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Applications of Fenugreek in Sports Nutrition
Published in Dilip Ghosh, Prasad Thakurdesai, Fenugreek, 2022
Colin Wilborn, Aditya Bhaskaran
Creatine, in the form of monohydrate, is one of the most popular supplements for sports nutrition and ergogenic aids. Creatine helps to supply additional substrates for the phosphocreatine system in high-intensity exercise and allows for the energy restoration and maintenance of high-power output for the skeletal muscles (Cooper et al. 2012; Greenhaff et al. 1994). Therefore, creatine is included in the supplementation regimen of many power athletes, including weightlifters and football players. Today, creatine supplementation has evolved to find various ways to maximize absorption rates in the body and in the muscle in an attempt to maximize the ergogenic effect of creatine in sport-specific applications. Higher amounts of creatine in skeletal muscle fulfil high-energy-demanding endeavors during exercise. Therefore, increasing the level of creatine absorption and uptake into the skeletal muscle is an important issue when supplementing creatine. The increased amount of intracellular creatine in skeletal muscle translates into more substantial effects on performance in anaerobic settings.
Mechanotransduction Mechanisms of Hypertrophy and Performance with Resistance Exercise
Published in Peter M. Tiidus, Rebecca E. K. MacPherson, Paul J. LeBlanc, Andrea R. Josse, The Routledge Handbook on Biochemistry of Exercise, 2020
Andrew C. Fry, Justin X. Nicoll, Luke A. Olsen
Creatine is another popular dietary ergogenic aid that is used to improve muscle strength and hypertrophy responses to resistance exercise. Acute supplementations with creatine for 5 days does not improve the anabolic signalling responses to resistance exercise, but did increase gene expression of glucose-transporter 4 (GLUT-4) and MHC-I mRNA (37). In vitro work has shown that creatine enhances MHC-II expression and differentiation in myotubes, an effect that may be mediated by Akt and p38 (38). Since in vitro work suggested creatine may be efficacious in enhancing differentiation, further work sought to investigate the effect of creatine on regeneration of muscle after injury and reported that creatine had no influence on regeneration in muscle injury in rats (32). A limitation of this study was that injury was induced by notexin injection, and muscle damage was not due to contraction-mediated stress.
Dietary Supplement Use in Wrestlers
Published in Charles Paul Lambert, Physiology and Nutrition for Amateur Wrestling, 2020
Creatine is a substance derived from amino acids and is used in the reaction Creatine + ATP <> PCr + ADP. Paul Greenhaff, Roger Harris, Eric Hultman, and their co-authors (Greenhaff et al. 1993; Birch et al. 1994; Casey et al. 1996) were the first ones to research creatine and found that it elevates Phosphocreatine (PCr) in skeletal muscle and improves intermittent high-intensity exercise performance (Greenhaff et al. 1993; Birch et al. 1994; Casey et al. 1996). The typical protocol for supplementing creatine is 20 g/day for 5 days. That is 4 × 5 g/day for 5 days. This loading protocol’s effects last for 1 month. The mechanism of action is elevated PCr stores and possibly an enhanced rate of PCr resynthesis between exercise bouts (Greenhaff et al. 1994).
Effects of Creatine and Caffeine Supplementation During Resistance Training on Body Composition, Strength, Endurance, Rating of Perceived Exertion and Fatigue in Trained Young Adults
Published in Journal of Dietary Supplements, 2022
Avery Pakulak, Darren G. Candow, Julia Totosy de Zepetnek, Scott C. Forbes, Daniele Basta
The lack of effect from creatine supplementation on other measures of muscle thickness may be related to the small sample size, intermittent creatine supplementation protocol and incorporation of males and females. For example, to achieve 80% statistical power, 76 participants were required. Unfortunately, only 28 completed the study which likely decreased our ability to detect small differences between groups over time. This is further highlighted by the greater, yet statistically non-significant, change in whole-body fat free mass from creatine (1.28 kg) compared to the other groups (CR + CAF: 0.29 kg; CAF: −0.03 kg; PLA: 0.78 kg) (Table 3). In addition, participants only consumed creatine on resistance training days. Perhaps daily consumption of creatine is needed to produce significant gains in muscle accretion during short-term training. Finally, there is some evidence to indicate that females may have higher initial intramuscular creatine stores compared to males (Forsberg et al. 1991) which may have decreased their responsiveness to creatine supplementation and influenced our group results.
Dietary supplement use in younger and older men exercising at gyms in Cape Town
Published in South African Journal of Clinical Nutrition, 2021
Marjanne Senekal, Shelly Meltzer, Anri Horne, Nicole CG Abrey, Lauren Papenfus, Stefan van der Merwe, Norman J Temple
There has been much debate regarding the effectiveness of supplementation with protein powders, amino acids and creatine, especially for persons who are aiming to build muscle and strength. There is conclusive evidence that creatine, at least in adults, is safe and effective if used in recommended dosages.33 The evidence is also fairly good for protein powders and amino acids when dietary intake is low and timing is appropriate around training, but is lacking in the case of glutamine.34,35 Younger men were generally inclined to perceive supplements in all three supplement groups to be effective in achieving desired outcomes. This may be linked to the finding that younger men believed that they were knowledgeable regarding supplements. Older men were less convinced that the supplements they took were effective and seemed to feel less knowledgeable on the topic. Of note is that reasons for non-use of supplements included that they do not work and lack of knowledge of supplements.
Selection design phase II trial of high dosages of tamoxifen and creatine in amyotrophic lateral sclerosis
Published in Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 2020
Suma Babu, Eric A. Macklin, Katherine E. Jackson, Elizabeth Simpson, Katy Mahoney, Hong Yu, Jason Walker, Zachary Simmons, William S. David, Paul E. Barkhaus, Laura Simionescu, Mazen M. Dimachkie, Alan Pestronk, Johnny S. Salameh, Michael D. Weiss, Benjamin Rix Brooks, David Schoenfeld, Jeremy Shefner, Swati Aggarwal, Merit E. Cudkowicz, Nazem Atassi
In the current trial, we compared rate of functional decline of high dosage creatine (30 g/day) and two dosages of tamoxifen (40 mg/day, 80 mg/day) in ALS and also explored the safety and tolerability of these compounds. We chose creatine and tamoxifen for our study based on prior promising data in animals and people with ALS. Two prior ALS clinical trials testing long-term creatine at 5 g/day showed large but not significant survival benefits on pooled analysis of 212 participants (HR = 0.35, p = 0.059) (13,14). Higher dosages of creatine were reported to be more effective in Huntington's disease (15), although more recent evidence is negative (16). Given the potential survival benefit of the compound and good tolerance at 5 g/day, we chose to test creatine at a dosage of 30 g/day. Brooks et al. conducted an early phase trial in ALS showing a significant survival benefit in participants randomized to 20, 30, or 40 mg/day dosages of tamoxifen vs. those receiving dosages of 10 mg/week or 10 mg/day (hazard ratio (HR)=2.32, p = 0.040) (17). Given absence of dose-related adverse events (AEs) and a suggestion of a dose-dependent effect on survival (17), we chose to test tamoxifen at 40 mg/day (highest dosage tested previously (17) and 80 mg/day.