We are very pleased to have this edition of Albion’s Research Notes written for us by Dr. Lorrie Brilla, Professor, Western Washington University, Center for Fitness Evaluation and Adult Fitness Program, Bellingham, Washington.
The use of creatine as a sport supplement gained widespread popularity in the early 1990s. The Exercise Physiology Laboratory at Western Washington University entered into agreement with Albion Laboratories to conduct the three research studies, one each in 2001, 2006, and 2009 on the Creatine MagnaPower® (magnesium creatine chelate) supplement. The 2001 and 2006 projects were 2 week supplementation regimens and the 2009 project was 4 weeks of supplementation. A series of tests were conducted pre and post of supplementation, at a level of 5 g creatine and 800 mg magnesium per day, with either the chelate or stacked forms; serial tests were conducted every 2nd day in the 2006 project to attempt to identify a breakpoint when creatine effects might be demonstrated. In 2009, the stacked treatment was replaced with alkaline creatine. A placebo group was included in each study for comparison. All subjects completed dietary and physical activity records to substantiate that there were no changes so that any differences would be attributed to the treatments.
Key findings, which may be attributed to the treatments, included the changes presented below.
Body weight: both creatine groups gained weight with only the chelate group reaching statistical significance.
Total body water and intracellular and extracellular water compartments: there were no significant differences between groups (P>0.05).
There were significant differences in %TBW (total body water) for stack condition (P=0.007).
There were significant differences in %ICW (intracellular water) and %ECW (extracellular water) for the chelate condition (P=0.019); Liters of ICW increased, 26.29 L to 28.0 L (P=0.039) and Liters of ECW decreased, 15.75 L to 14.9 L (P=0.009)
The compartmental shifts may correspond to the osmotic effect of intracellular creatine due to supplementation effects. The statistically significant effects in chelate, but not stack, may indicate a greater availability of creatine in the chelate supplemented group.
Anaerobic power as determined by the Wingate test, specifically peak power and mean power in repeat tests: There were no significant differences for group contrasts (P>0.05). However, there were within group differences (P0<.05). Chelate subjects had an increased peak power comparing the 1st test in each pair, pre-post (P<0.05). This change was the only significant difference in peak power for any of the treatment groups.
Anaerobic threshold in a treadmill running test to exhaustion at 90% of maximal capacity as determined from a graded exercise test: There were no significant differences in lactates or Exercise Time to Exhaustion (ETT) at 90% of maximal functional capacity (P>0.05). The ventilatory threshold from oxygen and carbon dioxide measures estimated anaerobic threshold (AT). There was a significant interaction effect (P<0.05). There may be a trend towards reaching AT later in exercise, especially in the magnesiumcreatine groups that may demonstrate a greater contribution from other energy systems before relying on glycolysis.
Peak torque, total work, and power measurements on an isokinetic strength testing device: there were no significant differences between groups (P>0.05). Significant differences were noted within groups for various parameters and in specific sets.