The Effects of a Pre-exercise Feeding with or Without Fungal Carbohydrases (Carbogen™) on Blood Parameters and Exercise Performance in Elite Cyclists: A Preliminary Study

2002 ◽  
Vol 12 (3) ◽  
pp. 310-317 ◽  
Author(s):  
Laura Lewis Frank ◽  
Janine T. Baer ◽  
Charles P. Lambert ◽  
Mark L. Anderson
Keyword(s):  
Exercise Performance ◽  
Blood Parameters ◽  
Time Effect ◽  
Time To Exhaustion ◽  
Double Blind ◽  
Post Feeding ◽  
Competitive Cyclists ◽  
Preliminary Study ◽  
Elite Cyclists

The effect of fungal carbohydrases (Carbogen™ [C]) consumed with a meal replacement bar (MBR) on glucose metabolism and exercise performance was determined in 5 male competitive cyclists. After a 12-hour fast, subjects performed two 60-min cycling bouts at 80% V̇O2max followed by a time-to-exhaustion (TE) ride at 100% V̇O2max. One hour prior to each cycling bout, subjects ingested a MRB + 160-mg C or 160-mg CaCO3 placebo (PL) in a double-blind, counterbalanced fashion. Blood was drawn for determination of glucose, insulin, and lactate at: fasting, 1 hour post-feeding, minutes 30 and 60 of exercise, and after TE. Two-way ANOVA revealed a significant (p < .05) treatment and time effect for glucose, with C being higher than PL. Interaction effects were ob-· served for insulin and lactate. An increase in TE (min) at 100% V̇O2max was observed in the C versus PL trial (6.3 ± 3.4 vs. 4.4 ± 2.9, p < .001). A MRB+C may benefit cyclists due to increased BG and improved exercise performance.

scholarly journals Effects of pomegranate extract on blood flow and running time to exhaustion

2014 ◽  
Vol 39 (9) ◽  
pp. 1038-1042 ◽  
Author(s):  
Eric T. Trexler ◽  
Abbie E. Smith-Ryan ◽  
Malia N. Melvin ◽  
Erica J. Roelofs ◽  
Hailee L. Wingfield
Keyword(s):  
Blood Flow ◽  
Exercise Performance ◽  
Repeated Measures ◽  
Maximal Oxygen Consumption ◽  
Exercise Bout ◽  
Vessel Diameter ◽  
Time To Exhaustion ◽  
Double Blind ◽  
Beneficial Effects ◽  
Acute Ingestion

Recent research has shown that dietary nitrate has favorable effects on blood flow and exercise performance. The purpose of this randomized, double-blind, placebo-controlled crossover study was to investigate the acute effects of pomegranate extract on blood flow, vessel diameter, and exercise performance in active individuals. Nineteen men and women (mean ± SD: age, 22.2 ± 2.2 years; height, 174.8 ± 10.7 cm; body mass, 71.9 ± 13.5 kg) were randomly assigned to a placebo (PL) or pomegranate extract (PE) group. Participants performed a maximal oxygen consumption treadmill test to determine peak velocity (PV). Participants returned after 24–48 h and ingested either PL or PE. Brachial artery blood flow was assessed using ultrasound at baseline and 30 min post-ingestion (30minPI). Three treadmill runs to exhaustion were performed at 90%, 100%, and 110% PV. Blood flow was assessed immediately after each exercise bout and 30 min postexercise (30minPEx). After a 7–10 day washout, participants repeated the same procedures, ingesting the opposite supplement. Separate repeated measures ANOVAs were performed for blood flow, vessel diameter, and time to exhaustion (TTE). Blood flow was significantly augmented (p = 0.033) 30minPI with PE in comparison with PL. Vessel diameter was significantly larger (p = 0.036) 30minPEx with PE. Ingestion of PE was found to significantly augment TTE at 90% (p = 0.009) and 100% PV (p = 0.027). Acute ingestion of PE 30 min before exercise may enhance vessel diameter and blood flow and delay fatigue during exercise. Results of the current study indicate that PE is ergogenic for intermittent running, eliciting beneficial effects on blood flow.

Effect of carbohydrate mouth rinse on exercise performance in horses

2017 ◽  
Vol 13 (2) ◽  
pp. 79-86 ◽  
Author(s):  
P.M. Bogossian ◽  
M.L.T. Piffer ◽  
F.B. Maschietto ◽  
K.B. Bezerra ◽  
T. Oliveira ◽  
...  
Keyword(s):  
Exercise Performance ◽  
Water Solution ◽  
Lactate Concentration ◽  
Controlled Study ◽  
Time To Exhaustion ◽  
Mouth Rinse ◽  
Plasma Lactate ◽  
Double Blind ◽  
Plasma Lactate Concentration ◽  
The Mean

The mechanism related to the practice of oral carbohydrate (CHO) supplementation prior to intense exercise of a short duration (<30 min) for athletic horses remains unclear. Several studies in human athletes showed that the central nervous system played an important role in the enhancement of athletic performance due to CHO contact with undefined receptors in the oropharyngeal mucosa. This study aims to investigate the influence of CHO mouth rinse on the exercise performance of horses. In this double blind, randomised, placebo-controlled study, seven Mangalarga Marchador horses underwent a standardised exercise test (SET) in a field. The following protocols involving a single mouthwash (1 litre) had been used: a mouth rinse of 6.4% maltodextrin-water solution (CHO test), and a mouth rinse of only water solution (placebo test). The mean plasma lactate concentration immediately after SET (lactate peak) was higher in the CHO test (24.33±3.72 mmol/l) than in the placebo test (18.19±4.01 mmol/l), (P<0.001). No difference was observed in the mean time-to-exhaustion, mean and maximum heart rate, plasma glucose concentration and serum creatinine-kinase activity. Several studies described that there were improvements in the time-trial performance of cyclists and runners after a mouth rinse of CHO solution, whereas some did not. Carbohydrate mouth rinse had no influence on exercise performance in this study. Further investigations are required, as the significance of an increased plasma lactate concentration due to a CHO mouth rinse has yet to be elucidated.

scholarly journals The Effect of Kefir Supplementation on Improving Human Endurance Exercise Performance and Antifatigue

Metabolites ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 136
Author(s):  
Mon-Chien Lee ◽  
Wei-Lun Jhang ◽  
Chia-Chia Lee ◽  
Nai-Wen Kan ◽  
Yi-Ju Hsu ◽  
...  
Keyword(s):  
Placebo Group ◽  
Exercise Performance ◽  
Adverse Reactions ◽  
Dairy Product ◽  
Lactobacillus Species ◽  
Time To Exhaustion ◽  
Double Blind ◽  
Significant Difference ◽  
Kefir Grains ◽  
Lactate Levels

Kefir is an acidic, carbonated, and fermented dairy product produced by fermenting milk with kefir grains. The Lactobacillus species constitutes an important part of kefir grains. In a previous animal study, kefir effectively improved exercise performance and had anti-fatigue effects. The purpose of this research was to explore the benefits of applying kefir to improve exercise performance, reduce fatigue, and improve physiological adaptability in humans. The test used a double-blind crossover design and supplementation for 28 days. Sixteen 20–30 year-old subjects were divided into two groups in a balanced order according to each individual’s initial maximal oxygen uptake and were assigned to receive a placebo (equal flavor, equal calories, 20 g/day) or SYNKEFIR™ (20 g/day) every morning. After the intervention, there were 28 days of wash-out, during which time the subjects did not receive further interventions. After supplementation with SYNKEFIR™, the exercise time to exhaustion was significantly greater than that before ingestion (p = 0.0001) and higher than that in the Placebo group by 1.29-fold (p = 0.0004). In addition, compared with the Placebo group, the SYNKEFIR™ administration group had significantly lower lactate levels in the exercise and recovery (p < 0.05). However, no significant difference was observed in the changes in the gut microbiota. Although no significant changes in body composition were found, SYNKEFIR™ did not cause adverse reactions or harm to the participants’ bodies. In summary, 28 days of supplementation with SYNKEFIR™ significantly improved exercise performance, reduced the production of lactic acid after exercise, and accelerated recovery while also not causing any adverse reactions.

scholarly journals Breast Cancer Detection from a Urine Sample by Dog Sniffing: A Preliminary Study for the Development of a New Screening Device and a Literature Review

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 517
Author(s):  
Shoko Kure ◽  
Shinya Iida ◽  
Marina Yamada ◽  
Hiroyuki Takei ◽  
Naoyuki Yamashita ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Screening ◽  
Cancer Patients ◽  
Urine Sample ◽  
Urine Samples ◽  
Breast Cancer Patients ◽  
Double Blind ◽  
Blind Test ◽  
Preliminary Study ◽  
Detect Breast Cancer

Background: Breast cancer is a leading cause of cancer death worldwide. Several studies have demonstrated that dogs can sniff and detect cancer in the breath or urine sample of a patient. This study aims to assess whether the urine sample can be used for breast cancer screening by its fingerprints of volatile organic compounds using a single trained sniffer dog. This is a preliminary study for developing the “electronic nose” for cancer screening. Methods: A nine-year-old female Labrador Retriever was trained to identify cancer from urine samples of breast cancer patients. Urine samples from patients histologically diagnosed with primary breast cancer, those with non-breast malignant diseases, and healthy volunteers were obtained, and a double-blind test was performed. Total of 40 patients with breast cancer, 142 patients with non-breast malignant diseases, and 18 healthy volunteers were enrolled, and their urine samples were collected. Results: In 40 times out of 40 runs of a double-blind test, the trained dog could correctly identify urine samples of breast cancer patients. Sensitivity and specificity of this breast cancer detection method using dog sniffing were both 100%. Conclusions: The trained dog in this study could accurately detect breast cancer from urine samples of breast cancer patients. These results indicate the feasibility of a method to detect breast cancer from urine samples using dog sniffing in the diagnosis of breast cancer. Although the methodological standardization is still an issue to be discussed, the current result warrants further study for developing a new breast cancer screening method based on volatile organic compounds in urine samples.

scholarly journals Single Ingestion of Trehalose Enhances Prolonged Exercise Performance by Effective Use of Glucose and Lipid in Healthy Men

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1439
Author(s):  
Naomi Hamada ◽  
Tsuyoshi Wadazumi ◽  
Yoko Hirata ◽  
Mayumi Kuriyama ◽  
Kanji Watanabe ◽  
...  
Keyword(s):  
Exercise Performance ◽  
Prolonged Exercise ◽  
Insulin Response ◽  
Area Under The Curve ◽  
Constant Load ◽  
Bicycle Ergometer ◽  
The Body ◽  
Water Control ◽  
Double Blind ◽  
Healthy Men

Trehalose increases blood glucose levels slowly and induces a slight insulin response. The present study aimed to study the effect of trehalose on prolonged exercise performance. The participants were 12 healthy men (age: 21.3 ± 0.9 y). After an overnight fast (12 h), they first exercised with a constant load (intensity: 40% V˙O2peak) for 60 min using a bicycle ergometer. They continued to exercise with a constant load (40% V˙O2peak) for 30 min between four sets of the 30-s Wingate test. After the 1st set, each participant ingested 500 mL water (control), 8% glucose, or 8% trehalose in three trials. These three trials were at least one week apart and were conducted in a double-blind and randomized crossover manner. Blood was collected for seven biochemical parameters at 12 time points during the experiment. The area under the curve of adrenaline after ingestion of trehalose was significantly lower than that for water and tended to be lower than that for glucose in the later stage of the exercise. Lower secretion of adrenaline after a single dose of 8% trehalose during prolonged exercise reflected the preservation of carbohydrates in the body in the later stage of the exercise. In conclusion, a single ingestion of trehalose helped to maintain prolonged exercise performance.

scholarly journals Acute effect of high-definition and conventional tDCS on exercise performance and psychophysiological responses in endurance athletes: a randomized controlled trial

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Gomes da Silva Machado ◽  
Marom Bikson ◽  
Abhishek Datta ◽  
Egas Caparelli-Dáquer ◽  
Gozde Unal ◽  
...  
Keyword(s):  
Exercise Performance ◽  
Controlled Trial ◽  
Lower Limbs ◽  
Endurance Athletes ◽  
Test Reliability ◽  
Whole Body ◽  
Time To Exhaustion ◽  
Small Ring ◽  
High Definition ◽  
Psychophysiological Responses

AbstractTranscranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called “conventional” tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg−1 min−1) were enrolled in this single-center, randomized, crossover, and sham-controlled trial. To test reliability, participants performed two time to exhaustion (TTE) tests (control conditions) on a cycle simulator with 80% of peak power until volitional exhaustion. Next, they randomly received HD-tDCS (2.4 mA), conventional (2.0 mA), or active sham tDCS (2.0 mA) over the motor cortex for 20-min before performing the TTE test. TTE, heart rate (HR), associative thoughts, peripheral (lower limbs), and whole-body ratings of perceived exertion (RPE) were recorded every minute. Outcome measures were reliable. There was no difference in TTE between HD-tDCS (853.1 ± 288.6 s), simulated conventional (827.8 ± 278.7 s), sham (794.3 ± 271.2 s), or control conditions (TTE1 = 751.1 ± 261.6 s or TTE2 = 770.8 ± 250.6 s) [F(1.95; 21.4) = 1.537; P = 0.24; η2p = 0.123]. There was no effect on peripheral or whole-body RPE and associative thoughts (P > 0.05). No serious adverse effect was reported. A single session of neither HD-tDCS nor conventional tDCS changed exercise performance and psychophysiological responses in athletes, suggesting that a ceiling effect may exist.

Training-induced changes in muscle contraction patterns enhance exercise performance after short-term neuromuscular electrical stimulation

2020 ◽  
Vol 28 (4) ◽  
pp. 339-350
Author(s):  
Gökhan Umutlu ◽  
Nevzat Demirci ◽  
Nasuh Evrim Acar
Keyword(s):  
Electrical Stimulation ◽  
Muscle Contraction ◽  
Exercise Performance ◽  
Controlled Trial ◽  
Dynamic Control ◽  
Neuromuscular Electrical Stimulation ◽  
Interval Training ◽  
Time To Exhaustion ◽  
Muscle Strengthening ◽  
The Individual

BACKGROUND: Neuromuscular electrical stimulation (NMES) is a complementary tool for therapeutic exercise for muscle strengthening and may potentially enhance exercise performance. OBJECTIVE: To determine whether high-intensity interval training (HIIT) and continuous aerobic training (CA) coupled with NMES enhance the changes in the eccentric/concentric muscle contraction patterns of hamstring and quadriceps. METHODS: Forty-five healthy sedentary male participants performed cycling training 3 times per week for 8 weeks combined with/without NMES performed at a load equivalent to 65% and 120% of IVO2max (intensity associated with the achievement of maximal oxygen uptake). Anthropometrics, blood lactate measurements, IVO2max, TLimVO2max (time-to-exhaustion) and isokinetic strength parameters were measured at baseline and post-training using a randomized controlled trial. RESULTS: The conventional hamstring-to-quadriceps-ratio (HQR: Hcon/Qcon) at 60∘/s and the Dynamic Control Ratio (DCR: Hecc/Qcon) at 180∘/s significantly increased both in the dominant (D) and non-dominant (ND) limb in the HIIT + NMES group (p< 0.05). There was a positive significant correlation between the individual changes in D HQR at 60∘/s and IVO2max (r= 0.94, p= 0.005) and the DCR at 180∘/s and TLimVO2max (r= 0.90, p= 0.015), respectively. CONCLUSIONS: The increases in the eccentric muscle contraction and DCR following HIIT + NMES seem to improve fatigue tolerance, cause less fatigue and oxidative stress on the lower limb during pedaling at high intensities.

scholarly journals The Relationship between Resistance Exercise Performance and Ventilatory Efficiency after Beetroot Juice Intake in Well-Trained Athletes

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1094
Author(s):  
Noemí Serra-Payá ◽  
Manuel Vicente Garnacho-Castaño ◽  
Sergio Sánchez-Nuño ◽  
Lluís Albesa-Albiol ◽  
Montserrat Girabent-Farrés ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Exercise Test ◽  
Exercise Performance ◽  
Beetroot Juice ◽  
Experimental Conditions ◽  
Double Blind ◽  
Ventilatory Efficiency ◽  
End Tidal ◽  
Oxygen Uptake Efficiency Slope ◽  
The Relationship

The assessment of ventilatory efficiency is critical to understanding the matching of ventilation (VE) and perfusion in the lungs during exercise. This study aimed to establish a causal physiological relationship between ventilatory efficiency and resistance exercise performance after beetroot juice (BJ) intake. Eleven well-trained males performed a resistance exercise test after drinking 140 mL of BJ (~12.8 mmol NO3−) or a placebo (PL). Ventilatory efficiency was assessed by the VE•VCO2−1 slope, the oxygen uptake efficiency slope and the partial pressure of end-tidal carbon dioxide (PetCO2). The two experimental conditions were controlled using a randomized, double-blind crossover design. The resistance exercise test involved repeating the same routine twice, which consisted of wall ball shots plus a full squat (FS) with a 3 min rest or without a rest between the two exercises. A higher weight lifted was detected in the FS exercise after BJ intake compared with the PL during the first routine (p = 0.004). BJ improved the VE•VCO2−1 slope and the PetCO2 during the FS exercise in the first routine and at rest (p < 0.05). BJ intake improved the VE•VCO2−1 slope and the PetCO2 coinciding with the resistance exercise performance. The ergogenic effect of BJ could be induced under aerobic conditions at rest.

Establishment of an HPLC Method for Determination of Coumarin-3-Carboxylic Acid Analogues in Rat Plasma and a Preliminary Study on Their Pharmacokinetics

2021 ◽  
Author(s):  
Yan Xiong ◽  
Yong-Hong Liu ◽  
Jian-Sha Li ◽  
Yu-Ying Zhang ◽  
Jing Zhang ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Carboxylic Acid ◽  
High Performance ◽  
Rat Plasma ◽  
Hplc Method ◽  
Array Detector ◽  
Pharmacokinetic Parameters ◽  
Preliminary Study

Abstract A simple high performance liquid chromatography (HPLC) method was developed and validated for the determination of coumarin-3-carboxylic acid analogues (C3AA) in rat plasma and a preliminary study on pharmacokinetics. Ferulic acid (FA) was used as the internal standard substance, and coumarin-3-carboxylic acid (C3A) was used as a substitute for quantitative C3AA. After protein precipitation with methanol, the satisfactory separation was achieved on an ODS2 column when the temperature was maintained at 30 ± 2°C. The correlation coefficient r in the C3A linear equation is equal to 0.9990. Pharmacokinetic parameters for t1/2, Tmax, Cmax, area under the curve (AUC)0-t, average residence time (MRT), apparent volume of distribution (V z/F) and clearance (Cl/F) were 1.89 ± 0.03 h, 0.39 ± 0.14 h, 1.81 ± 0.10 g· mL−1 ·h, 7.88 ± 0.24 g·mL−1·h, 3.23 ± 0.14 h, 0.43 ± 0.03 (mg·kg−1)·(g·mL−1)−1·h−1, respectively. The high performance liquid chromatography-photo diode array detector (HPLC-PDA) method established in this study can be used to separate and determine the content of C3AA in plasma of rats after 60% ethanol extraction by gavage. The plasma concentration-time curve and pharmacokinetic parameters reflect the absorption of C3AA in rat blood after oral administration to some extent.

Direct radioimmunoassay of 6-sulfatoxymelatonin in plasma with use of an iodinated tracer

1991 ◽  
Vol 37 (4) ◽  
pp. 536-539 ◽  
Author(s):  
Catherine Harthé ◽  
Bruno Claustrat ◽  
Jocelyne Brun ◽  
Guy Chazot
Keyword(s):  
Plasma Sample ◽  
Limit Of Detection ◽  
Circadian Variation ◽  
Hepatic Metabolism ◽  
Pharmaceutical Formulations ◽  
Practical Application ◽  
Bovine Serum Albumin Conjugate ◽  
Preliminary Study ◽  
Related Compounds

Abstract We describe here a direct a radioimmunoassay (RIA) for the determination of 6-sulfatoxymelatonin (aMT6s) in plasma, with iodinated aMT6s as tracer. The aMT6s antiserum was raised in rabbit by immunization with a bovine serum albumin conjugate, giving negligible cross-reactivities for related compounds. The low limit of detection (15 pmol/L) allowed a direct assay that required only a 100-microL plasma sample. Dilutions of plasma and of synthetic aMT6s gave the same parallel response in the RIA. A preliminary study showed a circadian variation in healthy volunteers, with mean concentrations ranging from 52 (at 1600-2100 h) to 378 pmol/L (at 0400 h), whereas this rhythm was abolished in pinealomectomized patients. After administration of melatonin orally, or by infusion, the aMT6s concentrations in plasma concorded with previous data on aMT6s production and pharmacokinetics, with aMT6s being cleared from plasma more slowly than melatonin. This assay should have practical application in the development of new pharmaceutical formulations that minimize the hepatic metabolism of melatonin.

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