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Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men?
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ORIGINAL ARTICLE
Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? L’hydrochlorure de créatine est-il meilleur que le monohydrate de créatine pour améliorer la performance physique et les adaptations hormonales chez de jeunes hommes? M. Tayebi , H. Arazi ∗ Department of Exercise Physiology, Faculty of Sport Sciences, University of Guilan, Rasht, P.O. Box 1438, Iran Received 12 February 2019; accepted 9 July 2019
KEYWORDS Creatine Hydrochloride; Creatine Monohydrate; Cortisol; Testosterone; Ergogenic
∗
Summary Objectives. — The production and sale of performance-enhancing drugs (PEDs) with annual increase in number and diversity have now become a beneficial industry. At present, there is a kind of creatine supplement, called as creatine hydrochloride (CHCL), which is claimed to have a much higher absorption compared to creatine monohydrate (CRM) supplementation and does not require a loading period. However, this claim has not been fully examined yet. Therefore, the present study aimed to compare the effects of two types of creatine (CHCL and CRM) on physical activity, plasma levels of testosterone (T), and cortisol (Cor) in trained young men. Equipment and methods. — The statistical population of this study included 36 healthy subjects selected by purposive sampling method and with at least six months of resistance training. The subjects were randomly divided into four groups (Group 1: 20 g of CRM, Group 2: 3 g of CRM, Group 3: 3 g of CHCl per day for a week, and Group 4: placebo). The supplements were given to subjects by double-blind manner. Physical performance variables were evaluated on the morning of the first day and before the supplementation, and blood samples (5 cc) were taken in fasting conditions (8—10 hours) to measure the plasma levels of T and Cor. The blood samples were taken again after seven days for physical performance measurements.
Corresponding author. E-mail address: [email protected] (H. Arazi).
https://doi.org/10.1016/j.scispo.2019.07.013 0765-1597/© 2019 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: Tayebi M, Arazi H. Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? Sci sports (2019), https://doi.org/10.1016/j.scispo.2019.07.013
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M. Tayebi, H. Arazi Results. — The results showed that there were no significant differences between the effects of 3 and 20 g of CRM and 3 g of CHCL on the vigor, power, plasma levels of T and Cor, and T/C ratio. In other words, 3 g of CHCL did not result in improved performance and hormonal changes compared to 20 g of CRM. Conclusion. — According to the results, the multi-day period of supplementation with CHCL in comparison to CRM cannot have much effect on performance and improve the hormonal status of individuals in the short term. © 2019 Elsevier Masson SAS. All rights reserved.
MOTS CLÉS Chlorhydrate de créatine ; Monohydrate de créatine ; Cortisol ; Testostérone ; Substance ergogénique
Résumé Objectif. — La production et la vente de compléments alimentaires sont une industrie en plein essor. Actuellement, une nouvelle présentation de créatine complémentaire a été développée, et est présentée comme ayant une meilleure absorption digestive que la créatine monohydrate (MRC) et ne nécessitant pas une période de charge. Ce supplément est appelé chlorhydrate de créatine (CHCL). Cette propriété alléguée n’a pas été complètement étudiée. Par conséquent, la présente étude visait à comparer les effets de deux types de Créatine (CHCL et CRM) sur l’activité physique, et les taux plasmatiques de testostérone (T) et de cortisol (Cor) chez de jeunes hommes. Méthode de recherche. — Trente-six sportifs en bonne santé ont participé à cette recherche avec un entraînement de résistance de six mois au moins. Les sujets ont été répartis au hasard en 4 groupes: (groupe 1: 20 gr de CRM, groupe 2: 3 gr de CRM, groupe 3: 3 gr CHCL par jour pendant une semaine et le groupe IV: placebo (PL)). Des suppléments ont été administrés aux sujets en double aveugle. Le matin du premier jour, avant l’administration des compléments aux sujets, les variables de la performance physique ont été évaluées et puis des échantillons de sang de 5 ml ont été prélevés de chaque sujet à jeun (8 à 10 heures) pour mesurer les taux plasmatiques de T et de Cor. Après 7 jours, les échantillons de sang ont été prélevés à nouveau et la performance physique a été mesurée. Résultats. — Les résultats obtenus ont montré qu’il n’y avait pas de différence significative entre les effets de 3 et 20 gr de CRM et de 3 gr de CHCL sur la performance, les taux plasmatiques de T et Cor et le rapport T/C. En d’autres termes, 3 gr de CHCL n’ont pas abouti à l’amélioration de la performance et aux changements hormonaux par rapport à 20 gr de CRM. Conclusion. — D’après les résultats obtenus, on peut conclure qu’une période de quelques jours de supplémentation en CHCL comparée au CRM ne permet pas d’affecter la performance et l’amélioration du concentrations de T et de Cor à court terme. © 2019 Elsevier Masson SAS. Tous droits r´ eserv´ es.
1. Introduction Although dietary supplements are consumed throughout the community, their use is more common among athletes. Creatine is one of these supplements [1], which is present in the human body, especially in muscle, and is an organic acid. In addition to being supplied through exogenous sources, the body also has the ability to produce creatine [2]. The popularity of creatine supplementation has increased dramatically among athletes in recent years [3]. The performance-enhancing effect of creatine has probably increased its usage in athletes. According to estimates, 80% of athletes consumed creatine before or during the 1998 Winter Olympics. The amount of creatine sales was about $100 million in 1998 and reached about $400 million in 2006. It should be noted that 7.2 million kg of creatine supplement was consumed in the whole world in 1998 [4]. In newer statistics, creatine-rich foods account for a large amount of annual sales of food supplements in the United States alone, which is about $7.2 billion [3].
Creatine is found in large quantities of food. Hence, the use of this substance is not prohibited by any sports organization. In addition, most sports organizations declare the ban on the use of certain food supplements to their own athletes [5—7]. For this reason, athletes can purchase and consume creatine without concern of punishment or violation of the prohibition of restricted substances [3]. It has been reported that the prevalence of creatine use among athletes and military personnel in surveying studies was generally about 15—40% [8,9], and that it was most commonly used among men who were power athletes. There are reports on the prevalence of creatine use among high-school athletes [10—12]. The National Collegiate Athletic Association (NCAA) in the United States and Canada (2014) reported that creatine is one of the most popular dietary supplements consumed by athletic men, while rates of use have been reported to be only 2.0%—8.3% for female athletes in various sports [13]. The production and sale of performance-enhancing drugs (PEDs) with increasing annual number and diversity have
Please cite this article in press as: Tayebi M, Arazi H. Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? Sci sports (2019), https://doi.org/10.1016/j.scispo.2019.07.013
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Effects of Creatine hydrochloride on hormonal changes now become a beneficial industry [14]. Meanwhile, creatine supplement is no exception, and new forms of creatine are produced every year. As mentioned previously, the explosive growth in sales can be one of the reasons for introducing various types of creatine, the effectiveness status of which is unclear yet [3]. One of the most common and widely used forms in the last few decades is the CRM supplement used by athletes in power struggles and those in need of muscle mass. The effectiveness of this supplement is subject to 5—7-day loading times, and athletes must necessarily consume significant amounts of this substance to affect their performance. Currently, there is a kind of creatine supplement, called creatine hydrochloride (CHCL), which is claimed to have a much higher absorption compared to creatine monohydrate (CRM) supplementation and does not require loading time. According to the manufacturers, this substance can have more absorption than the classical ones and has more effect on the performance of the athlete’s body. Here, the key question with regard to this new creatine supplement is whether or not supplementation with CHCL at a dose of 3 g compared with CRM at doses of 20 g and 3 g over a 7-day period will have a more effective impact on the physiological performance and plasma levels of testosterone (T) and cortisol (Cor) hormones in trained young men. According to our studies, very limited research has been carried out on CHCL and supplementation protocols in this regard, so that the manufacturers’ claims have not been approved or rejected so far. This issue has confused athletes taking this new product. Therefore, the present study aimed to investigate the effect of CHCL in comparison to CRM on physical performance and plasma levels of T and Cor in trained young men.
3 Table 1
Characteristics of participants (n = 36).
Variable
Mean ± SD
Age (yr) Height (cm) Weight (kg) Body fat (%) BMI (kg.m−2 ) Energy intake (kilocalories) Protein consumption (%) Carbohydrates consumption (%) Fat consumption (%)
22.16 ± 2.09 177.91 ± 7.20 70.47 ± 10.66 12.95 ± 1.54 22.30 ± 3.49 2761.42 ± 103.67 15.57 ± 2.50 56.85 ± 2.26 27.57 ± 3.50
BMI: Body mass index; SD: standard deviation.
(8 - 10 hours) to measure plasma levels of T (Monobind kit, USA, coefficient of variation of 4.8%) and Cor (Monobind kit, USA, coefficient of variation of 6.4%). The samples were transferred to the laboratory and kept at −70 ◦ C until the measurement of hormonal variables. During the analysis, the blood samples were centrifuged (3000 rpm) at room temperature. After 7 days (i.e., on the morning of the eighth day), the posttest was taken from the subjects the same as the pretest. In addition, subjects were asked to maintain their usual diet and avoid intense physical activity 48 hours before the tests. This study was approved by the Ethics Committee of the University.
2.2. Statistical analysis
2. Materials and methods
Shapiro—Wilk test was used to determine the normality of the data, which were then analyzed by repeated measures two-way ANOVA and Bonferroni post hoc test using SPSS version 16 software at a significance level of P ≤ 0.05.
2.1. Subjects and measurements
3. Results
In the present quasi-experimental research, the subjects were selected purposively among the students in sport science at the University of Guilan (Iran). Inclusion criteria were the absence of musculoskeletal damage, cardiovascular disease, lack of supplementation and medication, and a history of at least six months of resistance training. The participants completed informed consent forms and were examined for medical records. Finally, 36 subjects with mean values of body fat (12.95 ± 1.54%), weight (70.10 ± 47.66 kg), height (177.91 ± 7.20 cm), and age (22.16 ± 2.09 years) were randomly divided into four groups (Group 1: 20 g of CRM, Group 2: 3 g of CRM, Group 3: 3 g of CHCl (purely mixed with water) per day for a week, and Group 4: placebo (PL)). The supplements were given to subjects by double-blind manner. On the morning of the first day and before giving supplements to the subjects, initial measurements, including weight, height, BMI, fat percentage, and pre-test variables were physical performance measurements of explosive power (Sargent jump), upperbody strength (bench press), lower-body strength (squat), peak power, minimum power, mean power, and fatigue index (Wingate test). Blood samples (5 cc) were taken from the brachial vein of each subject in fasting conditions
Table 1 presents the descriptive characteristics of the subjects. The results showed that explosive power, upper body strength, and lower-body strength had significant differences in the posttest of the group receiving 20 g of CRM compared to its pretest (P ≤ 0.05), while this difference was not significant in the groups receiving 3 g of CRM and CHCL (Fig. 1). In addition, no significant differences were found between the groups receiving 3 g of CHCL and those with 3 and 20 g of CRM. The group receiving 20 g of CRM showed significant changes in Cor, T, and T/C ratio (P ≤ 0.05), while these changes were not significant in comparison with the groups receiving 3 g of CRM and 3 g of CHCL (Fig. 2). No significant differences were found between the group receiving 3 g of CHCL and those supplemented with 3 and 20 g of CRM (P ≥ 0.05). Finally, the results from power showed that peak power, minimum power, and mean power were significantly different in the posttest of group receiving 20 g of CRM compared to its pretest (P ≤ 0.05), while the difference in the fatigue index was not significant (Table 2). Comparing the groups receiving 3 g of CHCL with groups receiving 3 and 20 g of CRM revealed no significant differences (P ≥ 0.05) (Table 2).
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Figure 1 Changes in explosive power (A), upper body strength (B) and lower body strength (C). *: Significant difference compared to pre-test (P ≤ 0.05). CRM: creatine monohydrate; CHCL: creatine hydrochloride; PL: placebo.
Figure 2 Changes in Cortisol (A), Testosterone (B) and Testosterone to cortisol ratio (C). *: Significant difference compared to pre-test (P ≤ 0.05). CRM: creatine monohydrate; CHCL: creatine hydrochloride; PL: placebo.
4. Discussion The results of this study showed that the effect of CRM with a dose of 3 g was not significant on the plasma Cor and T levels, which is in line with those of most previous studies. In some studies, no significant changes were observed in Cor and T levels with 20 g of CRM supplementation [15,16], which
contradicts the results of this study. Although the number, age, exercise, supplementation, and circadian rhythm of the hormones can influence hormonal secretion levels, one of the contradictory reasons can be the nature of the research. The present study merely examines the supplementation effects, and the lack of control on the subjects’ exercises is one of the research limitations. In most studies,
Please cite this article in press as: Tayebi M, Arazi H. Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? Sci sports (2019), https://doi.org/10.1016/j.scispo.2019.07.013
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Effects of Creatine hydrochloride on hormonal changes Table 2
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The statistical results of subject’s power (mean ± SD).
Peak power (W) Minimum power (W) Mean power (W) Fatigue index (%)
Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test
3 g CRM
3 g CHCL
20 g CRM
PL
638.88 ± 185.75 654.61 ± 138.18 268.12 ± 96.23 301.80 ± 66.71 501.67 ± 130.17 531.34 ± 91.17 55.80 ± 19.33 52.16 ± 15.73
647.96 ± 99.90 694.25 ± 125.39 288.37 ± 104.41 291.94 ± 16.91 517.96 ± 81.62 545.66 ± 68.05 54.61 ± 16.19 56.59 ± 8.66
632.84 ± 79.45 780.35 ± 75.23a 285.88 ± 92.63 363.18 ± 97.82a 508.51 ± 49.26 633.85 ± 77.52a 53.34 ± 18.95 53.61 ± 7.14
700.85 ± 112.06 747.17 ± 93.65 308.49 ± 130.00 335.80 ± 108.05 527.41 ± 96.56 603.87 ± 100.88 55.43 ± 18.73 55.34 ± 12.17
CRM: Creatine Monohydrate, CHCL: Creatine Hydrochloride, PL: Placebo. a Significant difference compared to pre-test (P ≤ 0.05).
supplementation was associated with exercise capable of affecting the secretion levels of these hormones, and this is a reason for the contradiction of the present study with other studies. In a study by Dobgensky et al. (2014), Cor hormone showed a significant decrease after taking 20 g of CRM and maltodextrin following swimming compared to the PL group, as was also found herein [17]. The insignificant hormone results in the current study can be attributed to the lack of CHCL loading, the period of usage, and the dose used, since these can affect the results of the research and challenge the claims of the manufacturers of this supplement. According to manufacturers, CHCL supplements used in the present study were expected to have stronger effects than CRM supplements due to its high absorption properties and greater solubility in water. Even so, using 3 g of CHCL had no impacts on the secretion of Cor and T hormones. The results of this study are considered to be the beginning of a new research in this area because two previous studies (Elisa et al., 2015; Jefferson et al., 2017) focused on the effects of this supplement on body composition and exercise performance [18,19]. Therefore, researchers in the future are recommended to investigate the effects of different doses of this supplement on hormonal secretion in different conditions. The calculation of T and Cor makes it possible to compute their ratio [20]. In general, a high T/C ratio indicates an anabolic state and a low T/C ratio represents a catabolic state [21]. In the present study, a significant increase was observed in T/C ratio only with the use of CRM supplementation at a dose of 20 g; this dose, therefore, exhibits the anabolic effects. Many studies have examined and documented the effect of creatine supplementation on the power [22—25]. In the present study, the power increased with 20 g of CRM. It should be considered that researches also indicate that the creatine has no effect on the power in different conditions [26]. In this study, the power did not change significantly with 3 g of CRM and 3 g of CHCL. As noted, evidence suggests that creatine supplementation leads to increasing individual abilities for intense exercise and performance enhancement as maximal exercise in each session, and accelerating intermittent recovery periods. This increase also occurs at the initial level of phosphocreatine (PCr), muscle glycogen, and rapid and
re-synthesis of PCr. With this method, creatine supplementation acts as an ergogenic and provides high-intensity exercises with more exercise to athletes [27]. Arsioru et al. examined the use of two doses of creatine with 20 g for 5 days and 10 g for 23 days without exercise and concluded that the upper-body strength by running bench press movement increased by 8% for the creatine group and 18% for creatine group with resistance training. In the leg press movement the power increased 16% and 24% in the creatine the supplement groups, respectively, along with resistance training [22]. Akerson et al., on the other hand, observed no significant improvements in performance and CHCL with 30 days of creatine supplementation [26], which is inconsistent with the claims of the manufacturers of this supplement. This form of supplement may possibly be effective with higher doses or consumption over a longer period and with loading periods. The basics of performance enhancement are such that creatine supplementation increases the storage of muscle creatine, resulting in the production of intramuscular PCr and adenosine triphosphate. Naturally, this process will eventually lead to prolonged vigorous physical activity and improved athletic performance [23,28]. An athlete using creatine helps to synthesize PCr, but this did not happen for CHCL levels in the present study [22,29]. According to previous reports, creatine has a buffering effect on muscle acidity. On the other hand, one of the main reasons for discontinuing exercise is the increased generation of lactic acid produced following the glycolysis. The benefits of increasing the mentioned buffer capacity with creatine usage is that it provides a substrate to the muscle with increased buffer capacity, which can fulfill its work before getting pH-dependent fatigue, although the accumulation of lactic acid is higher [30]. As noted above, there were significant differences in explosive power, upper body strength, and lower-body strength by taking 20 g of CRM in this study, but these differences were not significant with 3 g of CRM and 3 g of CHCL. This lack of difference is likely to be due to the CRM supplementary dosage and possibly the lack of significant differences between the effects of CRM and CHCL. These differences were also observed in the anaerobic power of the participants. Since power and strength are related together, it was expected to have similar results with the power and strength [31].
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Despite reports and claims, the inter-group comparison presented evidence of high adsorption and permeability with a 41-fold water solubility of CHCL in comparison with CRM. This suggests that the greater permeability of CHCL than CRM [27] might lessen the amount needed for this type of creatine to fill muscle creatine reserves. Accordingly, the producers of this type of creatine claim that CHCL, similar to CRM, does not require a loading period [30]. Our intergroup comparison showed no significant differences in levels of Cor, T, T/C ratio, power, and strength between 3 g and 20 g of CRM creatine and 3 g of CHCL creatine, hence, this kind of creatine probably requires a loading period and should be introduced in a longer period to demonstrate its impact.
5. Conclusion The CHCL supplementation seems to have no positive effects on the physical performance and hormonal status in trained young men without a loading period of one week. Further research is required to draw a definite conclusion.
Funding Nil.
Disclosure of interest The authors declare that they have no competing interest.
Acknowledgements The authors would like to thank the participants who took part in this study.
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[8] Fraczek B, Warzecha M, Tyrala F, Pieta A. Prevalence of the use of effective ergogenic aids among professional athletes. nstwowego Zakładu Higieny 2016;67(3). Roczniki Pa´ [9] Huang SH, Johnson K, Pipe AL. The use of dietary supplements and medications by Canadian athletes at the Atlanta and Sydney Olympic Games. Clin J Sport Med 2006;16(1): 27—33. [10] Scofield DE, Unruh S. Dietary supplement use among adolescent athletes in central Nebraska and their sources of information. J Strength Cond Res 2006;20(2):452—5. [11] McGuine TA, Sullivan JC, Bernhardt DT. Creatine supplementation in high school football players. Clin J Sport Med 2001;11(4):247—53. [12] LaBotz M, Smith BW. Creatine supplement use in an NCAA Division I athletic program. Clin J Sport Med 1999;9(3):167—9. [13] Youngstedt SD, O’connor PJ, Dishman RK. The effects of acute exercise on sleep: a quantitative synthesis. Sleep 1997;20(3):203—14. [14] Garazhian YA, Arazi HA, Dadban MI, Sayvand ZA, et al. The Effect of Short-term Supplementation of Creatine Monohydrate on Performance, Power and Muscle Work. Sports Physiol J 2012;3(12):47—58. [15] Eijnde BO, Hespel P. Short-term creatine supplementation does not alter the hormonal response to resistance training. Med Sci Sports Exerc 2001;33(3):449—53. [16] Vatani DS, Faraji H, Soori R, Mogharnasi M. The effects of creatine supplementation on performance and hormonal response in amateur swimmers. Sci Sports 2011;26(5):272—7. [17] Dobgenski V, Santos MG, Campbell B, Kreider R. Shortterm creatine supplementation suppress the cortisol response to a high-intensity swim-sprint workout. J Nutr Health Sci 2014;1(2):204. [18] de Franc ¸a E, Avelar B, Yoshioka C, Santana JO, Madureira D, Rocha LY, et al. Creatine HCl and Creatine Monohydrate Improve Strength but Only Creatine HCl Induced Changes on Body Composition in Recreational Weightlifters. Food Nutr Sci 2015;6(17):1624. [19] Santana JO, de Franc ¸a E, Madureira D, da Silva BR, Caperuto EC. Combined effect of creatine monohydrate or creatine hydrochloride and caffeine supplementation in runners’ performance and body composition. Revista Brasileira de Prescric ¸ão e Fisiologia do Exercício (RBPFEX) 2017;11(70):844—54. [20] Halson SL, Jeukendrup AE. Does overtraining exist? Sports Med 2004;34(14):967—81. [21] Donald MC, Moore CI, McIntyre J, Carmody A, Donne KB. Acute effects of 24-h sleep deprivation on salivary cortisol and testosterone concentrations and testosterone to cortisol ratio following supplementation with caffeine or placebo. Int J Exerc Sci 2017;10(1):108. [22] Arciero PJ, Hannibal NS, Nindl BC, Gentile CL, Hamed J, Vukovich MD. Comparison of creatine ingestion and resistance training on energy expenditure and limb blood flow. Metab Clin Exp 2001;50(12):1429—34. [23] Rawson ES, Volek JS. Effects of creatine supplementation and resistance training on muscle strength and weightlifting performance. J Strength Cond Res 2003;17(4):822—31. [24] Willoughby DS, Rosene J. Effects of oral creatine and resistance training on myosin heavy chain expression. Med Sci Sports Exerc 2001;33(10):1674—81. [25] Candow DG, Chilibeck PD. Timing of creatine or protein supplementation and resistance training in the elderly. Appl Physiol Nutr Metab 2007;33(1):184—90. [26] Eckerson JM, Bull AA, Moore GA. Effect of thirty days of creatine supplementation with phosphate salts on anaerobic working capacity and body weight in men. The Journal of Strength & Conditioning Research 2008;22(3):826—32. [27] Parise G, Mihic S, MacLennan D, Yarasheski KE, Tarnopolsky MA. Effects of acute creatine monohydrate supplementation
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ORIGINAL ARTICLE
Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? L’hydrochlorure de créatine est-il meilleur que le monohydrate de créatine pour améliorer la performance physique et les adaptations hormonales chez de jeunes hommes? M. Tayebi , H. Arazi ∗ Department of Exercise Physiology, Faculty of Sport Sciences, University of Guilan, Rasht, P.O. Box 1438, Iran Received 12 February 2019; accepted 9 July 2019
KEYWORDS Creatine Hydrochloride; Creatine Monohydrate; Cortisol; Testosterone; Ergogenic
∗
Summary Objectives. — The production and sale of performance-enhancing drugs (PEDs) with annual increase in number and diversity have now become a beneficial industry. At present, there is a kind of creatine supplement, called as creatine hydrochloride (CHCL), which is claimed to have a much higher absorption compared to creatine monohydrate (CRM) supplementation and does not require a loading period. However, this claim has not been fully examined yet. Therefore, the present study aimed to compare the effects of two types of creatine (CHCL and CRM) on physical activity, plasma levels of testosterone (T), and cortisol (Cor) in trained young men. Equipment and methods. — The statistical population of this study included 36 healthy subjects selected by purposive sampling method and with at least six months of resistance training. The subjects were randomly divided into four groups (Group 1: 20 g of CRM, Group 2: 3 g of CRM, Group 3: 3 g of CHCl per day for a week, and Group 4: placebo). The supplements were given to subjects by double-blind manner. Physical performance variables were evaluated on the morning of the first day and before the supplementation, and blood samples (5 cc) were taken in fasting conditions (8—10 hours) to measure the plasma levels of T and Cor. The blood samples were taken again after seven days for physical performance measurements.
Corresponding author. E-mail address: [email protected] (H. Arazi).
https://doi.org/10.1016/j.scispo.2019.07.013 0765-1597/© 2019 Elsevier Masson SAS. All rights reserved.
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M. Tayebi, H. Arazi Results. — The results showed that there were no significant differences between the effects of 3 and 20 g of CRM and 3 g of CHCL on the vigor, power, plasma levels of T and Cor, and T/C ratio. In other words, 3 g of CHCL did not result in improved performance and hormonal changes compared to 20 g of CRM. Conclusion. — According to the results, the multi-day period of supplementation with CHCL in comparison to CRM cannot have much effect on performance and improve the hormonal status of individuals in the short term. © 2019 Elsevier Masson SAS. All rights reserved.
MOTS CLÉS Chlorhydrate de créatine ; Monohydrate de créatine ; Cortisol ; Testostérone ; Substance ergogénique
Résumé Objectif. — La production et la vente de compléments alimentaires sont une industrie en plein essor. Actuellement, une nouvelle présentation de créatine complémentaire a été développée, et est présentée comme ayant une meilleure absorption digestive que la créatine monohydrate (MRC) et ne nécessitant pas une période de charge. Ce supplément est appelé chlorhydrate de créatine (CHCL). Cette propriété alléguée n’a pas été complètement étudiée. Par conséquent, la présente étude visait à comparer les effets de deux types de Créatine (CHCL et CRM) sur l’activité physique, et les taux plasmatiques de testostérone (T) et de cortisol (Cor) chez de jeunes hommes. Méthode de recherche. — Trente-six sportifs en bonne santé ont participé à cette recherche avec un entraînement de résistance de six mois au moins. Les sujets ont été répartis au hasard en 4 groupes: (groupe 1: 20 gr de CRM, groupe 2: 3 gr de CRM, groupe 3: 3 gr CHCL par jour pendant une semaine et le groupe IV: placebo (PL)). Des suppléments ont été administrés aux sujets en double aveugle. Le matin du premier jour, avant l’administration des compléments aux sujets, les variables de la performance physique ont été évaluées et puis des échantillons de sang de 5 ml ont été prélevés de chaque sujet à jeun (8 à 10 heures) pour mesurer les taux plasmatiques de T et de Cor. Après 7 jours, les échantillons de sang ont été prélevés à nouveau et la performance physique a été mesurée. Résultats. — Les résultats obtenus ont montré qu’il n’y avait pas de différence significative entre les effets de 3 et 20 gr de CRM et de 3 gr de CHCL sur la performance, les taux plasmatiques de T et Cor et le rapport T/C. En d’autres termes, 3 gr de CHCL n’ont pas abouti à l’amélioration de la performance et aux changements hormonaux par rapport à 20 gr de CRM. Conclusion. — D’après les résultats obtenus, on peut conclure qu’une période de quelques jours de supplémentation en CHCL comparée au CRM ne permet pas d’affecter la performance et l’amélioration du concentrations de T et de Cor à court terme. © 2019 Elsevier Masson SAS. Tous droits r´ eserv´ es.
1. Introduction Although dietary supplements are consumed throughout the community, their use is more common among athletes. Creatine is one of these supplements [1], which is present in the human body, especially in muscle, and is an organic acid. In addition to being supplied through exogenous sources, the body also has the ability to produce creatine [2]. The popularity of creatine supplementation has increased dramatically among athletes in recent years [3]. The performance-enhancing effect of creatine has probably increased its usage in athletes. According to estimates, 80% of athletes consumed creatine before or during the 1998 Winter Olympics. The amount of creatine sales was about $100 million in 1998 and reached about $400 million in 2006. It should be noted that 7.2 million kg of creatine supplement was consumed in the whole world in 1998 [4]. In newer statistics, creatine-rich foods account for a large amount of annual sales of food supplements in the United States alone, which is about $7.2 billion [3].
Creatine is found in large quantities of food. Hence, the use of this substance is not prohibited by any sports organization. In addition, most sports organizations declare the ban on the use of certain food supplements to their own athletes [5—7]. For this reason, athletes can purchase and consume creatine without concern of punishment or violation of the prohibition of restricted substances [3]. It has been reported that the prevalence of creatine use among athletes and military personnel in surveying studies was generally about 15—40% [8,9], and that it was most commonly used among men who were power athletes. There are reports on the prevalence of creatine use among high-school athletes [10—12]. The National Collegiate Athletic Association (NCAA) in the United States and Canada (2014) reported that creatine is one of the most popular dietary supplements consumed by athletic men, while rates of use have been reported to be only 2.0%—8.3% for female athletes in various sports [13]. The production and sale of performance-enhancing drugs (PEDs) with increasing annual number and diversity have
Please cite this article in press as: Tayebi M, Arazi H. Is creatine hydrochloride better than creatine monohydrate for the improvement of physical performance and hormonal changes in young trained men? Sci sports (2019), https://doi.org/10.1016/j.scispo.2019.07.013
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Effects of Creatine hydrochloride on hormonal changes now become a beneficial industry [14]. Meanwhile, creatine supplement is no exception, and new forms of creatine are produced every year. As mentioned previously, the explosive growth in sales can be one of the reasons for introducing various types of creatine, the effectiveness status of which is unclear yet [3]. One of the most common and widely used forms in the last few decades is the CRM supplement used by athletes in power struggles and those in need of muscle mass. The effectiveness of this supplement is subject to 5—7-day loading times, and athletes must necessarily consume significant amounts of this substance to affect their performance. Currently, there is a kind of creatine supplement, called creatine hydrochloride (CHCL), which is claimed to have a much higher absorption compared to creatine monohydrate (CRM) supplementation and does not require loading time. According to the manufacturers, this substance can have more absorption than the classical ones and has more effect on the performance of the athlete’s body. Here, the key question with regard to this new creatine supplement is whether or not supplementation with CHCL at a dose of 3 g compared with CRM at doses of 20 g and 3 g over a 7-day period will have a more effective impact on the physiological performance and plasma levels of testosterone (T) and cortisol (Cor) hormones in trained young men. According to our studies, very limited research has been carried out on CHCL and supplementation protocols in this regard, so that the manufacturers’ claims have not been approved or rejected so far. This issue has confused athletes taking this new product. Therefore, the present study aimed to investigate the effect of CHCL in comparison to CRM on physical performance and plasma levels of T and Cor in trained young men.
3 Table 1
Characteristics of participants (n = 36).
Variable
Mean ± SD
Age (yr) Height (cm) Weight (kg) Body fat (%) BMI (kg.m−2 ) Energy intake (kilocalories) Protein consumption (%) Carbohydrates consumption (%) Fat consumption (%)
22.16 ± 2.09 177.91 ± 7.20 70.47 ± 10.66 12.95 ± 1.54 22.30 ± 3.49 2761.42 ± 103.67 15.57 ± 2.50 56.85 ± 2.26 27.57 ± 3.50
BMI: Body mass index; SD: standard deviation.
(8 - 10 hours) to measure plasma levels of T (Monobind kit, USA, coefficient of variation of 4.8%) and Cor (Monobind kit, USA, coefficient of variation of 6.4%). The samples were transferred to the laboratory and kept at −70 ◦ C until the measurement of hormonal variables. During the analysis, the blood samples were centrifuged (3000 rpm) at room temperature. After 7 days (i.e., on the morning of the eighth day), the posttest was taken from the subjects the same as the pretest. In addition, subjects were asked to maintain their usual diet and avoid intense physical activity 48 hours before the tests. This study was approved by the Ethics Committee of the University.
2.2. Statistical analysis
2. Materials and methods
Shapiro—Wilk test was used to determine the normality of the data, which were then analyzed by repeated measures two-way ANOVA and Bonferroni post hoc test using SPSS version 16 software at a significance level of P ≤ 0.05.
2.1. Subjects and measurements
3. Results
In the present quasi-experimental research, the subjects were selected purposively among the students in sport science at the University of Guilan (Iran). Inclusion criteria were the absence of musculoskeletal damage, cardiovascular disease, lack of supplementation and medication, and a history of at least six months of resistance training. The participants completed informed consent forms and were examined for medical records. Finally, 36 subjects with mean values of body fat (12.95 ± 1.54%), weight (70.10 ± 47.66 kg), height (177.91 ± 7.20 cm), and age (22.16 ± 2.09 years) were randomly divided into four groups (Group 1: 20 g of CRM, Group 2: 3 g of CRM, Group 3: 3 g of CHCl (purely mixed with water) per day for a week, and Group 4: placebo (PL)). The supplements were given to subjects by double-blind manner. On the morning of the first day and before giving supplements to the subjects, initial measurements, including weight, height, BMI, fat percentage, and pre-test variables were physical performance measurements of explosive power (Sargent jump), upperbody strength (bench press), lower-body strength (squat), peak power, minimum power, mean power, and fatigue index (Wingate test). Blood samples (5 cc) were taken from the brachial vein of each subject in fasting conditions
Table 1 presents the descriptive characteristics of the subjects. The results showed that explosive power, upper body strength, and lower-body strength had significant differences in the posttest of the group receiving 20 g of CRM compared to its pretest (P ≤ 0.05), while this difference was not significant in the groups receiving 3 g of CRM and CHCL (Fig. 1). In addition, no significant differences were found between the groups receiving 3 g of CHCL and those with 3 and 20 g of CRM. The group receiving 20 g of CRM showed significant changes in Cor, T, and T/C ratio (P ≤ 0.05), while these changes were not significant in comparison with the groups receiving 3 g of CRM and 3 g of CHCL (Fig. 2). No significant differences were found between the group receiving 3 g of CHCL and those supplemented with 3 and 20 g of CRM (P ≥ 0.05). Finally, the results from power showed that peak power, minimum power, and mean power were significantly different in the posttest of group receiving 20 g of CRM compared to its pretest (P ≤ 0.05), while the difference in the fatigue index was not significant (Table 2). Comparing the groups receiving 3 g of CHCL with groups receiving 3 and 20 g of CRM revealed no significant differences (P ≥ 0.05) (Table 2).
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Figure 1 Changes in explosive power (A), upper body strength (B) and lower body strength (C). *: Significant difference compared to pre-test (P ≤ 0.05). CRM: creatine monohydrate; CHCL: creatine hydrochloride; PL: placebo.
Figure 2 Changes in Cortisol (A), Testosterone (B) and Testosterone to cortisol ratio (C). *: Significant difference compared to pre-test (P ≤ 0.05). CRM: creatine monohydrate; CHCL: creatine hydrochloride; PL: placebo.
4. Discussion The results of this study showed that the effect of CRM with a dose of 3 g was not significant on the plasma Cor and T levels, which is in line with those of most previous studies. In some studies, no significant changes were observed in Cor and T levels with 20 g of CRM supplementation [15,16], which
contradicts the results of this study. Although the number, age, exercise, supplementation, and circadian rhythm of the hormones can influence hormonal secretion levels, one of the contradictory reasons can be the nature of the research. The present study merely examines the supplementation effects, and the lack of control on the subjects’ exercises is one of the research limitations. In most studies,
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Effects of Creatine hydrochloride on hormonal changes Table 2
5
The statistical results of subject’s power (mean ± SD).
Peak power (W) Minimum power (W) Mean power (W) Fatigue index (%)
Pre-test Post-test Pre-test Post-test Pre-test Post-test Pre-test Post-test
3 g CRM
3 g CHCL
20 g CRM
PL
638.88 ± 185.75 654.61 ± 138.18 268.12 ± 96.23 301.80 ± 66.71 501.67 ± 130.17 531.34 ± 91.17 55.80 ± 19.33 52.16 ± 15.73
647.96 ± 99.90 694.25 ± 125.39 288.37 ± 104.41 291.94 ± 16.91 517.96 ± 81.62 545.66 ± 68.05 54.61 ± 16.19 56.59 ± 8.66
632.84 ± 79.45 780.35 ± 75.23a 285.88 ± 92.63 363.18 ± 97.82a 508.51 ± 49.26 633.85 ± 77.52a 53.34 ± 18.95 53.61 ± 7.14
700.85 ± 112.06 747.17 ± 93.65 308.49 ± 130.00 335.80 ± 108.05 527.41 ± 96.56 603.87 ± 100.88 55.43 ± 18.73 55.34 ± 12.17
CRM: Creatine Monohydrate, CHCL: Creatine Hydrochloride, PL: Placebo. a Significant difference compared to pre-test (P ≤ 0.05).
supplementation was associated with exercise capable of affecting the secretion levels of these hormones, and this is a reason for the contradiction of the present study with other studies. In a study by Dobgensky et al. (2014), Cor hormone showed a significant decrease after taking 20 g of CRM and maltodextrin following swimming compared to the PL group, as was also found herein [17]. The insignificant hormone results in the current study can be attributed to the lack of CHCL loading, the period of usage, and the dose used, since these can affect the results of the research and challenge the claims of the manufacturers of this supplement. According to manufacturers, CHCL supplements used in the present study were expected to have stronger effects than CRM supplements due to its high absorption properties and greater solubility in water. Even so, using 3 g of CHCL had no impacts on the secretion of Cor and T hormones. The results of this study are considered to be the beginning of a new research in this area because two previous studies (Elisa et al., 2015; Jefferson et al., 2017) focused on the effects of this supplement on body composition and exercise performance [18,19]. Therefore, researchers in the future are recommended to investigate the effects of different doses of this supplement on hormonal secretion in different conditions. The calculation of T and Cor makes it possible to compute their ratio [20]. In general, a high T/C ratio indicates an anabolic state and a low T/C ratio represents a catabolic state [21]. In the present study, a significant increase was observed in T/C ratio only with the use of CRM supplementation at a dose of 20 g; this dose, therefore, exhibits the anabolic effects. Many studies have examined and documented the effect of creatine supplementation on the power [22—25]. In the present study, the power increased with 20 g of CRM. It should be considered that researches also indicate that the creatine has no effect on the power in different conditions [26]. In this study, the power did not change significantly with 3 g of CRM and 3 g of CHCL. As noted, evidence suggests that creatine supplementation leads to increasing individual abilities for intense exercise and performance enhancement as maximal exercise in each session, and accelerating intermittent recovery periods. This increase also occurs at the initial level of phosphocreatine (PCr), muscle glycogen, and rapid and
re-synthesis of PCr. With this method, creatine supplementation acts as an ergogenic and provides high-intensity exercises with more exercise to athletes [27]. Arsioru et al. examined the use of two doses of creatine with 20 g for 5 days and 10 g for 23 days without exercise and concluded that the upper-body strength by running bench press movement increased by 8% for the creatine group and 18% for creatine group with resistance training. In the leg press movement the power increased 16% and 24% in the creatine the supplement groups, respectively, along with resistance training [22]. Akerson et al., on the other hand, observed no significant improvements in performance and CHCL with 30 days of creatine supplementation [26], which is inconsistent with the claims of the manufacturers of this supplement. This form of supplement may possibly be effective with higher doses or consumption over a longer period and with loading periods. The basics of performance enhancement are such that creatine supplementation increases the storage of muscle creatine, resulting in the production of intramuscular PCr and adenosine triphosphate. Naturally, this process will eventually lead to prolonged vigorous physical activity and improved athletic performance [23,28]. An athlete using creatine helps to synthesize PCr, but this did not happen for CHCL levels in the present study [22,29]. According to previous reports, creatine has a buffering effect on muscle acidity. On the other hand, one of the main reasons for discontinuing exercise is the increased generation of lactic acid produced following the glycolysis. The benefits of increasing the mentioned buffer capacity with creatine usage is that it provides a substrate to the muscle with increased buffer capacity, which can fulfill its work before getting pH-dependent fatigue, although the accumulation of lactic acid is higher [30]. As noted above, there were significant differences in explosive power, upper body strength, and lower-body strength by taking 20 g of CRM in this study, but these differences were not significant with 3 g of CRM and 3 g of CHCL. This lack of difference is likely to be due to the CRM supplementary dosage and possibly the lack of significant differences between the effects of CRM and CHCL. These differences were also observed in the anaerobic power of the participants. Since power and strength are related together, it was expected to have similar results with the power and strength [31].
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Despite reports and claims, the inter-group comparison presented evidence of high adsorption and permeability with a 41-fold water solubility of CHCL in comparison with CRM. This suggests that the greater permeability of CHCL than CRM [27] might lessen the amount needed for this type of creatine to fill muscle creatine reserves. Accordingly, the producers of this type of creatine claim that CHCL, similar to CRM, does not require a loading period [30]. Our intergroup comparison showed no significant differences in levels of Cor, T, T/C ratio, power, and strength between 3 g and 20 g of CRM creatine and 3 g of CHCL creatine, hence, this kind of creatine probably requires a loading period and should be introduced in a longer period to demonstrate its impact.
5. Conclusion The CHCL supplementation seems to have no positive effects on the physical performance and hormonal status in trained young men without a loading period of one week. Further research is required to draw a definite conclusion.
Funding Nil.
Disclosure of interest The authors declare that they have no competing interest.
Acknowledgements The authors would like to thank the participants who took part in this study.
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