I’m sure most of us have taken or have been taking creatine for a while. My question is: How long can creatine be taken before I need to lay off of it for a while. And if I do need to lay off of it, is it better to do it during a bulking cycle or a cutting cycle? Is it beneficial to take creatine when doing a Mag 10, 2 on 2 off cycle?

There was a report on T-mag a while back that covered one of the nutritional conferences I believe and I remember one of the presentations reported on mentioned the researcher had been using creatine for I believe 6 years with no problems and said he believed it a safe supp with best results when used consistently all the time with no need to cycle.

I look at creatine as a fuel much in the way I view carbohydrates rather than a magical supplement. There are periods where creatine supplementation helps fuel effective training. For most of us, we are striving for effective training all the time, so there is often no reason to cycle off creatine. There are also times where I think creatine supplementation is absolutely vital. These would be during high volume, high intensity hypertrophy training, much like the training during a MAG-10 cylce and on the other hand during low carbohydrate diets while using high intensity, low volume training.

I find that when I am on creatine for too long (6-8 weeks) it seems like I lose the advantage that it offers and I hit a definite plateau. I have gained the best results by following Charles Poliquin’s recommendations and cycling off every three weeks. I go three weeks on and then three weeks off. I can still feel the creatine working for at least a couple of weeks after I go off and then when I go back on I feel the “creatine pump” again like the first time I took it and I believe it helps me with strength gains in the long run. Additionally I have come across some rat data that suggests that the creatine transporter is down regulated after chronic creatine supplementation.

Mol Cell Biochem 1998 Jul;184(1-2):427-37 Creatine supplementation in health and disease. Effects of chronic creatine ingestion in vivo: down-regulation of the expression of creatine transporter isoforms in skeletal muscle.

Guerrero-Ontiveros ML, Wallimann T.

Institute for Cell Biology, Swiss Federal Institute of Technology, ETH-Honggerberg, Zurich.

Interest in creatine (Cr) as a nutritional supplement and ergogenic aid for athletes has surged over recent years. After cellular uptake, Cr is phosphorylated to phosphocreatine (PCr) by the creatine kinase (CK) reaction using ATP. At subcellular sites with high energy requirements, e.g. at the myofibrillar apparatus during muscle contraction, CK catalyzes the transphosphorylation of PCr to ADP to regenerate ATP, thus preventing a depletion of ATP levels. PCr is thus available as an immediate energy source, serving not only as an energy buffer but also as an energy transport vehicle. Ingestion of creatine increases intramuscular Cr, as well as PCr concentrations, and leads to exercise enhancement, especially in sprint performance. Additional benefits of Cr supplementation have also been noticed for high-intensity long-endurance tasks, e.g. shortening of recovery periods after physical exercise. The present article summarizes recent findings on the influence of Cr supplementation on energy metabolism, and introduces the Cr transporter protein (CreaT), responsible for uptake of Cr into cells, as one of the key-players for the multi-faceted regulation of cellular Cr homeostasis. Furthermore, it is suggested that patients with disturbances in Cr metabolism or with different neuro-muscular diseases may benefit from Cr supplementation as an adjuvant therapy to relieve or delay the onset of symptoms. Although it is still unclear how Cr biosynthesis and transport are regulated in health and disease, so far there are no reports of harmful side effects of Cr loading in humans. However, in this study, we report that chronic Cr supplementation in rats down-regulates in vivo the expression of the CreaT. In addition, we describe the presence of CreaT isoforms most likely generated by alternative splicing.

PMID: 9746337 [PubMed - indexed for MEDLINE]

If the same effect happens in humans this could explain why I lose the "pump" after being on creatine for a while.