Peak Week: Creatine Enhancing the Carb Load!

Peak Week: Creatine Enhancing Carb Loading?

Peak week is just as it sounds, we want to put on the final touches to the physique and “peak” a look for stage. The most impactful variable we can manipulate prior to show day is carbohydrates.

This is without question, increasing carbohydrate intake in a depleted state increases muscle glycogen with in turn produces a fuller bigger muscle.

Now what if we could further enhance this ability to store carbohydrate?

I have seen protocols using creatine monohydrate during the carb loading process to further facilitate a greater glycogen storage amount, which has the potential to give an even larger muscle. But this brings in questions of will this cause water retention and be softer, how much to take, when to take it?

Why Creatine?

Creatine can increase total body water and glycogen content 

Increased muscle creatine concentrations increase skeletal muscle intracellular osmotic pressure, which results in water moving in to the cell. This is partly the more rapid weight gain we see with early creatine loading protocols. Creatine is primarily stored intramuscularly (95%), so an assumption is that most water increase would be inside the muscle cell, but is it?

What about water retention?

We have research that asked this vary question how does fluid distribution change during creatine usage? The researchers had subjects loaded 25g of creatine for 7 days followed by 5g per day for 21 days. (1)

The greatest increase in total body water (1.37L) occurred during the 1 week loading phase.

The researcher directly measure fluid distribution and found a 1.13L increase in Intracellular water in the creatine group, which accounted for 55.4% of total body weight increase, meaning the other fluid increase was extracellular. This matches normal body fluid distribution of 2/3 water inside the cell and 1/3 outside the cell.

Now this is still all inside the compartment of the muscle! This does not mean water is stored around fat cells and skin cells. So if you are peeled out lean, you are going to increase muscle volume without a softer look.

How Does Creatine Change Carbohydrate Metabolism?

 Another research group investigated this question monitoring muscle glycogen change over the creatine loading period. 

After a 5 day creatine loading (20g per day (5g x4)) significantly increased muscle total creatine, free creatine and Creatine phosphate content with a concomitant increase in muscle glycogen storage by 18% (+/-5%). This was while maintain normal eating habits. (2)

The mechanism is via indirect stimulation of muscle glucose uptake and/or glycogen synthesis by increased cellular osmolarity and increase in muscle cell volume. This cell swelling has been identified as an anabolic proliferative signal, stimulating the mitogen-activated protein kinase (MAPK) signaling cascade, which could also be linked to the up-regulation of muscle glycogen synthesis.(3)

What About Creatine’s Impact During Carbohydrate Loading?

There is also a synergy between creatine and glycogen super compensation. Nelson et al performed a 5 day creatine loading protocol prior to a 3 day carb loading protocol, which produced a resulted in a glycogen content ~10% greater than the expected glycogen load. The creating loading was again done using 20g over 3 days. (4) 

We Don’t All Respond Though!

Unfortunately, 20% to 30% of individuals do not respond to Creatine supplementation. This may be due to a few variables such as carbohydrate intake, physical activity, training status, and possibly muscle fiber type.


Creatine loading during a carbohydrate load can further enhance the super-compensation of muscle glycogen causing a larger appearing muscle. This increase in creatine and glycogen increases total body water, but will not impact fluid distribution between intra and extra cellular space. This fluid increase will all primarily be within the muscle and not cause water retention between the skin and muscle.

I would caution that the fuller a muscle gets this can still cause water to be pooled around remaining fat cells and skin, so there is a balance to strike and not to do over due a carb load. I would take a conservative approach as bodybuilders we are not loading carbohydrates to the extent of endurance athletes in studies and must keep in mind the aesthetic view point as well. I recommend add 1-2g (body weight dependent, female vs male) of creatine monohydrate to each carbohydrate containing meal during your carb up period prior to show day.


  1. Powers ME, Arnold BL, Weltman AL, Perrin DH, Mistry D, Kahler DM, Kraemer W, Volek J. Creatine Supplementation Increases Total Body Water Without Altering Fluid Distribution. J Athl Train. 2003 Mar;38(1):44-50. PMID: 12937471; PMCID: PMC155510.
  2. Robinson TM, Sewell DA, Hultman E, Greenhaff PL. Role of submaximal exercise in promoting creatine and glycogen accumulation in human skeletal muscle. J Appl Physiol (1985). 1999 Aug;87(2):598-604. doi: 10.1152/jappl.1999.87.2.598. PMID: 10444618.
  3. van Loon LJ, Murphy R, Oosterlaar AM, Cameron-Smith D, Hargreaves M, Wagenmakers AJ, Snow R. Creatine supplementation increases glycogen storage but not GLUT-4 expression in human skeletal muscle. Clin Sci (Lond). 2004 Jan;106(1):99-106. doi: 10.1042/CS20030116. PMID: 14507259.
  4. Nelson AG, Arnall DA, Kokkonen J, Day R, Evans J. Muscle glycogen supercompensation is enhanced by prior creatine supplementation. Med Sci Sports Exerc. 2001 Jul;33(7):1096-100. doi: 10.1097/00005768-200107000-00005. PMID: 11445755.
  5. Snow RJ, Murphy RM. Factors influencing creatine loading into human skeletal muscle. Exerc Sport Sci Rev. 2003 Jul;31(3):154-8. doi: 10.1097/00003677-200307000-00010. PMID: 12882483.

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