J Strength Cond Res 2011, 25:3461–3471.PubMedCrossRef 13. Tyrrell VJ, Richards G, Hofman P, Gillies GF, Robinson E, Cutfield WS: Foot-to-foot bioelectrical impedance analysis: a valuable tool for the measurement of body composition in children. Int J Obes 2001, 25:273–278.CrossRef 14. Utter AC, Nieman DC, Ward AN, Butterworth DE: Use of the leg-to-leg bioelectrical impedance method in assessing body composition MEK inhibitor change in obese women. Am J Clin Nutr 1999, 69:603–607.PubMed 15. Swartz AM, Evan MJ, King GA, Thompson DL: Evaluation of a foot-to-foot bioelectrical impedance analyser in highly active, moderately

active and less active young men. Br J Nutr 2002, 88:205–210.PubMedCrossRef 16. Parker L, Reilly JJ, Christine S, Wells JCK, Pitsiladis Y: Validity of six

field and laboratory methods for measurement of body composition in boys. Obes Res 2003, 11:852–858.PubMedCrossRef 17. du Vigneaud V, Simmonds S, Chandler Fosbretabulin in vivo JP, Cohn M: A further investigation of the role of betaine in transmethylation reactions in vivo. J Biol Chem 1946, 165:639–648.PubMed 18. Storch KJ, Wagner DA, Young VR: Methionine kinetics in adult men: effects of dietary betaine on L-[2H3-methyl-1–13C]methionine. Am J Clin Nutr 1991, 54:386–394.PubMed 19. Wise CK, Cooney CA, Ali SF, Poirier LA: Measuring S-adenosylmethionine in whole blood, red blood cells and cultured cells using a fast preparation method and high-performance liquid chromatography. J Chromatogr B Biomed Sci Appl 1997, 696:145–152.PubMedCrossRef 20. Branch JD: Effect of creatine LGX818 clinical trial supplementation on body composition and performance: a meta-analysis.

Int J Sport Nutr Exerc Metab 2003, 13:198–226.PubMed 21. Del Favero S, Roschel H, Artioli G, Ugrinowitsch C, Tricoli V, Costa A, Barroso R, Negrelli Megestrol Acetate AL, Otaduy MC, da Costa Leite C, Lancha-Junior AH, Gualano B: Creatine but not betaine supplementation increases muscle phosphorylcreatine content and strength performance. Amino Acids 2011. doi: 10.1007/s00726–011–0972–5 22. Kumar R: Role of naturally occurring osmolytes in protein folding and stability. Arch Biochem Biophys 2009, 491:1–6.PubMedCrossRef 23. Bounedjah O, Hamon L, Savarin P, Desdorges B, Curmi PA, Pastre D: Macromolecular crowding regulates the assembly of mRNA stress granules after osmotic stress: a new role for compatible osmolytes. J Biol Chem 2011. doi: 10.1074/jbc.M111.292748 jbc.M111.292748 24. Ueland PM: Choline and betaine in health and disease. J Inherit Metab Dis 2011, 34:3–15.PubMedCrossRef 25. Kraemer WJ, Bailey BL, Clark JE, Apicella J, Lee EC, Comstock BE, Dunn-Lewis C, Volek J, Kupchak B, Anderson JM, Craig SAS, Mares CM: The influence of betaine supplementation on work performance and endocrine function in men [abstract]. J Strength Cond Res 2011, 25:s100-s101. 26.