Efekti različitih formulacija kreatina na motoričko-funkcionalne sposobnosti, biohemijske markere i energetiku mišića i mozga rekreativnih sportista

Abstract

Uvod: Kreatin predstavlja intenzivno istraživano, efikasno ergogeno sredstvo koje dovodi do povećanja ćelijskih rezervi kreatina. Poslednjih decenija suplementacija guanidinosirćetnom kiselinom (GAA) predstavljena je kao superiorno sredstvo za unapređenje ćelijske bioenergetike u odnosu na kreatin i alternativno rešenje kojim bi se uspešno otklonili eventualni nedostaci suplementacije kreatinom. Cilj ovog istraživanja jeste utvrđivanje efekata kombinovanog unosa kreatina i GAA na antropometrijski status, apsolutnu (maksimalnu), eksplozivnu i repetitivnu snagu, kardiorespiratornu izdržljivost, kao i biohemijske i indikatore tkivno-ćelijske bioenergetike kod zdravih muškaraca koji se rekreativno bave sportom. Materijali i metode: U istraživanju je učestvovalo 14 muškaraca starosti između 18 i 30 godina (telesna visina 176,49±7,25 cm; telesna masa 79,86±13,86 kg), koji se bace sportom 5 i više sati nedeljno i poseduju višegodišnje trenažno iskustvo u različitim tipovima aktivnosti. Studija je organizovana kao randomizirana, dvostruko slepa, cross-over studija kontrolisana kreatinom. Eksperimentalna grupa unosila je kombinaciju kreatina i GAA (3 g Cr + 1 g GAA) tokom 4 nedelje, dok je kontrolna grupa konzumirala ekvimolarnu količinu kreatina (4 g Cr). Nakon završetka tretmana i wash out perioda (4 nedelje), grupe su zamenile tretmane. Dnevna doza suplementacije podrazumevala je unos praha rastvorenog u 250 ml mlake vode nakon noćnog gladovanja, pre doručka. Inicijalno, te nakon završetka svake faze, sprovedena su antropometrijska merenja, biohemijske analize, testovi motoričko-funkcionalnih sposobnosti i magnetna spektroskopija četvoroglavog mišića natkolenice i sive i bele moždane mase. Rezultati: Tretman kreatinom doveo je do statistički značajnog povećanja telesne mase u odnosu na inicijalno merenje (79,86±13,86 kg vs 81,48±13,22 kg; p=0,01), dok ove razlike nisu utvrđene nakon tretmana Cr+GAA (80,6±13,68 kg; p>0,05). Značajno povećanje vrednosti Cr u serumu uočeno je u obe grupe (inicijalno 20,87±5,3 μM/L vs Cr 44,45±16,53 μM/L; p=0.001, i Cr+GAA 39,83±12,37 μM/L; p=0,001), pri čemu nisu uočene značajne razlike između tretmana (p>0,05). Povećanje vrednosti Crn u serumu nakon tretmana nije statistički potvrđeno (p>0,05). Vrednosti Crn bile su niže pre unosa suplementacije u odnosu na Cr+GAA grupu (84±89 μM/L vs 88,45±6,44 μM/L), dok je unos kreatina doveo do dodatnog povećanja (90,51±12,56 μM/L). Vrednosti GAA i tHcy u serumu nisu se značajno razlikovale nakon oba nutritivna tretmana uodnosu na inicijalno merenje (p>0,05). Unos suplementacije doveo je do statistički značajnog povećanja vrednosti snage. U testu potisak sa ravne klupe sa slobodnim tegovima (BP) vrednosti su porasle nakon unosa kreatina (97,08±23,67 kg vs 101,67±22,7 kg; p=0,003), te dodatno nakon kombinacije Cr+GAA (102,92±25,71 kg; p=0,004). U testu prednji čučanj statistički značajno povećanje vrednosti snage utvrđeno je nakon oba tretmana (inicijalno 107,5±15,3 kg vs Cr 122,5±10,55 kg; p<0,00 i Cr+GAA 121,25±8,29 kg; p<0,001), dok razlike između grupa nisu statistički potvrđene (p>0,05). U testu skok iz stojećeg stava sa zamahom rukama (VJ) uočeno je statistički značajno smanjenje visine skoka nakon tretmana kreatinom (57,06±6,02 cm vs 53,88±5,17 cm; p>0,001) i tretmana Cr+GAA (54,86±4,88 cm; p=0,006) u odnosu na inicijalno merenje. Kombinacija Cr i GAA dovela je do statistički značajnog porasta kreatina u interesnoj regiji sive moždane mase (Z=-2,02; p=0,043), ali ne i tretman kreatinom zasebno (p>0,05). Tretman Cr+GAA doveo je do povećanja vrednosti kreatina za dodatnih 4,0% u odnosu na kreatin (inicijalno 8,94±0,77 mM vs Cr 9,09±0,93 mM; Cr+GAA 9,45±0,7 mM). Povećanje vrednosti kreatina u interesnoj regiji bele moždane mase nakon unosa suplementacije nije statistički potvrđeno (p>0,05), ipak unos kreatina doveo je do povećanja od 7,0% u odnosu na inicijalno merenje (7,60±0,63 mM vs 8,22±0,52 mM), a tretman Cr+GAA je ostvario dodatno poećanje od 6,3% u odnosu na tretman kreatinom (8,74±1,13 mM). Kombinacija Cr i GAA ostvarila je dodatno povećanje vrednosti Cr u četvoroglavom mišiću natkolenice od 13,1% u odnosu na unos kreatina zasebno (inicijalno 35,53±5,86 mM vs Cr 36,03±4,91 mM; Cr+GAA 40,74±3,45 mM). Zaključak: Kombinacija kreatina i GAA u odnosu 3:1 potvrdila se kao superioran tretman za unapređenje ćelijskih rezervi kreatina u mišićnom i moždanom tkivu u odnosu na kreatin. Nova formulacija kreatina dovela je do značajnog povećanja snage gornjih i donjih ekstremiteta, praćenog značajno manjim povećanjem telesne mase u odnosu na kreatin, nakon 4-nedeljnog tretmana kod zdravih, fizički aktivnih muškaraca. Istraživani tretman značajno je umanjio rizik od hiperhomocisteinemije u odnosu na unos GAA zasebno.

Introduction: Creatine is a well-recognized, effective ergogenic agent that leads to an increase in cellular creatine reserves. In recent years, guanidinoacetic acid (GAA) supplementation has been presented as a superior treatment for tackling cellular bioenergetic compared to creatine, and an alternative solution that could eliminate potential shortcomings of creatine. The aim of this study is to determine the effects of combined intake of creatine and GAA on anthropometric status, maximal, explosive and repetitive strength, aerobic endurance, as well as biochemical and indicators of tissue bioenergetics in healthy, well-trained men. Methods: 14 men between ages 18 and 30 (height 176.49±7.25 cm; body mass 79.86±13.86 kg) engaged in different physical activities for 5 or more hours per week participated in this research. In this randomized, double-blind, creatine-controlled cross-over study, the experimental group ingested a combination of creatine and GAA (3 g Cr + 1g GAA) for 4 weeks. The control group consumed an equimolar dose of creatine (4 g Cr) per day. Upon the end of the first phase and wash-out period (4 weeks), the groups switched treatments to ensure between-subjects comparison. The daily dose included the intake of the powder dissolved in 250 ml of lukewarm water immediately after night fasting. Anthropometric measurements, biochemical analyses, functional ability tests, and magnetic spectroscopy of muscle and brain tissue were conducted initially, as well as after the completion of each research phase. Results: Creatine treatment led to a statistically significant increase in body weight compared to the initial measurement (79,86±13,86 kg vs 81,48±13,22 kg; p=0,01), while these differences were not determined after Cr+GAA treatment (80,6±13,68 kg; p>0,05). A significant increase in Cr serum levels was observed in both groups (initial 20,87±5,3 μM/L vs Cr 44,45±16,53 μM/L; p=0.001, and Cr+GAA 39,83±12,37 μM/L; p=0,001), and no significant differences were observed between treatments (p>0,05). The increase in Crn serum levels was not statistically confirmed after treatments (p>0,05). Crn values were lower before supplementation compared to the Cr+GAA group (84±89 μM/L vs 88,45±6,44 μM/L), while creatine intake led to an additional increase (90,51±12,56 μM/L). Additionally, GAA and tHcy serum values did not differ significantly after both nutritional treatments compared to the initial measurement (p>0,05). Supplementation led to a statistically significant increase in strength. In the bench press, the values increased after creatineintake (97,08±23,67 kg vs 101,67±22,7 kg; p=0,003), and additionally after the Cr+GAA combination (102,92±25,71 kg; p=0,004). In the front squat, a statistically significant increase in strength was observed after both treatments (initial 107,5±15,3 kg vs Cr 122,5±10,55 kg; p<0,00 and Cr+GAA 121,25±8,29 kg; p<0,001), while the differences between treatments were not statistically confirmed (p>0,05). In the vertical jump, a statistically significant decrease in jump height was observed after creatine treatment (57,06±6,02 cm vs 53,88±5,17 cm; p>0,001), and Cr+GAA treatment (54,86±4,88 cm; p=0,006) compared to initial values. Furthermore, the combination of Cr and GAA led to a statistically significant increase in gray matter creatine levels (Z=-2,02; p=0,043), but not creatine treatment alone (p>0,05) compared to initial values. Cr+GAA led to an increase in creatine levels by an additional 4,0% compared to creatine (initial 8,94±0,77 mM vs Cr 9,09±0,93 mM; Cr+GAA 9,45±0,7 mM). The increase in white matter creatine levels was not statistically confirmed after the supplementation intake (p>0,05), however, the creatine intake led to an increase of 7,0% compared to the initial measurement (7,60±0,63 mM vs 8,22±0,52 mM), and the Cr+GAA treatment led to an additional increase of 6,3% compared to creatine alone (8,74±1,13 mM). The Cr+GAA combination achieved an additional 13,1% increase in creatine levels in m. vastus medialis compared to creatine intake alone (initial 35,53±5,86 mM vs Cr 36,03±4,91 mM; Cr+GAA 40,74±3,45 mM). Conclusion: The combination of creatine and GAA in a 3:1 ratio proved to be a superior treatment for improving the cellular creatine reserves in muscle and brain tissue compared to creatine alone. A new creatine formulation produced significant increases in upper and lower body strength, accompanied by significantly less weight gain compared to creatine after 4-weeks treatment in healthy, physically active men. The investigated treatment significantly reduced the risk of hyperhomocysteinemia compared to GAA intake alone.