Systemic glucose level changes with a carbohydrate-restricted and higher protein diet combined with exercise.
OBJECTIVE
The authors' purpose in this study was to compare the effects of macronutrient intake on systemic glucose levels in previously sedentary participants who followed 1 of 4 diets that were either higher protein or high carbohydrate, while initiating an exercise program.


METHODS
The authors randomly assigned 94 sedentary participants to 1 of 4 diet groups consisting of Diet 1 (55% carbohydrate, 30% fat, 15% protein), Diet 2 (55% carbohydrate, 30% fat, 15% protein and caloric restriction), Diet 3 (40% carbohydrate, 30% fat, 25% protein), and Diet 4 (40% carbohydrate, 30% fat, 25% protein and caloric restriction) and followed recommended aerobic exercise prescriptions.


RESULTS
Repeated measures analyses of variance (ANOVA) revealed a significant time factor (p=.021) but no significant differences between diet groups (p=.207). A trend was evident in the higher protein groups, with a 5.2% decrease in glucose levels with Diet 3 and 5.0% with Diet 4. Although glucose levels changed over time with the greatest changes in the 2 higher protein diets, levels were not significantly different within participants.


CONCLUSIONS
The results of the study indicate that systemic glucose availability was affected by higher protein consumption in Diet 3 participants, with the same trend in Diet 4 participants, although nonsignificant. These findings demonstrate that consuming a lower carbohydrate diet for 12 weeks can possibly change systemic glucose levels.
Bowden
Rodney G
RG
Baylor University's Department of Health, Human Performance and Recreation, Center for Exercise, Waco, TX 76798, USA. Rodney_Bowden@baylor.edu
Lanning
Beth A
BA
Doyle
Eva I
EI
Slonaker
Becky
B
Johnston
Holly M
HM
Scanes
Georgene
G
D000273:Adipose Tissue / Q000000981:diagnostic imaging; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001786:Blood Glucose / Q000032:analysis* / Q000378:metabolism; D050528:Diet, Carbohydrate-Restricted; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage* / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000378:metabolism; D002149:Energy Intake / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D006266:Health Education; D006801:Humans; D008297:Male; D011859:Radiography; D013334:Students / Q000706:statistics & numerical data; D014495:Universities
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins