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Michael J. Duncan, Mark Lyons and Joanne Hankey

Purpose:

This study examined the placebo effect of caffeine on number of repetitions (reps), rating of perceived exertion (RPE), blood pressure (BP), and peak heart rate (PHR) during resistance-training exercise with repetitions (reps) performed to volitional failure.

Methods:

Following determination of 1-rep maximum in single-leg leg extension, 15 males performed reps to failure at 60% 1-RM in 3 conditions: control, perceived caffeine condition, and perceived placebo condition presented in a randomized order. Participants were informed they would ingest 250 mL of solution that contained either 3 mg·kg−1 caffeine or 3 mg·kg−1 placebo 1 h before each exercise trial. A deceptive protocol was employed and subjects consumed a placebo solution in both conditions. During each condition, total reps, RPE for the active muscle and overall body, and PHR were recorded.

Results:

Subjects completed 2 more reps when they perceived they had ingested caffeine. RPE was significantly (P = .04) lower in the perceived caffeine and control conditions and RPE for the active muscle was significantly higher across all conditions compared with RPE for the overall body. No substantial differences were evident in PHR across conditions.

Conclusions:

Results of this study are similar to studies of actual caffeine ingestion. However, the perception of consuming a substance that purportedly enhances performance is sufficient enough to enable individuals to complete a greater number of reps to failure during short-term resistance exercise.

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Darren G. Candow, Philip D. Chilibeck, Karen E. Chad, Murray J. Chrusch, K. Shawn Davison and Darren G. Burke

The authors previously found that creatine (Cr) combined with 12 weeks of resistance training enhanced muscle strength and endurance and lean tissue mass (LTM) in older men. Their purpose in this study was to assess these variables with cessation of Cr combined with 12 weeks of reduced training (33% lower volume) in a subgroup of these men (n = 8, 73 years old) compared with 5 men (69 years old) who did not receive Cr. Strength (1-repetition maximum [1-RM]), endurance (maximum number of repetitions over 3 sets at 70–80% 1-RM), and LTM (dual-energy X-ray absorptiometry) were assessed before and after 12 weeks of Cr cessation combined with reduced-volume training. No changes in strength or LTM occurred. Muscle endurance was significantly reduced (7–21%; p < .05), with the rate of change similar between groups. Withdrawal from Cr had no effect on the rate of strength, endurance, and loss of lean tissue mass with 12 weeks of reduced-volume training.

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Samuel T. Howe, Phillip M. Bellinger, Matthew W. Driller, Cecilia M. Shing and James W. Fell

Beta-alanine may benefit short-duration, high-intensity exercise performance. The aim of this randomized double-blind placebo-controlled study was to examine the effects of beta-alanine supplementation on aspects of muscular performance in highly trained cyclists. Sixteen highly trained cyclists (mean ± SD; age = 24 ± 7 yr; mass = 70 ± 7kg; VO2max = 67 ± 4ml·kg−1·min–1) supplemented with either beta-alanine (n = 8, 65 mg·kg−1BM) or a placebo (n = 8; dextrose monohydrate) over 4 weeks. Pre- and postsupplementation cyclists performed a 4-minute maximal cycling test to measure average power and 30 reciprocal maximal isokinetic knee contractions at a fixed angular velocity of 180°·sec−1 to measure average power/repetition, total work done (TWD), and fatigue index (%). Blood pH, lactate (La) and bicarbonate (HCO3 -) concentrations were measured preand postisokinetic testing at baseline and following the supplementation period. Beta-alanine supplementation was 44% likely to increase average power output during the 4-minute cycling time trial when compared with the placebo, although this was not statistically significant (p = .25). Isokinetic average power/repetition was significantly increased post beta-alanine supplementation compared with placebo (beta-alanine: 6.8 ± 9.9W, placebo: –4.3 ± 9.5 W, p = .04, 85% likely benefit), while fatigue index was significantly reduced (p = .03, 95% likely benefit). TWD was 89% likely to be improved following beta-alanine supplementation; however, this was not statistically significant (p = .09). There were no significant differences in blood pH, lactate, and HCO3 between groups (p > .05). Four weeks of beta-alanine supplementation resulted in worthwhile changes in time-trial performance and short-duration muscular force production in highly trained cyclists.

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Daniel G. Syrotuik, Kirsten L. MacFadyen, Vicki J. Harber and Gordon J. Bell

To examine the effects of elk velvet antler supplementation (EVA) combined with training on resting and exercise-stimulated hormonal response, male (n = 25) and female (n = 21) rowers ingested either E VA (560 mg/d) or placebo (PL) during 10 wk of training. VO2max, 2000 m rowing time, leg and bench press strength were determined before and after 5 and 10 wk of training. Serum hormone levels were measured prior to and 5 and 60 min after a simulated 2000 m rowing race. VO2max and strength increased and 2000 m times decreased similarly (P < 0.05) with training. There was no significant difference between the EVA and PL group for any hormonal response. Testosterone (males only) and growth hormone (both genders) were higher 5 min after the simulated race (P < 0.05) but returned to baseline at 60 min. Cortisol was higher 5 and 60 min compared to rest (both genders) (P < 0.05) and was higher 60 min post-exercise following 5 and 10 wk of training. It appears that 10 wk of EVA supplementation does not significantly improve rowing performance nor alter hormonal responses at rest or after acute exercise than training alone.

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Craig Pickering and Jozo Grgic

Caffeine is a well-established ergogenic aid, with performance-enhancing effects confirmed at the meta-analysis level ( Grgic et al., 2019 ) across a variety of exercise types, including aerobic and muscular endurance, muscle strength, anaerobic power, speed, and jumping performance ( Grgic et

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Ozcan Esen, Ceri Nicholas, Mike Morris and Stephen J. Bailey

confer ergogenic potential during running and cycling exercise in recreationally active participants, it has been suggested that an ergogenic effect of NO 3 − supplementation in these exercise modalities is less likely in well-trained individuals. 2 , 3 However, there is evidence that NO 3

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Jozo Grgic, Filip Sabol, Sandro Venier, Ivan Mikulic, Nenad Bratkovic, Brad J. Schoenfeld, Craig Pickering, David J. Bishop, Zeljko Pedisic and Pavle Mikulic

The use of caffeine is highly prevalent among both the general population and athletes. 1 , 2 The International Olympic Committee has also identified caffeine as having strong scientific support for its ergogenic effects on exercise performance. 3 There is good evidence that caffeine ingestion

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Peter J. Whalley, Chey G. Dearing and Carl D. Paton

Caffeine (1,3,7-trimethylxanthine) is the most widely consumed of all psychoactive drugs and is frequently used by athletes as a performance-enhancing ergogenic aid. A number of previous reviews have comprehensively documented the performance-enhancing effects of caffeine for both aerobic- 1 , 2

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Christian P. Cheung, Joshua T. Slysz and Jamie F. Burr

transport chain proteins in preconditioned myocardial tissue, possibly resulting in a more favorable mitochondrial energy state. 6 These effects may similarly persist in skeletal muscle and therefore act as an ergogenic aid through improved metabolic efficiency. There is further evidence that IPC may

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Neil D. Clarke, Darren L. Richardson, James Thie and Richard Taylor

ergogenic effect on exercise performance. 2 Despite this, Astorino and Roberson 3 concluded that the mechanism by which caffeine provides an ergogenic effect in high-intensity exercise is likely to be multifactorial, with central factors such as adenosine antagonism being the most probable mechanism, but