Boire plus n'augmente pas l'efficacité de la créatine
THE INFLUENCE OF HYDRATION STATUS ON CHANGES IN BODY MASS DURING CREATINE SUPPLEMENTATION
E. SOBOLEWSKI Journal of Strength and Conditioning Research 2016 VOLUME 30 | SUPPLEMENT 1 | FEBRUARY | S43
It is commonly reported and speculated that Creatine (Cr)
supplementation causes increases in body mass. Creatine’s
osmotic properties are believed to increase intracellular water
(ICW), resulting in greater water retention and subsequent increases
in body mass.
Purpose: The purpose of this study
was to examine the influence of hydration status on the
changes in body mass and fluid distribution during Cr supplementation.
Methods: Fifty subjects (age = 20 6 2 years),
where assigned to a Cr (n = 25) or a placebo group (n =
25). Participants supplemented 4 times daily for 5 days with
5 g Cr monohydrate +20 g dextrose (Cr) or 20 g dextrose (PL).
Testing was conducted prior to supplementation and during
the loading phase on days 2, 4, and 6. Bioelectrical Impedance
Spectroscopy was used to determine total body water (TBW),
extracellular water (ECW) and ICW. Hydration status was
determined through urine specific gravity as determined by
a refractometer at baseline prior to supplementation. A mixed
factorial ANOVA and ANCOVA controlling for hydration
status was used to examine body mass, TBW, ECW, and
ICW. Follow up bonferonni corrected comparisons were used
when appropriate.
Results: For body mass alone there was no
interaction effect (F = 0.88, p = 0.08), no main effect for group
(F = 4.80, p = 0.91), but a mass did increase over the 6 days
for both groups (F = 7.34, p , 0.01). When accounting for
hydration status there was an interaction effect for body mass
(F = 3.06, p = 0.03). The placebo group weighed more at
baseline but after 3 full days (day 4) of supplementation, both
groups were similar in body mass for the remainder of the
loading period as a result of the ;0.6 kg (p # 0.05) increase
in body mass for the Cr group. There was no interaction or
main effects for TBW, ECW or ICW (p . 0.05), however when
controlling for hydration status there was only a significant difference
between groups for ECW (F = 4.38, p = 0.04) with the
PL group being higher than the Cr group at all-time points.
Conclusions: The results of this study indicate that hydration
status may play a role in the mass gain associated with Cr
supplementation with those being less hydrated not experiencing
the same amount of mass changes as those who are
hydrated. If the osmotic conditions outside the cell are high
in solutes then an increase in cellular Cr levels may not pull
water into the cell thus not cause an increase in water content
as seen with this study.
Practical Applications: It has been suggested to coaches and players to drink more water with
Cr supplementation but this study found that the increase in
mass seen with Cr use maybe due to increased water/fluid
supplementation rather than Cr alone.
It is recommended that Cr users maintain healthy hydration levels and not “over” consume
water as excess water leads to mass gain not Cr.
