1) and percentage of time at HIR during competition were evaluated. The two games at SL were averaged to establish baseline performance and the mean results were compared with the single game played at altitude. Paired samples t-tests were performed to determine if any mean differences existed between performance at altitude and sea level.Significant differences (p (<) 0.05) were seen in minutes played between the games at SL (74.23 (&)#177; 2.93 min) versus altitude (83.24 (&)#177; 5.27 min). The relative distance rate during the game at altitude was lower at altitude (105.77 (&)#177; 10.19 m?min-1) than at SL (120.55 (&)#177; 8.26 m?min-1). HIR rate was greater at SL (27.65 (&)#177; 9.25 m?min-1) compared to altitude (25.07 (&)#177; 7.66 m?min-1). The percent of time spent at high intensity was not significantly different (p = 0.064), yet tended to be greater at sea level (10.4 (&)#177; 3.3%) than when they performed at altitude (9.1 (&)#177;2.2%).Soccer performance at a moderate altitude appears to reduce the rate at which players run throughout the competition, as well as their rate at a high intensity. Results suggest that teams that reside at SL may be at a competitive disadvantage when competing at altitude.
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Date Issued: 2014
Identifier: CFE0005134, ucf:50716
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005134

Title: Do Changes in Muscle Architecture Effect Post- Activation Potentiation.
Creator: Reardon, Danielle, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description: Purpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 (&)#177; 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2(&)#177;3.6y; 90.67(&)#177;12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout...
Show morePurpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 (&)#177; 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2(&)#177;3.6y; 90.67(&)#177;12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout (CON), with each protocol being separated by one week. During each testing session ultrasound and vertical jump testing were assessed at baseline (BL), 8min post (8P) and 20min post (20P) workout. Ultrasound measures of the rectus femoris (RF) and vastus lateralis (VL) muscles included; cross sectional area (CSA) and pennation angle (PNG). Following each ultrasound, peak (PVJP) and mean (MVJP) vertical jump power (using hands for maximum jump height) were measured using an accelerometer. Results: Magnitude based inferences analysis indicated that in comparison to CON, 75% resulted in a likely greater change in RF-CSA and VL-CSA (BL-8P and BL(-)20P), 90% resulted in a likely greater RF-CSA and VL-CSA (BL(-)20P), and 100% resulted in a very likely or likely decrease in VL-PNG at BL-8P and BL(-)20P, respectively). Meanwhile, changes in PVJP and MVJP for the 75% trial was likely decreased at BL-8P and BL(-)20P; and for the 90% trial MVJP was likely decreased at BL-8P and BL(-)20P. Analysis of the magnitude of the relationships indicated a likely negative relationship between VL-PNG and MVJP (r = -0.35; p (<) 0.018) at BL-8P, while at BL(-)20P, a negative relationship was observed between PVJP and RF-CSA (r = -0.37; p (<) 0.014). Conclusion: Acute increases in muscle size and acute decreases in pennation angle did not result in any potentiation in vertical jump power measures. Although the inverse relationships observed between muscle architecture variables and power suggests a potential effect, the change in position (i.e. movement from standing to supine for ultrasound measures) may negate, as a result of potential fluid shifts or muscle relaxation, the potentiating effects of the exercise. It is also possible that the fatiguing nature of the squat protocols in trained but not competitive participants may have also contributed to the results.
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Date Issued: 2013
Identifier: CFE0005048, ucf:49963
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005048

Title: The Effects of High-Intensity Interval Training and 28 days of [Beta]-Hydroxy-[Beta]-Methybutyrate Supplementation on Measures of Aerobic Power and Metabolic Thresholds.
Creator: Robinson, Edward, Stout, Jeffrey, Hoffman, Jay, Fragala, Maren, Fukuda, David, Ferguson, Matthew, University of Central Florida
Abstract / Description: Purpose: To examine the effects of 28 days of ?-hydroxy-?-methylbutyrate free acid (HMB) and high-intensity interval training (HIIT) on maximal oxygen consumption (VO2peak), ventilatory threshold (VT), respiratory compensation point (RCP) and time to exhaustion (Tmax) in college-aged men and women. Methods: Healthy men and women (n=34, age and V ?O2peak= 22.7+3.1yr and 39.3+5.0 mL.kg-1.min-1, respectively) participated in this study. All participants completed a series of tests prior and...
Show morePurpose: To examine the effects of 28 days of ?-hydroxy-?-methylbutyrate free acid (HMB) and high-intensity interval training (HIIT) on maximal oxygen consumption (VO2peak), ventilatory threshold (VT), respiratory compensation point (RCP) and time to exhaustion (Tmax) in college-aged men and women. Methods: Healthy men and women (n=34, age and V ?O2peak= 22.7+3.1yr and 39.3+5.0 mL.kg-1.min-1, respectively) participated in this study. All participants completed a series of tests prior and subsequent to treatment. A maximal oxygen consumption test was performed on a cycle ergometer to assess VO2peak, Tmax, VT, and RCP. The peak power output (Ppeak), power at VT (PVT) and power at RCP (PRCP) were also recorded from this test. Twenty-six subjects completed 12 HIIT (80-120% maximal workload) exercise sessions consisting of 5-6 bouts of a 2:1 minute cycling work to rest ratio protocol over a four-week period, while eight served as controls (CTL). In double-blind fashion, the HIIT groups were assigned into either a placebo (HIIT) or 3g per day of HMB (HMB-HIIT). Body composition was measured with dual energy x-ray absorptiometry (DEXA). Outcomes were assessed by ANCOVA with posttest means adjusted for pretest differences. Results: The HMB-HIIT intervention showed significant (p(<)0.05) gains in VO2peak, VT, and PVT versus the CTL and HIIT group. Both HIIT and HMB-HIIT treatment groups demonstrated significant (p(<)0.05) improvement over CTL for Ppeak, Tmax, RCP, and PRCP with no significant difference between the treatment groups. There were no significant differences observed for any measures of body composition. An independent-samples t-test confirmed that there were no significant differences between the training volumes for the HIIT and HMB-HIIT groups. Conclusion: These findings suggest that the addition of HMB supplementation may result in greater changes in VO2peak and VT than HIIT alone. Therefore, in college-aged men and women, the use of HMB supplementation may enhance the benefits of HIIT on aerobic performance measures.
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Date Issued: 2014
Identifier: CFE0005240, ucf:50604
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005240

Title: Watch Me Disappear: Gendered Bodies, Pro-Anorexia, and Self-Injury in Virtual Communities.
Creator: Preston-Sidler, Leandra, Bowdon, Melody, Scott, Blake, Marinara, Martha, Fragala, Maren, University of Central Florida
Abstract / Description: This project examines the relationship between gendered identities, virtual communities, and material bodies, with an emphasis on eating disorders and self-injury practices. The use of the internet to represent and foster particular categories of material bodies, such as the anorexic, the fitness buff, and the self-injurer, has gained substantial visibility due in part to the proliferation of visual imagery presented through social networks. I analyze written and visual texts within specific...
Show moreThis project examines the relationship between gendered identities, virtual communities, and material bodies, with an emphasis on eating disorders and self-injury practices. The use of the internet to represent and foster particular categories of material bodies, such as the anorexic, the fitness buff, and the self-injurer, has gained substantial visibility due in part to the proliferation of visual imagery presented through social networks. I analyze written and visual texts within specific social networks to assess their function and potential impact on individuals and larger communities.Drawing from Donna Haraway's cyborg theory, N. Kathryn Hayles' posthuman, Judith Butler's performativity, feminist poststructural analysis, and the notion of augmented reality, this project explores how individuals rely on social networks, images, and technologies to provide supportive environments for, as well as modify and maintain, specific gendered bodies. Applying feminist interpretations of Foucault's concepts of discipline and (")docile bodies,(") primarily the research and critiques of Susan Bordo, Anne Balsamo, and Armando Favazza (among others), I examine how image sharing and interactions via social networks and communities affect material bodies and function as forms of social control, normalizing and encouraging ultra-thin bodies and dangerous behaviors, including eating disorders, overexercise, and cutting. I also explore subversive strategies of resistance enacted both within and beyond pro-ana and self-injury communities to counter negative messages and promote positive body image in girls and women.
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Date Issued: 2015
Identifier: CFE0005690, ucf:50125
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005690

Title: Effect of Acute L-Alanyl-L-Glutamine (Sustamine) and Electrolyte Ingestion on Plasma Electrolytes, Physiologic Measures, and Neuromuscular Fatigue during Endurance Exercise.
Creator: McCormack, William, Hoffman, Jay, Stout, Jeffrey, Fragala, Maren, Virgets, Thomas, University of Central Florida
Abstract / Description: The purpose of this study was to compare the efficacy of two dose levels of L-Alanyl-L-Glutamine in a commercially available sports drink to the sports drink only on time to exhaustion,neuromuscular fatigue and physiological measures during prolonged endurance exercise. Twelve endurance-trained males (23.5(&)#177;3.7 yrs; 175.5(&)#177;5.4 cm; 70.7(&)#177;7.6 kg) performed four trials, each consisting of 1 hr treadmill runs at 75% of VO2peak followed by a run to exhaustion at 90% of VO2peak....
Show moreThe purpose of this study was to compare the efficacy of two dose levels of L-Alanyl-L-Glutamine in a commercially available sports drink to the sports drink only on time to exhaustion,neuromuscular fatigue and physiological measures during prolonged endurance exercise. Twelve endurance-trained males (23.5(&)#177;3.7 yrs; 175.5(&)#177;5.4 cm; 70.7(&)#177;7.6 kg) performed four trials, each consisting of 1 hr treadmill runs at 75% of VO2peak followed by a run to exhaustion at 90% of VO2peak. The trials differed in type of hydration. One trial consisted of no hydration (NHY),another required ingestion of only a sports drink (ET), and two trials required ingestion of a low dose (LD) (300 mg?500 ml-1) and high dose (HD) of L-Alanyl-L-Glutamine (1 g?500 ml-1) mixedin the sports drink. During the fluid ingestion trials 250 ml were consumed every 15 min. Plasmaglutamine, glucose, electrolytes, and osmolality were measured prior to the run (PRE), and at 30, 45, and 60 min. VO2, RQ, and HR were measured every 15 min and surface electromyography (EMG) of the vastus lateralis and rectus femoris were measured every 10 min during the 1 hr run. Time to exhaustion was significantly longer during the LD and HD trials compared with NHY. Plasma glutamine concentrations were significantly elevated at 45 min in LD and HD trials, and remained elevated at 60 min during HD. Sodium concentrations increased with the beginning of exercise and remained stable for the duration of the 1 hr run. At 60 min plasma sodium was significantly lower in all trials compared with NHY. The results from this study indicated that ingestion of the alanine-glutamine dipeptide at either the low or high dose significantly improved time to exhaustion during high intensity exercise compared to a no hydration trial. These differences were not noted between ET and NHY.
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Date Issued: 2014
Identifier: CFE0005209, ucf:50649
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005209

Electromyography (3)	+ -
Physical Activity (2)	+ -
?-Hydroxy-?-Methylbutyrate (1)	+ -
Aerobic (1)	+ -
Aging (1)	+ -

Alanine-Glutamine (1)	+ -
Altitude (1)	+ -
Caffeine (1)	+ -
Cognition (1)	+ -
Cognitive Function (1)	+ -
Critical Power (1)	+ -
Critical Rest Interval (1)	+ -
Cross Education (1)	+ -
Cross-education (1)	+ -
Cycling (1)	+ -
Differentiation (1)	+ -
Dynavision (1)	+ -
Echo intensity (1)	+ -
Echo-intensity (1)	+ -
Electrolytes (1)	+ -
Endocrine (1)	+ -
Endurance (1)	+ -
Energy expenditure (1)	+ -
Exercise Physiology (1)	+ -
Gas Exchange (1)	+ -
Healthy Aging in the Workplace (1)	+ -
High Intensity Interval Training (1)	+ -
High Intensity Running (1)	+ -
High-Intensity Interval Training (1)	+ -
High-intensity training (1)	+ -

Fragala, Maren (17)	+ -
University of Central Florida (17)	+ -
Hoffman, Jay (15)	+ -
Stout, Jeffrey (15)	+ -
Fukuda, David (9)	+ -

Beyer, Kyle (2)	+ -
Boone, Carleigh (2)	+ -
Lamonica, Michael (2)	+ -
Bohner, Jonathan (1)	+ -
Bowdon, Melody (1)	+ -
Emerson, Nadia (1)	+ -
Ferguson, Matthew (1)	+ -
Fritzsche, Barbara (1)	+ -
Marinara, Martha (1)	+ -
McCormack, William (1)	+ -
Preston-Sidler, Leandra (1)	+ -
Pruna, Gabriel (1)	+ -
Reardon, Danielle (1)	+ -
Robinson, Edward (1)	+ -
Scanlon, Tyler (1)	+ -
Scott, Blake (1)	+ -
Sholar-Fetherlin, Brandon (1)	+ -
Smither, Janan (1)	+ -
Virgets, Thomas (1)	+ -
Wang, Wei (1)	+ -
Wells, Adam (1)	+ -
Williams, David (1)	+ -

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