Creatine is one of the most researched and scientifically supported supplements on the market. Creatine is naturally synthesized in the body in the liver and kidney at about 1 g/d a day. Around 95% of creatine is stored in muscles and current protocols for creatine consumption involve a loading phase where an individual consumes between 5-20 grams of creatine causing saturation of intracellular creatine stores (Ribeiro et al., 2021). Creatine works in the body by resynthesizing ATP in skeletal muscles through the enzyme creatine phosphokinase. Creatine phosphokinase catalyzes the reaction by transferring an inorganic phosphate from phosphorylcreatine to ADP forming ATP. ATP resynthesis through phosphocreatine increases available energy during exercise and prolongs skeletal muscle work capacity and reduces fatigue during exercise (Ribeiro et al., 2021).
A new study published in June of 2022 looked at the psychological effect of creatine consumption pre-workout to see if it induced improvement in resistance training. They used four groups in the study, one control that did not receive any treatment, one group that received dextrose and were informed that they received dextrose, another group that received dextrose but were told they had received creatine monohydrate, and the last group received creatine and were told they had received creatine. The groups were assessed on exercise performance and rate of perceived exertion (RPE). All treatment groups, not the control, increased the number of repetitions performed on bench press and smith-machine squats. Additionally, all treatment groups reported lower RPE/repetitions ratio meaning their perceived exertion was lower for reach repetition performed in bench press and squat. There were no significant differences between the group who received creatine and the group who believed they had received creatine in the study (Aguiar et al., 2022). With acute supplementation of creatine, just believing that the creatine will aid in exercise performance can contribute to increased performance.
Ribeiro F, Longobardi I, Perim P, Duarte B, Ferreira P, Gualano B, Roschel H, Saunders B. Timing of Creatine Supplementation around Exercise: A Real Concern? Nutrients. 2021 Aug 19;13(8):2844. doi: 10.3390/nu13082844. PMID: 34445003; PMCID: PMC8401986.
Aguiar MS, Pereira R, Koch AJ, Machado M. Psychological effect of acute creatine pre-workout supplementation induces performance improvement in resistance exercise. Res Sports Med. 2022 Jun 21:1-12. doi: 10.1080/15438627.2022.2090253. Epub ahead of print. PMID: 35726856.
Collin, I find this to be a very interesting study. Physiology aside, I would argue you could replicate this study using pre-workout as a condition as well. I bet pre-workout would have a similar affect on the RPE/repetitions ratio as the treatment groups. I know pre-workout has a load of ingredients effecting physiology, but I think the cognitive aspect surrounding what you expect it to do could affect your perceived ability independent of actually taking it. That is, if you believe you were given pre-workout then you'd report a lower ratio. I also liked how you mention the 'loading phase' with respect to creatine. I understand that when you start taking creatine you're supposed to start with this loading phase. What someone should research before taking creatine (me) is the phase system so as to maximize creatine's effect or minimize my financial loss.
ReplyDeleteOn the physiological side of creatine in skeletal muscles, stores are used up in about 10 seconds of high intensity workouts. A study I was reading measured an increase of creatine stores of about 10-40% over short-term usage. I would be interested to know if that was about the estimated increase in your study's experimental setup. In support of your observations, even if creatine supplementation could increase stores, the appreciable increase in energy would likely amount to seconds worth and who even knows if it can aid in actively replacing creatine used during the middle of a workout.
ReplyDeletehttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5753968/#:~:text=Skeletal%20muscle%20cells%20store%20enough,by%2010%25%20to%2040%25.
DeleteI have also used creatine in the past and noticed a difference in the gym as well as my physique, but this study enforces some suspicions I had myself about creatine and its effects. I never believed that creatine was a harmful supplement that would ruin your kidneys. Although it does increase the amount of work your kidneys have to do, this is usually a small tradeoff for the benefits of physical exercise and bodybuilding. One thing I noticed about the study is that there wasn't a group that was secretly given creatine and told it was dextrose. This seems to be the only combination missing from the experimental groups, but I doubt it would have had a big effect on the results considering there were no significant differences between the experimental groups with/without creatine. It's true that the placebo effect has a very big impact on our mentality and attitude. This topic definitely reminded me of the important effects that mind-muscle connection can have, especially for weight-lifting. We've spoken about how the recruitment of motor units by the nervous system is just as, if not more, important than the actual amount of muscle tissue available. This nervous/mental connection to our muscle is once again emphasized by your study. Just being in a positive mentality and attitude of being able to lift more will help increase muscle output. Check out this study as well that talks about increasing muscle exertion and isolation through mentally focusing on that specific muscle.
ReplyDeleteCalatayud, J., Vinstrup, J., Jakobsen, M.D. et al. Importance of mind-muscle connection during progressive resistance training. Eur J Appl Physiol 116, 527–533 (2016). https://doi.org/10.1007/s00421-015-3305-7
This is an interesting read Collin, I am a little surprised that they did the creatine pre-workout. When I was in my prime lifting days, I was always told to take it post-workout to get a greater outcome on improving body composition. I personally would just mix it in with my protein shake. According to this study, it is important to take pre and post work out supplements, but their findings showed that there was an improvement with taking creatine post-workout over the pre.(Antonio & Ciccone, 2013) It also explains a study where creatine was given immediately after a workout or two hours post-workout. They found the immediate consumption of creatine proved to increase fiber area mean in their quadriceps femoris muscles whereas no increase was observed in the two-hour delayed consumption group. This loading phase is news to me, and I will need to look further into it.
ReplyDeleteAntonio, J., & Ciccone, V. (2013). The effects of pre versus post workout supplementation of creatine monohydrate on body composition and strength. Journal of the International Society of Sports Nutrition, 10(1), 36. https://doi.org/10.1186/1550-2783-10-36