Creatine monohydrate supplementation does not increase muscle strength, lean body mass, or muscle phosphocreatine in patients with myotonic dystrophy type 1

Muscle Nerve. 2004 Jan;29(1):51-8. doi: 10.1002/mus.10527.


Creatine monohydrate (CrM) supplementation may increase strength in some types of muscular dystrophy. A recent study in myotonic muscular dystrophy type 1 (DM1) did not find a significant treatment effect, but measurements of muscle phosphocreatine (PCr) were not performed. We completed a randomized, double-blind, cross-over trial using 34 genetically confirmed adult DM1 patients without significant cognitive impairment. Participants received CrM (5 g, approximately 0.074 g/kg daily) and a placebo for each 4-month phase with a 6-week wash-out. Spirometry, manual muscle testing, quantitative isometric strength testing of handgrip, foot dorsiflexion, and knee extension, handgrip and foot dorsiflexion endurance, functional tasks, activity of daily living scales, body composition (total, bone, and fat-free mass), serum creatine kinase activity, serum creatinine concentration and clearance, and liver function tests were completed before and after each intervention, and muscle PCr/beta-adenosine triphosphate (ATP) ratios of the forearm flexor muscles were completed at the end of each phase. CrM supplementation did not increase any of the outcome measurements except for plasma creatinine concentration (but not creatinine clearance). Thus, CrM supplementation at 5 g daily does not have any effects on muscle strength, body composition, or activities of daily living in patients with DM1, perhaps because of a failure of the supplementation to increase muscle PCr/beta-ATP content.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living
  • Adult
  • Body Mass Index
  • Creatine / blood
  • Creatine / therapeutic use*
  • Creatine / urine
  • Cross-Over Studies
  • Exercise Tolerance / drug effects
  • Exercise Tolerance / physiology
  • Female
  • Humans
  • Magnetic Resonance Spectroscopy
  • Male
  • Middle Aged
  • Muscle Proteins / blood
  • Muscle Proteins / urine
  • Muscle Weakness / drug therapy*
  • Muscle Weakness / etiology
  • Muscle, Skeletal / drug effects*
  • Muscle, Skeletal / metabolism
  • Muscle, Skeletal / physiopathology
  • Myotonic Dystrophy / blood
  • Myotonic Dystrophy / drug therapy*
  • Myotonic Dystrophy / urine
  • Phosphocreatine / metabolism*
  • Respiratory Function Tests
  • Treatment Failure


  • Muscle Proteins
  • Phosphocreatine
  • Creatine