Dose Effect of Caffeine on Testosterone and Cortisol Responses to Resistance Exercise

2008 ◽  
Vol 18 (2) ◽  
pp. 131-141 ◽  
Author(s):  
C. Martyn Beaven ◽  
Will G. Hopkins ◽  
Kier T. Hansen ◽  
Matthew R. Wood ◽  
John B. Cronin ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Random Order ◽  
Acute Effect ◽  
Rugby League ◽  
Dose Effect ◽  
Exercise Session ◽  
Dependent Manner ◽  
Double Blind ◽  
Caffeine Ingestion ◽  
Testosterone Concentration

Introduction:Interest in the use of caffeine as an ergogenic aid has increased since the International Olympic Committee lifted the partial ban on its use. Caffeine has beneficial effects on various aspects of athletic performance, but its effects on training have been neglected.Purpose:To investigate the acute effect of caffeine on the exercise-associated increases in testosterone and cortisol in a double-blind crossover study.Methods:Twenty-four professional rugby-league players ingested caffeine doses of 0, 200, 400, and 800 mg in random order 1 hr before a resistance-exercise session. Saliva was sampled at the time of caffeine ingestion, at 15-min intervals throughout each session, and 15 and 30 min after the session. Data were log-transformed to estimate percent effects with mixed modeling, and effects were standardized to assess magnitudes.Results:Testosterone concentration showed a small increase of 15% (90% confidence limits, ± 19%) during exercise. Caffeine raised this concentration in a dose-dependent manner by a further small 21% (± 24%) at the highest dose. The 800-mg dose also produced a moderate 52% (± 44%) increase in cortisol. The effect of caffeine on the testosterone:cortisol ratio was a small decline (14%; ± 21%).Conclusion:Caffeine has some potential to benefit training outcomes via the anabolic effects of the increase in testosterone concentration, but this benefit might be counteracted by the opposing catabolic effects of the increase in cortisol and resultant decline in the testosterone:cortisol ratio.

scholarly journals Caffeine Does Not Augment Markers of Muscle Damage or Leukocytosis Following Resistance Exercise

2010 ◽  
Vol 5 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Marco Machado ◽  
Alexander J. Koch ◽  
Jeffrey M. Willardson ◽  
Frederico C. dos Santos ◽  
Victor M. Curty ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Muscle Damage ◽  
Leukocyte Count ◽  
Total Leukocyte Count ◽  
Exercise Session ◽  
Caffeine Ingestion ◽  
Resistance Exercise Session

Purpose:The purpose of this study was to evaluate the effects of caffeine ingestion before a resistance exercise session on markers of muscle damage (CK, LDH, ALT, AST) and leukocyte levels.Methods:Fifteen soccer athletes completed two resistance exercise sessions that differed only in the ingestion of caffeine or a placebo preworkout.Results:CK concentration increased significantly following the caffeine session (415.8 ± 62.8 to 542.0 ± 73.5) and the placebo session (411.5 ± 43.3 to 545.8 ± 59.9), with no significant differences between sessions. Similarly, LDH concentration increased significantly following the caffeine session (377.5 ± 18.0 to 580.5 ± 36.1) and the placebo session (384.8 ± 13.9 to 570.4 ± 36.1), with no significant differences between sessions. Both sessions resulted in significant increases in the total leukocyte count (caffeine = 6.24 ± 2.08 to 8.84 ± 3.41; placebo = 6.36 ± 2.34 to 8.77 ± 3.20), neutrophils (caffeine = 3.37 ± 0.13 to 5.15 ± 0.28; placebo = 3.46 ± 0.17 to 5.12 ± 0.24), lymphocytes (caffeine = 2.19 ± 0.091 to 2.78 ± 0.10; placebo = 2.17 ± 0.100 to 2.75 ± 0.11), and monocytes (caffeine = 0.53 ± 0.02 to 0.72 ± 0.06; placebo = 0.56 ± 0.03 to 0.69 ± 0.04), with no significant differences between sessions.Conclusion:Ingestion of caffeine at 4.5 mg⋅kg-1 did not augment markers of muscle damage or leukocyte levels above that which occurs through resistance exercise alone.

scholarly journals A Combination of Amino Acids and Caffeine Enhances Sprint Running Capacity in a Hot, Hypoxic Environment

2016 ◽  
Vol 26 (1) ◽  
pp. 33-45 ◽  
Author(s):  
Tom R. Eaton ◽  
Aaron Potter ◽  
François Billaut ◽  
Derek Panchuk ◽  
David B. Pyne ◽  
...  
Keyword(s):  
Muscle Activation ◽  
Near Infrared ◽  
Cerebral Oxygenation ◽  
Team Sport ◽  
Exercise Session ◽  
Emg Activity ◽  
Double Blind ◽  
Caffeine Ingestion ◽  
Sprint Running ◽  
Hypoxic Environment

Heat and hypoxia exacerbate central nervous system (CNS) fatigue. We therefore investigated whether essential amino acid (EAA) and caffeine ingestion attenuates CNS fatigue in a simulated team sport–specific running protocol in a hot, hypoxic environment. Subelite male team sport athletes (n = 8) performed a repeat sprint running protocol on a nonmotorized treadmill in an extreme environment on 4 separate occasions. Participants ingested one of four supplements: a double placebo, 3 mg.kg-1 body mass of caffeine + placebo, 2 × 7 g EAA (Musashi Create)+placebo, or caffeine + EAA before each exercise session using a randomized, double-blind crossover design. Electromyography (EMG) activity and quadriceps evoked responses to magnetic stimulation were assessed from the dominant leg at preexercise, halftime, and postexercise. Central activation ratio (CAR) was used to quantify completeness of quadriceps activation. Oxygenation of the prefrontal cortex was measured via near-infrared spectroscopy. Mean sprint work was higher (M = 174 J, 95% CI [23, 324], p < .05, d = 0.30; effect size, likely beneficial) in the caffeine + EAA condition versus EAAs alone. The decline in EMG activity was less (M = 13%, 95% CI [0, 26]; p < .01, d = 0.58, likely beneficial) in caffeine + EAA versus EAA alone. Similarly, the pre- to postexercise decrement in CAR was significantly less (M = −2.7%, 95% CI [0.4, 5.4]; p < .05, d = 0.50, likely beneficial) when caffeine + EAA were ingested compared with placebo. Cerebral oxygenation was lower (M = −5.6%, 95% CI [1.0, 10.1]; p < .01, d = 0.60, very likely beneficial) in the caffeine + EAA condition compared with LNAA alone. Coingestion of caffeine and EAA appears to maintain muscle activation and central drive, with a small improvement in running performance.

scholarly journals Chronic capsiate supplementation increases fat-free mass and upper body strength but not the inflammatory response to resistance exercise in young untrained men: a randomized, placebo-controlled and double-blind study

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Vilton Emanoel Lopes de Moura e Silva ◽  
Jason Michael Cholewa ◽  
Ralf Jäger ◽  
Nelo Eidy Zanchi ◽  
Marcelo Conrado de Freitas ◽  
...  
Keyword(s):  
Resistance Training ◽  
Inflammatory Response ◽  
Resistance Exercise ◽  
Fat Free Mass ◽  
Upper Body ◽  
Exercise Session ◽  
Double Blind ◽  
Body Strength ◽  
Upper Body Strength ◽  
And Performance

Abstract Background Acute capsaicinoid and capsinoid supplementation has endurance and resistance exercise benefits; however, if these short-term performance benefits translate into chronic benefits when combined with resistance training is currently unknown. This study investigated changes of chronic Capsiate supplementation on muscular adaptations, inflammatory response and performance in untrained men. Methods Twenty untrained men were randomized to ingest 12 mg Capsiate (CAP) or placebo in a parallel, double-blind design. Body composition and performance were measured at pre-training and after 6 weeks of resistance training. An acute resistance exercise session test was performed pre and post-intervention. Blood samples were collected at rest and post-resistance exercise to analyze Tumor necrosis factor- (TNF-), Soluble TNF- receptor (sTNF-r), Interleukin-6 (IL-6) and Interleukin-10 (IL-10). Results Exercise and CAP supplementation increased fat-free mass in comparison to baseline by 1.5 kg (P < 0.001), however, the majority of the increase (1.0 kg) resulted from an increase in total body water. The CAP change scores for fat-free mass were significantly greater in comparison to the placebo (CAP ∆%= 2.1 ± 1.8 %, PLA ∆%= 0.7 ± 1.3 %, P = 0.043) and there was a significant difference between groups in the bench press exercise (P = 0.034) with greater upper body strength change score for CAP (∆%= 13.4 ± 9.1 %) compared to placebo (∆%= 5.8 ± 5.2 %), P = 0.041. CAP had no effect on lower body strength and no supplementation interactions were observed for all cytokines in response to acute resistance exercise (P > 0.05). Conclusion Chronic Capsiate supplementation combined with resistance training during short period (6 weeks) increased fat-free mass and upper body strength but not inflammatory response and performance in young untrained men.

Acute effect of a resistance exercise session on markers of cartilage breakdown and inflammation in women with rheumatoid arthritis

2017 ◽  
Vol 20 (11) ◽  
pp. 1704-1713 ◽  
Author(s):  
Ana Carolina Pereira Nunes Pinto ◽  
Jamil Natour ◽  
Charlles Heldan de Moura Castro ◽  
Marina Eloi ◽  
Império Lombardi Junior
Keyword(s):  
Rheumatoid Arthritis ◽  
Resistance Exercise ◽  
Acute Effect ◽  
Exercise Session ◽  
Cartilage Breakdown ◽  
Resistance Exercise Session

scholarly journals Dose Effect of Caffeine Ingestion on Cardiac Parasympathetic Reactivation Following an Acute Bout of Anaerobic Performance Exercise in Recreational Athletes

2020 ◽  
Author(s):  
Amir Sarshin ◽  
Alireza Naderi ◽  
Carlos Janssen Gomes da Cruz ◽  
Foad Feizolahi ◽  
Scott C. Forbes ◽  
...  
Keyword(s):  
Anaerobic Exercise ◽  
Dose Effect ◽  
Secondary Outcome ◽  
Autonomic Reactivity ◽  
Double Blind ◽  
Caffeine Ingestion ◽  
Post Exercise ◽  
Recreational Athletes ◽  
Parasympathetic Reactivation ◽  
Post Exercise Recovery

Abstract Background: To examine the dose effects of caffeine ingestion on autonomic reactivation following anaerobic exercise. Methods: Recreationally active males (N=20; 24±2y) participated in a randomized, double-blind, placebo-controlled, crossover study where participants ingested: (1) Control (CON; no supplement), (2) a non-caffeinated placebo (PLA), (3) 3-mg∙kg-1 of caffeine (CAF3) or (4) 6-mg∙kg-1 of caffeine (CAF6) prior to a Wingate testing. Parasympathetic (lnRMSSD, primary outcome) and global HRV (lnSDNN, secondary outcome) were assessed at rest (i.e., pre-ingestion), 45-min post-ingestion, and 5-min and 35-min post-exercise recovery. We used a GLM to assess mean (95% CI) changes from pre-ingestion baseline.Results: Overall, we observed a significant trend for lnRMSSD and lnSDNN (both, p=0.001, ηp2=0.745). Forty-five minutes after treatment ingestion, we observed a significant increase in lnRMSSD for CAF3 (0.15ms, 95%CI, 0.07,0.24) and CAF6 (0.16ms, 95%CI, 0.06,0.25), both being significant (both, p<0.004) vs. CON (-0.02ms, 95%CI, -0.09,0.04). Five-minutes after exercise, all treatments demonstrated significant declines in lnRMSSD vs. baseline (all, p<0.001). After 35-min of recovery, lnRMSSD returned to a levels not significantly different than baseline for CAF3 (0.03ms, 95%CI, -0.05, 0.12) and CAF6 (-0.03ms, 95%CI, -0.17, 0.10), while PLA (-0.16ms, 95%CI, -0.25, -0.06) and CON (-0.17ms, 95%CI, -0.28, -0.07) treatments remained significantly depressed. A similar pattern was also observed for SDNNConclusion: Caffeine ingestion increases resting cardiac autonomic modulation and accelerates post-exercise autonomic recovery after a bout of anaerobic exercise test in recreationally active young men. However, no differences between caffeine doses on cardiac autonomic reactivity were observed.

Acute effect of resistance exercise on cognitive function in people living with HIV

2020 ◽  
pp. 095646242095857
Author(s):  
Dayane C de Souza ◽  
Wagner JR Domingues ◽  
Kauana B Marchini ◽  
Pollyana M Nunhes ◽  
Alesandro Garcia ◽  
...  
Keyword(s):  
Cognitive Function ◽  
Resistance Exercise ◽  
Acute Effect ◽  
Exercise Group ◽  
Exercise Session ◽  
Controlled Study ◽  
Control Group ◽  
People Living With Hiv ◽  
Before And After ◽  
Living With Hiv

People living with HIV are at an increased risk of developing cognitive deficits. Physical exercise is an important strategy to improve the brain health of people living with HIV. This randomized, controlled study aimed to investigate the acute effect of a single resistance exercise session on the cognitive function of people living with HIV. Twenty-three people living with HIV were randomized (1:1) to a control group (n = 12) or the exercise group (n = 11). Cognitive function was assessed by the Stroop test and the Trail Making Test. The exercise group was evaluated before and after the exercise session; meanwhile, the control group was evaluated before and after a 40-minute rest period. No statistical difference was found on the effect of exercise on cognitive function ( p > 0.05). This result suggests that one session of resistance exercise was not capable of improving the cognitive function of people with HIV.

scholarly journals Effect of rest interval on cardiovascular responses after resistance exercise

2013 ◽  
Vol 19 (2) ◽  
pp. 252-260 ◽  
Author(s):  
Aluísio Henrique Rodrigues de Andrade Lima ◽  
Cláudia Lúcia de Moraes Forjaz ◽  
Gleyson Queiroz de Moraes Silva ◽  
Ana Paula Andrade Lima ◽  
Ozéas Lima Lins Filho ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Resistance Exercise ◽  
Cardiovascular Response ◽  
Random Order ◽  
Cardiovascular Responses ◽  
Acute Effect ◽  
Interval Length ◽  
Rate Pressure Product ◽  
Rest Interval

OBJECTIVE: To analyze the acute effect of rest interval length on cardiovascular response after resistance exercise. METHODS: Twenty young eutrophic men (23.9 ± 0.7 years;23.8 ± 0.5 kg/m²) performed two experimental sessions in a random order: resistance exercise with a 30-second (I30) and with a 90-second (I90) rest interval between sets. Both sessions included five exercises with 50% of the one-repetition maximum. Before and 24 hours after the experimental sessions, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and rate-pressure product (RPP) were obtained. RESULTS: The SBP, DBP and RPP responses were similar between the I30 and I90 sessions (p>0.05), while the HR after I30 was significantly higher than after I90 (p<0.01) for the first hour after exercise. The cardiovascular responses during the first 24 hours were similar between both sessions (p>0.05). CONCLUSION: Different recovery intervals did not promote post-exercise hypotension, however, a short rest interval increases heart rate for 1 hour after exercise. In addition, within 24 hours of the responses were similar between groups.

Minimal Influence of Carbohydrate Ingestion on the Immune Response Following Acute Resistance Exercise

2001 ◽  
Vol 11 (2) ◽  
pp. 149-161 ◽  
Author(s):  
Alexander J. Koch ◽  
Jeffrey A. Potteiger ◽  
Marcia A. Chan ◽  
Stephen H. Benedict ◽  
Bruce B. Frey
Keyword(s):  
Resistance Exercise ◽  
Plasma Glucose ◽  
High Intensity ◽  
Lymphocyte Proliferation ◽  
Treatment Time ◽  
Exercise Session ◽  
Lymphocyte Response ◽  
Double Blind ◽  
Carbohydrate Ingestion ◽  
Post Exercise

The effect of carbohydrate supplementation (CHO) on the lymphocyte response to acute resistance exercise was examined in 10 resistance-trained males. Subjects completed a randomized double-blind protocol with sessions separated by 14 days. The exercise session consisted of a high intensity, short rest interval squat workout. Subjects consumed 1.0 g · kg body mass−1 CHO or an equal volume of placebo (PLC) 10 min prior to and 10 min following exercise. Blood was collected at rest (REST), immediately post exercise (POST), and at 1.5 hours and 4.0 hours of recovery, and analyzed for plasma glucose, serum cortisol, leukocyte subsets, and phytohemagglutinin (PHA)-stimulated lymphocyte proliferation. A significant Treatment × Time effect was observed for lymphocyte proliferation between CHO and PLC, but post hoc analyses revealed no between-treatment differences at any post-exercise time point. Lymphocyte proliferation was significantly depressed below REST at POST (−39.2% for PLC, −25.7% for CHO). Significant fluctuations in leukocyte subset trafficking were observed for both treatments at POST, 1.5 hours, and 4.0 hours. Plasma glucose was significantly increased POST in CHO compared to PLC. Cortisol was significantly increased from REST to POST in both treatments. These data support a minimal effect of carbohydrate ingestion on the lymphocyte response to high-intensity resistance exercise.

scholarly journals Effects of caffeine ingestion on dynamic visual acuity: a placebo-controlled, double-blind, balanced-crossover study in low caffeine consumers

2021 ◽  
Author(s):  
Beatríz Redondo ◽  
Raimundo Jiménez ◽  
Rubén Molina ◽  
Kristine Dalton ◽  
Jesús Vera
Keyword(s):  
Visual Acuity ◽  
Crossover Study ◽  
Random Order ◽  
Random Motion ◽  
Caffeine Intake ◽  
Moving Targets ◽  
Dynamic Visual Acuity ◽  
Double Blind ◽  
Caffeine Ingestion ◽  
Motion Paths

Abstract Background Acute caffeine ingestion has been associated with improvements in cognitive performance and visual functioning. The main objective of this study was to determine the effects of caffeine intake on dynamic visual acuity (DVA). Methods Twenty-one low caffeine consumers (22.5 ± 1.6 years) took part in this placebo-controlled, double-blind, and balanced crossover study. In two different days and following a random order, participants ingested either caffeine (4 mg/kg) or placebo, and DVA was measured after 60 min of ingesting the corresponding capsule. A recently developed and validated software (moV& test, V&mp Vision Suite, Waterloo, Canada) was used to assess DVA. Results We found a greater accuracy for both the horizontal and random motion paths of DVA after caffeine ingestion (p < 0.001 and p = 0.002, respectively). In regard to the speed of the response, our data revealed that caffeine intake was associated with a faster reaction time for horizontally (p = 0.012) but not for randomly (p = 0.846) moving targets. Also, participants reported higher levels of perceived activation after consuming caffeine in comparison to placebo (p < 0.001). Conclusions Our data suggest that caffeine intake (i.e., a capsule containing 4 mg/kg) has an ergogenic effect on DVA, which may be of special relevance in real-word contexts that require to accurately and rapidly detect moving targets (e.g., sports, driving, or piloting).

Enhancement of High-Intensity Actions and Physical Performance During a Simulated Brazilian Jiu-Jitsu Competition With a Moderate Dose of Caffeine

2016 ◽  
Vol 11 (7) ◽  
pp. 861-867 ◽  
Author(s):  
Francisco Javier Diaz-Lara ◽  
Juan del Coso ◽  
Javier Portillo ◽  
Francisco Areces ◽  
Jose Manuel García ◽  
...  
Keyword(s):  
Blood Lactate ◽  
Physical Performance ◽  
Bench Press ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Random Order ◽  
Moderate Dose ◽  
Double Blind ◽  
Caffeine Ingestion ◽  
Physical Tests

Context:Although caffeine is one of the most commonly used substances in combat sports, information about its ergogenic effects on these disciplines is very limited.Purpose:To determine the effectiveness of ingesting a moderate dose of caffeine to enhance overall performance during a simulated Brazilian jiu-jitsu (BJJ) competition.Methods:Fourteen elite BJJ athletes participated in a double-blind, placebo-controlled experimental design. In a random order, the athletes ingested either 3 mg/kg body mass of caffeine or a placebo (cellulose, 0 mg/kg) and performed 2 simulated BJJ combats (with 20 min rest between them), following official BJJ rules. Specific physical tests such as maximal handgrip dynamometry, maximal height during a countermovement jump, permanence during a maximal static-lift test, peak power in a bench-press exercise, and blood lactate concentration were measured at 3 specific times: before the first combat and immediately after the first and second combats. The combats were video-recorded to analyze fight actions.Results:After the caffeine ingestion, participants spent more time in offensive actions in both combats and revealed higher blood lactate values (P < .05). Performance in all physical tests carried out before the first combat was enhanced with caffeine (P < .05), and some improvements remained after the first combat (eg, maximal static-lift test and bench-press exercise; P < .05). After the second combat, the values in all physical tests were similar between caffeine and placebo.Conclusions:Caffeine might be an effective ergogenic aid for improving intensity and physical performance during successive elite BJJ combats.

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