PMID- 17146316
OWN - NLM
STAT- MEDLINE
DCOM- 20070130
LR  - 20131121
IS  - 0195-9131 (Print)
IS  - 0195-9131 (Linking)
VI  - 38
IP  - 12
DP  - 2006 Dec
TI  - Effects of chromium supplementation on glycogen synthesis after high-intensity 
      exercise.
PG  - 2102-9
AB  - PURPOSE: Chromium enhances insulin signaling and insulin-mediated glucose uptake 
      in cultured cells. We investigated the effect of chromium on glycogen synthesis 
      and insulin signaling in humans. METHODS: Sixteen overweight men (BMI = 31.1 +/- 
      3.0 kg.m) were randomly assigned to supplement with 600 microg.d chromium as 
      picolinate (Cr; N = 8) or a placebo (Pl; N = 8). After 4 wk of supplementation, 
      subjects performed a supramaximal bout of cycling exercise to deplete muscle 
      glycogen, which was followed by high-glycemic carbohydrate feedings for the next 
      24 h. Muscle biopsies were obtained at rest, immediately after exercise, and 2 
      and 24 h after exercise. RESULTS: Elevations in glucose and insulin during 
      recovery were not different, but the lactate response was significantly higher in 
      Cr. There was a significant depletion in glycogen immediately after exercise, an 
      increase at 2 h, and a further increase above rest at 24 h (P < 0.05). The rate 
      of glycogen synthesis during the 2 h after exercise was not different between 
      groups (Cr: 25.8 +/- 8.0 and Pl: 17.1 +/- 4.7 mmol.kg.h). Glycogen synthase 
      activity was significantly increased immediately after exercise in both groups. 
      Muscle phosphatidylinositol 3-kinase (PI 3-kinase) activity decreased immediately 
      after exercise and increased at 2 h (P < 0.05), with a trend for a lower PI 
      3-kinase response in Cr (P = 0.08). CONCLUSIONS: Chromium supplementation did not 
      augment glycogen synthesis during recovery from high-intensity exercise and 
      high-carbohydrate feeding, although there was a trend for lower PI 3-kinase 
      activity.
FAU - Volek, Jeff S
AU  - Volek JS
AD  - Human Performance Laboratory, Department of Kinesiology, University of 
      Connecticut, Storrs, CT 06269-1110, USA. jeff.volek@uconn.edu
FAU - Silvestre, Ricardo
AU  - Silvestre R
FAU - Kirwan, John P
AU  - Kirwan JP
FAU - Sharman, Matthew J
AU  - Sharman MJ
FAU - Judelson, Daniel A
AU  - Judelson DA
FAU - Spiering, Barry A
AU  - Spiering BA
FAU - Vingren, Jakob L
AU  - Vingren JL
FAU - Maresh, Carl M
AU  - Maresh CM
FAU - Vanheest, Jaci L
AU  - Vanheest JL
FAU - Kraemer, William J
AU  - Kraemer WJ
LA  - eng
PT  - Journal Article
PT  - Randomized Controlled Trial
PL  - United States
TA  - Med Sci Sports Exerc
JT  - Medicine and science in sports and exercise
JID - 8005433
RN  - 0 (Iron Chelating Agents)
RN  - 0 (Picolinic Acids)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 9005-79-2 (Glycogen)
RN  - EC 2.7.1.- (Phosphatidylinositol 3-Kinases)
RN  - QZV2W997JQ (picolinic acid)
SB  - IM
MH  - Adult
MH  - Biopsy, Needle
MH  - Diet, Carbohydrate-Restricted
MH  - *Dietary Supplements
MH  - Double-Blind Method
MH  - *Exercise Test
MH  - Glycogen/*biosynthesis
MH  - Humans
MH  - Iron Chelating Agents/*pharmacology
MH  - Lactic Acid/blood
MH  - Male
MH  - Muscle, Skeletal/metabolism/pathology
MH  - Overweight
MH  - Phosphatidylinositol 3-Kinases/metabolism
MH  - *Physical Endurance
MH  - Picolinic Acids/*pharmacology
MH  - Time Factors
EDAT- 2006/12/06 09:00
MHDA- 2007/01/31 09:00
CRDT- 2006/12/06 09:00
PHST- 2006/12/06 09:00 [pubmed]
PHST- 2007/01/31 09:00 [medline]
PHST- 2006/12/06 09:00 [entrez]
AID - 00005768-200612000-00009 [pii]
AID - 10.1249/01.mss.0000235353.09061.54 [doi]
PST - ppublish
SO  - Med Sci Sports Exerc. 2006 Dec;38(12):2102-9. doi: 
      10.1249/01.mss.0000235353.09061.54.