Pseudoephedrine is without ergogenic effects during prolonged exercise

1996 ◽  
Vol 81 (6) ◽  
pp. 2611-2617 ◽  
Author(s):  
Hunter Gillies ◽  
Wayne E. Derman ◽  
Timothy D. Noakes ◽  
Peter Smith ◽  
Alicia Evans ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
High Intensity ◽  
Muscle Function ◽  
Prolonged Exercise ◽  
Peak Plasma ◽  
Plasma Concentrations ◽  
High Intensity Exercise ◽  
Double Blind ◽  
Drug Concentrations ◽  
Ergogenic Effects

Gillies, Hunter, Wayne E. Derman, Timothy D. Noakes, Peter Smith, Alicia Evans, and Gary Gabriels.Pseudoephedrine is without ergogenic effects during prolonged exercise. J. Appl. Physiol. 81(6): 2611–2617, 1996.—This study was designed to measure whether a single dose of 120 mg pseudoephedrine ingested 120 min before exercise influences performance during 1 h of high-intensity exercise. The effects of exercise on urinary excretion of the drug were also studied. Ten healthy male cyclists were tested on two occasions, separated by at least 7 days, by using a randomly assigned, double-blind, placebo-controlled, crossover design. Exercise performance was tested during a 40-km trial on a laboratory cycle ergometer, and skeletal muscle function was measured during isometric contractions. On a third occasion, subjects ingested 120 mg pseudoephedrine but did not exercise [control (C)]. Pseudoephedrine did not influence either time trial performance [drug (D) vs. placebo: 58.1 ± 1.4 (SE) vs. 58.7 ± 1.5 min] or isometric muscle function. Urinary pseudoephedrine concentrations were significantly increased 1 h after exercise (D vs. C: 114.3 ± 27.2 vs. 35.4 ± 13.1 μg/ml; P < 0.05). Peak plasma pseudoephedrine concentrations ( P < 0.05) but not time taken to reach peak plasma concentrations or the area under the plasma pseudoephedrine concentration vs. time curve was significantly increased in the total group with exercise (D vs. C). In three subjects, plasma pseudoephedrine concentrations were not influenced by exercise. Only these subjects showed increased urinary pseudoephedrine excretion during exercise. We conclude that a single therapeutic dose of pseudoephedrine did not have a measurable ergogenic effect during high-intensity exercise of 1-h duration, but plasma drug concentrations and urinary excretion were altered by exercise. These findings have practical relevance to doping control regulations in international sporting competitions.

Anaerobic Power Responses to Amino Acid Nutritional Supplementation

1991 ◽  
Vol 1 (4) ◽  
pp. 366-377 ◽  
Author(s):  
Carl M. Maresh ◽  
Catherine L. Gabaree ◽  
Jay R. Hoffman ◽  
Daniel R. Hannon ◽  
Michael R. Deschenes ◽  
...  
Keyword(s):  
Exercise Performance ◽  
High Intensity ◽  
Peak Plasma ◽  
Anaerobic Power ◽  
High Intensity Exercise ◽  
Control Measures ◽  
Plasma Lactate ◽  
Mean Power ◽  
Exercise Tests ◽  
Double Blind

To examine the effect of a nutritional supplement (ATP-E™) on high intensity exercise performance, 23 physically active males volunteered to perform six Wingate Anaerobic Power tests. Tests were performed prior to and at 14 and 21 days during ATP-E~o~r placebo ingestion. f i e experiment followed a double-blind and random-order design. Twelve subjects (responders, R) showed an increase in preexercise blood ATP on Day 14 of ATP-E™ ingestion compared to control measures. The remaining 11 subjects (nonresponders, NR) had no change in pree~e~cibselo od ATP. Peak power and mean power were unchanged for both R and NR subjects across the exercise tests, but R experienced a decrease (p< 0.05) in immediate postexercise plasma lactate on Day 14 of ATP-E™ testing compared to their control measures. NR had no change in peak plasma lactate at any time during the study. The results suggest that short-term high intensity exercise performance was maintained in R with less reliance on anaerobic metabolism, and that response was evident following 14 days of ATP-E™ ingestion.

Blood Flow Restriction Training Applied With High-Intensity Exercise Does Not Improve Quadriceps Muscle Function After Anterior Cruciate Ligament Reconstruction: A Randomized Controlled Trial

2020 ◽  
Vol 48 (4) ◽  
pp. 825-837 ◽  
Author(s):  
Michael T. Curran ◽  
Asheesh Bedi ◽  
Christopher L. Mendias ◽  
Edward M. Wojtys ◽  
Megan V. Kujawa ◽  
...  
Keyword(s):  
Muscle Strength ◽  
High Intensity ◽  
Muscle Function ◽  
Controlled Trial ◽  
Cruciate Ligament ◽  
Quadriceps Muscle ◽  
High Intensity Exercise ◽  
Quadriceps Muscle Strength ◽  
Flow Restriction ◽  
Anterior Cruciate

Background: A major goal of rehabilitation after anterior cruciate ligament reconstruction (ACLR) is restoring quadriceps muscle strength. Unfortunately, current rehabilitation paradigms fall short of this goal, such that substantial quadriceps muscle strength deficits can limit return to play and increase the risk of recurrent injuries. Blood flow restriction training (BFRT) involves the obstruction of venous return to working muscles during exercise and may lead to better recovery of quadriceps muscle strength after ACLR. Purpose: To examine the efficacy of BFRT with high-intensity exercise on the recovery of quadriceps muscle function in patients undergoing ACLR. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A total of 34 patients (19 female, 15 male; mean age, 16.5 ± 2.7 years; mean height, 169.0 ± 19.7 cm; mean weight, 73.2 ± 17.7 kg) scheduled to undergo ACLR were randomly assigned to 1 of 4 groups: concentric (n = 8), eccentric (n = 8), concentric with BFRT (n = 9), and eccentric with BFRT (n = 9). The exercise component of the intervention consisted of patients performing a single-leg isokinetic leg press, at an intensity of 70% of the patients’ 1-repetition maximum during either the concentric or eccentric action, for 4 sets of 10 repetitions 2 times per week for 8 weeks beginning at 10 weeks postoperatively. Patients randomized to the BFRT groups performed the leg-press exercise with a cuff applied to the thigh, set to a limb occlusion pressure of 80%. Isometric and isokinetic (60 deg/s) quadriceps peak torque, quadriceps muscle activation, and rectus femoris muscle volume were assessed before ACLR, after BFRT, and at the time that patients returned to activity and were converted to the change in values from baseline for analysis. Also, 1-way analyses of covariance were used to compare the change in values for each dependent variable between groups after BFRT and at return to activity ( P ≤ .05). Results: No significant differences were found between groups for any outcome measures at either time point ( P > .05). Conclusion: An 8-week BFRT plus high-intensity exercise intervention did not significantly improve quadriceps muscle strength, activation, or volume. On the basis of our findings, the use of BFRT in conjunction with high-intensity resistance exercise in patients undergoing ACLR to improve quadriceps muscle function may not be warranted. Registration: NCT03141801 ( ClinicalTrials.gov identifier)

Failure of Glycine-Arginine-α-Ketoisocaproic Acid to Improve High-Intensity Exercise Performance in Trained Cyclists

2011 ◽  
Vol 21 (1) ◽  
pp. 33-39 ◽  
Author(s):  
Lukas Beis ◽  
Yaser Mohammad ◽  
Chris Easton ◽  
Yannis P. Pitsiladis
Keyword(s):  
Exercise Performance ◽  
High Intensity ◽  
Perceived Exertion ◽  
Cycle Ergometer ◽  
High Intensity Exercise ◽  
Ratings Of Perceived Exertion ◽  
Mean Power ◽  
Double Blind ◽  
Oral Supplementation ◽  
Experimental Trials

Oral supplementation with glycine-arginine-α-ketoisocaproic acid (GAKIC) has previously been shown to improve exhaustive high-intensity exercise performance. There are no controlled studies involving GAKIC supplementation in well-trained subjects. The aim of the current study was to examine the effects of GAKIC supplementation on fatigue during high-intensity, repeated cycle sprints in trained cyclists. After at least 2 familiarization trials, 10 well-trained male cyclists completed 2 supramaximal sprint tests each involving 10 sprints of 10 s separated by 50-s rest intervals on an electrically braked cycle ergometer. Subjects ingested 11.2 g of GAKIC or placebo (Pl) during a period of 45 min before the 2 experimental trials, administered in a randomized and double-blind fashion. Peak power declined from the 1st sprint (M ± SD; Pl 1,332 ± 307 W, GAKIC 1,367 ± 342 W) to the 10th sprint (Pl 1,091 ± 229 W, GAKIC 1,061 ± 272 W) and did not differ between conditions (p = .88). Mean power declined from the 1st sprint (Pl 892 ± 151 W, GAKIC 892 ± 153 W) to the 10th sprint (Pl 766 ± 120 W, GAKIC 752 ± 138 W) and did not differ between conditions (p = .96). The fatigue index remained at ~38% throughout the series of sprints and did not differ between conditions (p = .99). Heart rate and ratings of perceived exertion increased from the 1st sprint to the 10th sprint and did not differ between conditions (p = .11 and p = .83, respectively). In contrast to previous studies in untrained individuals, these results suggest that GAKIC has no ergogenic effect on repeated bouts of high-intensity exercise in trained individuals.

The pharmacokinetics of azacitidine following subcutaneous treatment in patients with myelodysplastic syndromes (MDS) or acute myelogenous leukemia (AML)

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 7087-7087
Author(s):  
E. Laille ◽  
R. Ward ◽  
A. Nasser ◽  
M. Stoltz ◽  
C. Cogle ◽  
...  
Keyword(s):  
Peak Plasma ◽  
Plasma Concentrations ◽  
Hepatic Metabolism ◽  
Volume Of Distribution ◽  
Adverse Event Reporting ◽  
Myelogenous Leukemia ◽  
Minor Role ◽  
Renal Elimination ◽  
Drug Concentrations ◽  
A Minor

7087 Background: 5-azacitidine (AZA), through its effects on DNA metabolism, gene expression, and cell differentiation, has proven beneficial in treatment of MDS and AML and AZA therapy significantly increases survival in higher-risk MDS and AML compared to conventional care. Few studies have evaluated the pharmacokinetics (PK) of AZA and the renal elimination of AZA has not been previously published to our knowledge. Plasma PK of AZA are herein reported in patients receiving SC doses of 75 mg/m2. This study was designed to also assess the contribution of renal elimination to the overall clearance of AZA. Methods: Adult patients with MDS or AML and ECOG status 0–2 were treated with 7 consecutive daily SC doses of 75 mg/m2 AZA during their first treatment cycle. PK parameters of AZA were derived from drug concentrations in plasma and urine collected after the first and last dose (day 7) of AZA. Safety was evaluated by adverse event reporting (NCI-CTC). Results: Currently, 18 patients have been treated with SC AZA. AZA was rapidly absorbed and reached peak plasma concentrations (concs) within 0.5 hr post dosing. The AUCinf after SC doses was 1170 hr*ng/mL. The AZA concs declined in a pseudo bi-phasic manner with an elimination half-life of 1.25 hours. The plasma PK profiles after the first and last dose were superimposable. The apparent total clearance (CL/F) and volume of distribution (Vd/F) were 143 L/hr and 318 L, respectively. AZA recovery in urine was very small relative to dose (<2%). AZA was well tolerated and no unexpected toxicities were observed. Conclusions: The AZA AUCinf after SC doses is similar to the published AUC value (1044 hr*ng/mL) after 75 mg/m2 IV doses indicating approximating 100% systemic bioavailability. After SC dosing, CL/F exceeded hepatic blood flow indicating extra-hepatic metabolism. Vd/F was 4–5 fold greater than total body water suggesting extensive AZA tissue distribution. Renal elimination appears to play a minor role in the overall clearance of AZA. [Table: see text]

Gastrointestinal Discomfort during Intermittent High-Intensity Exercise: Effect of Carbohydrate–Electrolyte Beverage

2004 ◽  
Vol 14 (6) ◽  
pp. 673-683 ◽  
Author(s):  
Xiaocai Shi ◽  
Mary K. Horn ◽  
Kris L. Osterberg ◽  
John R. Stofan, ◽  
Jeffrey J. Zachwieja ◽  
...  
Keyword(s):  
Randomized Trial ◽  
High Intensity ◽  
High Intensity Exercise ◽  
Double Blind ◽  
Stomach Upset ◽  
Cumulative Index ◽  
Carbohydrate Concentration ◽  
Gastrointestinal Discomfort ◽  
Exercise Effect ◽  
Vertical Jumps

This study investigated whether different beverage carbohydrate concentration and osmolality would provoke gastrointestinal (GI) discomfort during intermittent, high-intensity exercise. Thirty-six adult and adolescent athletes were tested on separate days in a double-blind, randomized trial of 6% and 8% carbohydrate-electrolytes (CHO-E) beverages during four 12-min quarters (Q) of circuit training that included intermittent sprints, lateral hops, shuttle runs, and vertical jumps. GI discomfort and fatigue surveys were completed before the first Q and immediately after each Q. All ratings of GI discomfort were modest throughout the study. The cumulative index for GI discomfort, however, was greater for the 8% CHO-E beverage than for the 6% CHO-E beverage at Q3 and Q4 (P < 0.05). Averaging across all 4 quarters, the 8% CHO-E treatment produced significantly higher mean ratings of stomach upset and side ache. In conclusion, higher CHO concentration and osmolality in an ingested beverage provokes stomach upset and side ache.

Does low serum carnosinase activity favor high-intensity exercise capacity?

2014 ◽  
Vol 116 (5) ◽  
pp. 553-559 ◽  
Author(s):  
Audrey Baguet ◽  
Inge Everaert ◽  
Benito Yard ◽  
Verena Peters ◽  
Johannes Zschocke ◽  
...  
Keyword(s):  
High Intensity ◽  
Genetic Selection ◽  
High Intensity Exercise ◽  
Acid Base Balance ◽  
Acid Base ◽  
Long Distance ◽  
Double Blind ◽  
Maximal Power Output ◽  
Cross Sectional ◽  
Base Balance

Given the ergogenic properties of β-alanyl-L-histidine (carnosine) in skeletal muscle, it can be hypothesized that elevated levels of circulating carnosine could equally be advantageous for high-intensity exercises. Serum carnosinase (CN1), the enzyme hydrolyzing the dipeptide, is highly active in the human circulation. Consequently, dietary intake of carnosine usually results in rapid degradation upon absorption, yet this is less pronounced in subjects with low CN1 activity. Therefore, acute carnosine supplementation before high-intensity exercise could be ergogenic in these subjects. In a cross-sectional study, we determined plasma CN1 activity and content in 235 subjects, including 154 untrained controls and 45 explosive and 36 middle- to long-distance elite athletes. In a subsequent double-blind, placebo-controlled, crossover study, 12 men performed a cycling capacity test at 110% maximal power output (CCT 110%) following acute carnosine (20 mg/kg body wt) or placebo supplementation. Blood samples were collected to measure CN1 content, carnosine, and acid-base balance. Both male and female explosive athletes had significantly lower CN1 activity (14% and 21% lower, respectively) and content (30% and 33% lower, respectively) than controls. Acute carnosine supplementation resulted only in three subjects in carnosinemia. The CCT 110% performance was not improved after carnosine supplementation, even when accounting for low/high CN1 content. No differences were found in acid-base balance, except for elevated resting bicarbonate following carnosine supplementation and in low CN1 subjects. In conclusion, explosive athletes have lower serum CN1 activity and content compared with untrained controls, possibly resulting from genetic selection. Acute carnosine supplementation does not improve high-intensity performance.

Does photobiomodulation therapy is better than cryotherapy in muscle recovery after a high-intensity exercise? A randomized, double-blind, placebo-controlled clinical trial

2017 ◽  
Vol 32 (2) ◽  
pp. 429-437 ◽  
Author(s):  
Thiago De Marchi ◽  
Vinicius Mazzochi Schmitt ◽  
Guilherme Pinheiro Machado ◽  
Juliane Souza de Sene ◽  
Camila Dallavechia de Col ◽  
...  
Keyword(s):  
Clinical Trial ◽  
High Intensity ◽  
Photobiomodulation Therapy ◽  
High Intensity Exercise ◽  
Controlled Clinical Trial ◽  
Muscle Recovery ◽  
Double Blind ◽  
Double Blind Placebo ◽  
Better Than

The Effect of Sodium Bicarbonate Supplementation on the Decline in Gross Efficiency During a 2000-m Cycling Time Trial

2020 ◽  
Vol 15 (5) ◽  
pp. 741-747 ◽  
Author(s):  
Anna E. Voskamp ◽  
Senna van den Bos ◽  
Carl Foster ◽  
Jos J. de Koning ◽  
Dionne A. Noordhof
Keyword(s):  
Sodium Bicarbonate ◽  
High Intensity ◽  
Lactate Concentration ◽  
Time Trial ◽  
High Intensity Exercise ◽  
Concentration Data ◽  
Double Blind ◽  
Cycling Time Trial ◽  
Gross Efficiency ◽  
Cycling Time

Background: Gross efficiency (GE) declines during high-intensity exercise. Increasing extracellular buffer capacity might diminish the decline in GE and thereby improve performance. Purpose: To examine if sodium bicarbonate (NaHCO3) supplementation diminishes the decline in GE during a 2000-m cycling time trial. Methods: Sixteen male cyclists and 16 female cyclists completed 4 testing sessions including a maximal incremental test, a familiarization trial, and two 2000-m GE tests. The 2000-m GE tests were performed after ingestion of either NaHCO3 supplements (0.3 g/kg body mass) or placebo supplements (amylum solani, magnesium stearate, and sunflower oil capsules). The GE tests were conducted using a double-blind, randomized, crossover design. Power output, gas exchange, and time to complete the 2000-m time trials were recorded. Capillary blood samples were analyzed for blood bicarbonate, pH, and lactate concentration. Data were analyzed using magnitude-based inference. Results: The decrement in GE found after the 2000-m time trial was possibly smaller in the male and female groups after NaHCO3 than with placebo ingestion, with the effect in both groups combined being unclear. The effect on performance was likely trivial for males (placebo 164.2 [5.0] s, NaHCO3 164.3 [5.0] s; Δ0.1; ±0.6%), unclear for females (placebo 178.6 [4.8] s, NaHCO3 178.0 [4.3] s; Δ−0.3; ±0.5%), and very likely trivial when effects were combined. Blood bicarbonate, pH, and lactate concentration were substantially elevated from rest to pretest after NaHCO3 ingestion. Conclusions: NaHCO3 supplementation results in an unclear effect on the decrease in GE during high-intensity exercise and in a very likely trivial effect on performance.

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