PMID- 9688623
OWN - NLM
STAT- MEDLINE
DCOM- 19980916
LR  - 20190320
IS  - 0002-9513 (Print)
IS  - 0002-9513 (Linking)
VI  - 275
IP  - 2
DP  - 1998 Aug
TI  - Dietary carbohydrate and postexercise synthesis of proglycogen and macroglycogen 
      in human skeletal muscle.
PG  - E229-34
LID - 10.1152/ajpendo.1998.275.2.E229 [doi]
AB  - This study examined the role of carbohydrate (CHO) ingestion on the resynthesis 
      of two pools of glycogen, proglycogen (PG) and macroglycogen (MG), in human 
      skeletal muscle. Nine males completed an exhaustive glycogen depletion exercise 
      bout at 70% maximal O2 consumption on two occasions. Subsequent 48-h dietary 
      interventions consisted of either high (HC, 75% of energy intake) or low (LC, 32% 
      of energy intake) CHO diets. Muscle biopsies were taken at exhaustion (EXH) and 
      4, 24, and 48 h later. The total muscle glycogen (Gt) at EXH for the HC and LC 
      conditions was not significantly different, and the MG represented approximately 
      12% of the Gt. From EXH to 4 h, there was an increase in the PG only for HC and 
      no change in MG in either diet (P < 0.05). From 4 to 24 h, the concentration of 
      PG increased in both conditions (P < 0.05). Between 24 and 48 h, in HC the 
      majority of the increase in Gt was due to the MG pool (P < 0.05). The MG and PG 
      concentrations for HC were significantly greater than for LC at 24 and 48 h (P < 
      0.05). At 48 h the MG represented 40% of the Gt for the HC diet and only 21% for 
      the LC diet. There was no change in the net rates of synthesis of PG or MG over 
      48 h for LC (P < 0.05). The net rate of PG synthesis from 0 to 4 h for HC was 16 
      +/- 1.68 mmol glucosyl units . kg dry wt-1 . h-1, which was threefold greater 
      than for LC (P < 0. 05). The net rate of PG synthesis decreased significantly 
      from 4 to 24 h for HC, whereas the net rate of MG synthesis was not different 
      over 48 h but was significantly greater than in LC (P < 0.05). The two pools are 
      synthesized at very different rates; both are sensitive to CHO, and the 
      supercompensation associated with HC is due to a greater synthesis in the MG 
      pool.
FAU - Adamo, K B
AU  - Adamo KB
AD  - Department of Human Biology and Nutritional Sciences, University of Guelph, 
      Guelph, Ontario N1G 2W1, Canada.
FAU - Tarnopolsky, M A
AU  - Tarnopolsky MA
FAU - Graham, T E
AU  - Graham TE
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Am J Physiol
JT  - The American journal of physiology
JID - 0370511
RN  - 0 (Dietary Carbohydrates)
RN  - 9005-79-2 (Glycogen)
SB  - IM
MH  - Adult
MH  - *Dietary Carbohydrates
MH  - Energy Intake
MH  - Exercise/*physiology
MH  - Glycogen/analogs & derivatives/*biosynthesis
MH  - Humans
MH  - Male
MH  - Muscle Fatigue/physiology
MH  - Muscle, Skeletal/*physiology
MH  - Oxygen Consumption
MH  - Physical Exertion/*physiology
MH  - Time Factors
EDAT- 1998/08/04 00:00
MHDA- 1998/08/04 00:01
CRDT- 1998/08/04 00:00
PHST- 1998/08/04 00:00 [pubmed]
PHST- 1998/08/04 00:01 [medline]
PHST- 1998/08/04 00:00 [entrez]
AID - 10.1152/ajpendo.1998.275.2.E229 [doi]
PST - ppublish
SO  - Am J Physiol. 1998 Aug;275(2):E229-34. doi: 10.1152/ajpendo.1998.275.2.E229.