So, just to cover the study in its entirety, here is my brief summary. Strength (measured by 1-RM bench press) increased in the creatine group vs. placebo group and there were no significant differences in body composition.
As for substrate utilization, carbohydrate oxidation was increased during creatine supplementation (as there was a trend for an increase in respiratory exchange ratio (RER); a higher RER means more carbs are being “burned” and lower RER demonstrates greater fat utilization).
The exact mechanism is unclear, so more research is definitely warranted. The authors concluded that these results demonstrate individuals who supplement with creatine may decrease their ability to lose fat due to the RER increase.
Source:
Journal of Applied PhysiologyVolume 93, 2002
M. Erik Huso, Jeffrey S. Hampl, Carol S. Johnston
This is quite understandable IMO. With creatine supplementation you can train at a higher percentage of VO2 max for a longer period of time. And the higher the percentage of the V02 max; the higher your RER (though there is a downward shift caused by endurance training). That’s just one way of looking at it though…
Actually, since the study states that no significant body composition changes were detected this isn’t really a conclusion that can be made.
Perhaps, and I’m just speculating, the extra use of carbohydrates lowers the blood sugar levels and helps reduce insulin levels – thereby balancing out the effect mentioned.
The point is… there probably isn’t a conclusion to be drawn as of yet, though it seems to be something worthy of figuring out.
Well, I’ve read that Don Alessi recommends taking creatine pyruvate while on some of his Meltdown programs and take Creatine w/ Ethyl Ester HCL himself to get ready for shows. I can vouche for the effectiveness of his advice, for what that’s worth.
Does it hinder fat-loss, or does it hinder weight-loss?
I can’t see it affecting fat loss, but I’m no scientist. But creatine does aid in water retention, right? It would follow that the more water you retain, the more weight you will carry.
RER was also higher because they had more Creatine Phosphate available.
The reason you can exercise at a higher VO2 for longer would arguably be because you have a higher PhosphoCreatine capacity. Also, this is only true for the average trainee. Exercise at a higher VO2 has more to do with your Ventilatory and Anaerobic Thresholds then your PhosphoCreatine stores. At the point of near-peak VO2 you might be burning PC for the last minute but you got to that level of desperation from crossing your threshold(s). Also at the point of near-peak VO2 your RER is greater than 1. RER is supposed to only go to 1. This is the point of hyperventilation and greater fatigue (Ventilatory Threshold).
I’d have to vote against the study. You cannot us RER to judge fatloss. Lets consider this. The trainees were set out to lift. Correct me if I am wrong, but heavy lifting is refining your slow glycolitic fibers. Hence if your body is more used to using its slow glycolitic fibers and is neurologically adapted to recruit these fibers more quickly you are going to burn more carbohydrates and phosphocreatine. If you are doing that your RER is going to be higher. Creatine helps in refining these fibers and hence the people who supplement with creatine are going to be better. This means a higher RER.
Also… did they mention what VO2 protocol they used?
To say that creatine hinder fat loss is not politically correct. While it may cause a shift and cause the body to burn carbohydrates instead of fat; this does not neccessarily mean fat loss. This just means the body is either:
Relying on more intramuscular fuel stores (primarily if more type IIx fibers are being activated)
Breaking down less triglycerides into glycerol and FFA’s
Overall; this does not change the first law of thermodynamics; to gain or lose weight (probably the most important concept in fat loss) one must eat less than they burn.
[quote]rainjack wrote:
I can’t see it affecting fat loss, but I’m no scientist. But creatine does aid in water retention, right? It would follow that the more water you retain, the more weight you will carry.
[/quote]
Agreed. I personally have lost plenty of fat while taking creatine. As far as I know, the only weight it affects is the same water weight that it retains. I believe that, since creatine supplies an energy source, it could aid in fat loss since you would not need as many calories to supply energy for your workout. Although the end result could be catabolic.