title: Co-ingestion of carbohydrate and whey protein isolates enhance PGC-1α mRNA expression: a randomised, single blind, cross over study.
abstract: BACKGROUND
  Whey protein isolates (WPI) supplementation is known to improve resistance training adaptations. However, limited information is available on the effects of WPI plus carbohydrate (CHO) supplementation on endurance training adaptations.
  
  
  METHODS
  Six endurance trained male cyclists and triathletes (age 29 ± 4 years, weight 74 ± 2 kg, VO2 max 63 ± 3 ml oxygen. kg-1. Min-1, height 183 ± 5 cm; mean ± SEM) were randomly assigned to one of two dietary interventions in a single blind cross over design; CHO or CHO + WPI. Each dietary intervention was followed for 16 days which included the last 2 days having increased CHO content, representing a CHO loading phase. The dietary interventions were iso-caloric and carbohydrate content matched. On completion of the dietary intervention, participants performed an exercise bout, consisting of cycling for 60 min at 70% VO2 max, followed by time trial to exhaustion at 90% VO2 max and recovered in the laboratory for 6 hours. Blood samples and muscle biopsies were taken at various time points at rest and through the exercise trial and recovery.
  
  
  RESULTS
  Compared to CHO, CHO + WPI increased plasma insulin during recovery at 180 mins (P < 0.05) and peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) mRNA expression at the end of 6 hours of recovery (P < 0.05). Muscle glycogen did not differ between the two trials.
  
  
  CONCLUSIONS
  This study showed co-ingestion of CHO + WPI may have beneficial effects on recovery and adaptations to endurance exercise via, increased insulin response and up regulation of PGC-1α mRNA expression.
authors: Biomedical and Lifestyle Diseases Unit, College of Health and Biomedicine, Victoria University, PO Box 14428, Melbourne, VIC 8001, Australia. andrew.mcainch@vu.edu.au.
authors: Karen M
authors: KM
authors: Hill
authors: Christos G
authors: CG
authors: Stathis
authors: Esther
authors: E
authors: Grinfeld
authors: Alan
authors: A
authors: Hayes
authors: Andrew J
authors: AJ
authors: McAinch
references: J Nutr Biochem. 2003 May;14(5):251-8
references: 12832028
references: Int J Sport Nutr Exerc Metab. 2006 Oct;16(5):494-509
references: 17240782
references: J Physiol. 2008 Aug 1;586(15):3701-17
references: 18556367
references: J Sports Sci Med. 2004 Sep 01;3(3):131-8
references: 24482590
references: Sports Med. 2003;33(2):117-44
references: 12617691
references: Am J Clin Nutr. 2000 Jul;72(1):96-105
references: 10871567
references: J Appl Physiol (1985). 1992 May;72(5):1854-9
references: 1601794
references: J Appl Physiol (1985). 2011 Mar;110(3):834-45
references: 21030665
references: J Appl Physiol (1985). 2001 Aug;91(2):839-46
references: 11457801
references: Eur J Appl Physiol Occup Physiol. 1990;61(5-6):467-72
references: 2079068
references: Curr Opin Clin Nutr Metab Care. 2007 Jan;10(1):40-5
references: 17143053
references: Amino Acids. 2009 Jul;37(2):333-9
references: 18679613
references: Int J Sport Nutr Exerc Metab. 2009 Feb;19(1):1-17
references: 19403950
references: Am J Clin Nutr. 2007 Apr;85(4):996-1004
references: 17413098
references: Cell Metab. 2005 Jun;1(6):361-70
references: 16054085
references: FASEB J. 2002 Dec;16(14):1879-86
references: 12468452
references: Int J Sport Nutr Exerc Metab. 2007 Dec;17(6):521-43
references: 18156659
references: J Int Soc Sports Nutr. 2008 Oct 03;5:17
references: 18834505
references: Med Sci Sports Exerc. 2009 Mar;41(3):709-31
references: 19225360
references: Biochem Soc Trans. 2003 Dec;31(Pt 6):1267-9
references: 14641040
references: Br J Nutr. 2008 Jul;100(1):61-9
references: 18167171
references: J Appl Physiol (1985). 2010 Jul;109(1):126-34
references: 20466803
references: J Appl Physiol (1985). 2008 Apr;104(4):1029-36
references: 18239077
references: Am J Physiol Endocrinol Metab. 2011 Jun;300(6):E945-54
references: 21364122
references: Am J Physiol Endocrinol Metab. 2004 Oct;287(4):E712-20
references: 15165999
references: Am J Clin Nutr. 2000 Jul;72(1):106-11
references: 10871568
references: J Appl Physiol (1985). 2002 Oct;93(4):1337-44
references: 12235033
references: J Appl Physiol (1985). 2009 Sep;107(3):987-92
references: 19589961
references: Med Sci Sports Exerc. 2011 Dec;43(12):2249-58
references: 21606874
references: J Sports Sci. 2004 Jan;22(1):65-79
references: 14971434
references: Sports Med. 2003;33(11):783-93
references: 12959619
references: Exp Cell Res. 2010 Nov 1;316(18):3093-9
references: 20580710
references: J Physiol. 2011 Aug 15;589(Pt 16):4011-25
references: 21746787
references: Nature. 2007 Nov 29;450(7170):736-40
references: 18046414
references: J Sports Sci. 2006 Jul;24(7):709-21
references: 16766500
references: J Biol Chem. 2005 May 20;280(20):19587-93
references: 15767263
references: Pflugers Arch. 2006 May;452(2):125-39
references: 16437222
references: Methods. 2001 Dec;25(4):402-8
references: 11846609
references: Med Sci Sports Exerc. 1982;14(1):101-2
references: 7070249
references: Br J Sports Med. 2005 Jan;39(1):34-8
references: 15618337
references: Med Sci Sports Exerc. 2010 Oct;42(10):1843-52
references: 20195183
references: Appl Physiol Nutr Metab. 2009 Jun;34(3):465-72
references: 19448716
references: Nutr Metab (Lond). 2010 Jun 17;7:51
references: 20565767
references: Physiol Genomics. 2011 Sep 8;43(17):1004-20
references: 21730029