11 research outputs found

    beta-alanine supplementation improves tactical performance but not cognitive function in combat soldiers

    Get PDF
    Background: There are no known studies that have examined beta-alanine supplementation in military personnel. Considering the physiological and potential neurological effects that have been reported during sustained military operations, it appears that beta-alanine supplementation may have a potential benefit in maintaining physical and cognitive performance during high-intensity military activity under stressful conditions. The purpose of this study was to examine the effect of 28 days of beta-alanine ingestion in military personnel while fatigued on physical and cognitive performance. Methods: Twenty soldiers (20.1 +/- 0.9 years) from an elite combat unit were randomly assigned to either a beta-alanine ( BA) or placebo (PL) group. Soldiers were involved in advanced military training, including combat skill development, navigational training, self-defense/hand-to-hand combat and conditioning. All participants performed a 4-km run, 5-countermovement jumps using a linear position transducer, 120-m sprint, a 10-shot shooting protocol with assault rifle, including overcoming a misfire, and a 2-min serial subtraction test to assess cognitive function before (Pre) and after ( Post) 28 days of supplementation. Results: The training routine resulted in significant increases in 4-km run time for both groups, but no between group differences were seen (p = 0.597). Peak jump power at Post was greater for BA than PL (p = 0.034), while mean jump power for BA at Post was 10.2% greater (p = 0.139) than PL. BA had a significantly greater (p = 0.012) number of shots on target at Post (8.2 +/- 1.0) than PL (6.5 +/- 2.1), and their target engagement speed at Post was also significantly faster (p = 0.039). No difference in serial subtraction performance was seen between the groups (p = 0.844). Conclusion: Results of this study indicate that 4-weeks of beta-alanine ingestion in young, healthy soldiers did not impact cognitive performance, but did enhance power performance, marksmanship and target engagement speed from pre-ingestion levels

    Exercise Maintains Dendritic Complexity In An Animal Model Of Posttraumatic Stress Disorder

    No full text
    Introduction This study examined the effect of endurance exercise on dendritic arborization in the dentate gyrus subregion in rodents exposed to a predator scent stress (PSS). Methods Sprague-Dawley rats were randomly assigned to one of four treatment groups. In two of the groups, rats were unexposed to PSS but either remained sedentary (SED + UNEXP) or were exercised (EX + UNEXP). In the other two groups, rats were exposed to the PSS but either remained sedentary (SED + PSS) or were exercised (EX + PSS). After 6 wk of either exercise or sedentary lifestyle, rats were exposed to either the PSS or a sham protocol. During exercise, the animals ran on a treadmill at 15 m路min-1, 5 min路d-1 gradually increasing to 20 min路d-1, 5 d路wk-1 for 6 wk. Eight days after exposure to either PSS or sham protocol, changes in the cytoarchitecture (dendritic number, dendritic length, and dendrite spine density) of the dentate gyrus subregion of the hippocampus were assessed. Results No differences (P = 0.493) were noted in dendritic number between the groups. However, dendritic length and dendrite spine density for SED + PSS was significantly smaller (P \u3c 0.001) than that observed in all other groups. In addition, neurons from animals in SED + PSS had significantly fewer (P \u3c 0.001) dendritic intersections than all other groups. Conclusion The results of this study indicate that 6 wk of endurance training can protect dendritic length and complexity, suggesting a degree of resiliency to stress. This provides further evidence for supporting the inclusion of an exercise regimen for reducing the risk of posttraumatic stress disorder

    Exercise Enhances The Behavioral Responses To Acute Stress In An Animal Model Of Ptsd

    No full text
    Introduction This study examined the effects of endurance exercise on the behavioral response to stress and patterns of brain-derived neurotrophic factor (BDNF), neuropeptide Y (NPY), and 未-opioid receptor (phospho-DOR) expression in the hippocampus. Methods Animals ran on a treadmill at 15 m路min-1, 5 min路d-1 gradually increasing to 20 min路d-1, 5 d路wk-1 for 6 wk. After training, one group of animals was exposed to a predator scent stress (PSS) protocol for 10 min. Outcome measurements included behavior in an elevated plus-maze (EPM) and acoustic startle response (ASR) 7 d after exposure to stress. Immunohistochemical technique was used to detect the expression of the BDNF, NPY, and phospho-DOR in the hippocampus 8 d after exposure. Results Sedentary animals exposed to PSS were observed to have a greater incidence of extreme behavior responses including higher anxiety, less total activity in the EPM, and greater amplitude in the ASR than unexposed and/or trained animals. Exercise-trained animals exposed to PSS developed a resiliency to the stress, reflected by significantly greater total activity in the EPM, reduced anxiety, and reduced ASR compared to the sedentary, exposed animals. Exercise in the absence of stress significantly elevated the expression of BDNF and phospho-DOR, whereas exposure to PSS resulted in a significant decline in the expression of NPY, BDNF, and phospho-DOR. Trained animals that were exposed maintained expression of BDNF, NPY, and phospho-DOR in most subregions of the hippocampus. Conclusion Results indicated that endurance training provided a mechanism to promote resilience and/or recovery from stress. In addition, exercise increased expression of BDNF, NPY, and DOR signaling in the hippocampus that was associated with the greater resiliency seen in the trained animals

    Examination of Amorphous Calcium Carbonate on the Inflammatory and Muscle Damage Response in Experienced Resistance Trained Individuals

    No full text
    The effect of 3 weeks of amorphous calcium carbonate (ACC) supplementation (2000 mg per day) was examined on the recovery response to resistance exercise. Thirty men were randomized into a supplement (ACC) or placebo (PL) group. Following supplementation, participants performed six sets of 10 repetitions in the bench press (BP) and incline BP exercises, using 80% of maximal strength. Participants returned 24 (T4) and 48 h (T5) later and performed six sets of the BP exercise. Significant decreases in the number of repetitions (p p p = 0.009) were noted over time, but no significant interactions were observed (p > 0.05). Magnitude-based inference analysis (MBI) indicated that the change in repetitions was possibly beneficial for ACC at T4 and likely beneficial at T5. No significant interaction was noted for general soreness (p = 0.452), but a trend toward an interaction was observed in upper body soreness (p = 0.089). Confidence intervals for mean percent change scores indicated significant differences between the groups at T4 and T5, and MBI analysis indicated that ACC was very likely or likely to be beneficial for reducing soreness at those time points. In conclusion, ACC supplementation may have a potential beneficial effect in attenuating the decline in performance, which is possibly due to the carbonate component

    Effect Of High-Dose, Short-Duration 螔-Alanine Supplementation On Circulating Il-10 Concentrations During Intense Military Training

    No full text
    This study examined the effect of 尾-alanine as a potential anti-inflammatory agent during intense military training. Twenty soldiers (20.1 卤 0.6 years) from an elite combat unit were randomly assigned to either a 尾-Alanine (BA) or placebo (PL) group. Soldiers were provided with 12 g路d -1 of either BA or PL for 7 days between 2 intensive periods of navigational training and restricted sleep. During the initial training period, soldiers navigated on average 27.8 km路d -1 with ;50% of their body mass in their packs for 5 days. Soldiers returned to base and began a 7-day supplementation program before departing for an additional period of intense field training. During the second period of field training, soldiers navigated 10 km路d -1 for an additional 5 days, carrying similar loading as the initial week, performed tactical missions, and slept approximately 5 hours per day. Blood samples were obtained after the initial training period and after the second training period and analyzed for IL-10. Magnitude-based inferences that were used to provide inferences on the true effect BA may have had on IL-10 concentrations compared with PL, calculated from 90% confidence intervals. Data analysis indicated that changes in circulating IL-10 concentrations (mean difference 0.86 pg路ml -1 ) were possibly greater (57%) for BA than PL. Results of this study suggest that 1 week of high-dose BA ingestion may enhance the anti-inflammatory response during intense military training, suggesting a potential therapeutic role of BA during intense training

    螔-Alanine Supplemented Diets Enhance Behavioral Resilience To Stress Exposure In An Animal Model Of Ptsd

    No full text
    Abstract This study investigated the effects of 尾-alanine (BA) ingestion on the behavioral and neuroendocrine response of post-traumatic stress disorder (PTSD) in a murine model. Animals were fed a normal diet with or without (PL) BA supplementation (100 mg kg-1) for 30 days. Animals were then exposed to a predator-scent stress (PSS) or a sham (UNEX). Behaviors were evaluated using an elevated plus maze (EPM) and acoustic startle response (ASR) 7 days following exposure to the PSS. Corticosterone concentrations (CS), expression of brain-derived neurotrophic factor (BDNF), and brain carnosine concentrations were analyzed a day later. Animals in PSS+PL spent significantly less time in the open arms and in the number of entries in the EPM than PSS+BA, UNEX+BA, or UNEX+PL. Animals in PSS+BA had comparable scores to UNEX+BA. Anxiety index was higher (p \u3c 0.05) in PSS+PL compared to PSS+BA or animals that were unexposed. ASR and freezing were greater (p \u3c 0.05) in animals exposed to PSS compared to animals unexposed. CS expression was higher (p \u3c 0.05) in animals exposed to PSS compared to unexposed animals. Brain carnosine concentrations in the hippocampus and other brain sections were significantly greater in animals supplemented with BA compared to PL. BDNF expression in the CA1 and DG subregions of the hippocampus was lower (p \u3c 0.05) in animals exposed and fed a normal diet compared to animals exposed and supplemented with BA, or animals unexposed. In conclusion, BA supplementation in rats increased brain carnosine concentrations and resulted in a reduction in PTSD-like behavior, which may be mediated in part by maintaining BDNF expression in the hippocampus

    beta-alanine supplementation improves tactical performance but not cognitive function in combat soldiers

    No full text
    Background: There are no known studies that have examined beta-alanine supplementation in military personnel. Considering the physiological and potential neurological effects that have been reported during sustained military operations, it appears that beta-alanine supplementation may have a potential benefit in maintaining physical and cognitive performance during high-intensity military activity under stressful conditions. The purpose of this study was to examine the effect of 28 days of beta-alanine ingestion in military personnel while fatigued on physical and cognitive performance. Methods: Twenty soldiers (20.1 +/- 0.9 years) from an elite combat unit were randomly assigned to either a beta-alanine ( BA) or placebo (PL) group. Soldiers were involved in advanced military training, including combat skill development, navigational training, self-defense/hand-to-hand combat and conditioning. All participants performed a 4-km run, 5-countermovement jumps using a linear position transducer, 120-m sprint, a 10-shot shooting protocol with assault rifle, including overcoming a misfire, and a 2-min serial subtraction test to assess cognitive function before (Pre) and after ( Post) 28 days of supplementation. Results: The training routine resulted in significant increases in 4-km run time for both groups, but no between group differences were seen (p = 0.597). Peak jump power at Post was greater for BA than PL (p = 0.034), while mean jump power for BA at Post was 10.2% greater (p = 0.139) than PL. BA had a significantly greater (p = 0.012) number of shots on target at Post (8.2 +/- 1.0) than PL (6.5 +/- 2.1), and their target engagement speed at Post was also significantly faster (p = 0.039). No difference in serial subtraction performance was seen between the groups (p = 0.844). Conclusion: Results of this study indicate that 4-weeks of beta-alanine ingestion in young, healthy soldiers did not impact cognitive performance, but did enhance power performance, marksmanship and target engagement speed from pre-ingestion levels
    corecore