Effect of protein intake and physical activity on 24-h pattern and rate of macronutrient utilization

TY - JOUR

T1 - Effect of protein intake and physical activity on 24-h pattern and rate of macronutrient utilization

AU - Forslund, Anders

AU - El-Khoury, Antoine E

AU - Olsson, Roger M

AU - Sjödin, Anders Mikael

AU - Hambraeus, Leif

AU - Young, Vernon R

PY - 1999

Y1 - 1999

N2 - Effects of moderate physical activity (90 min at 45-50% of maximal O2 uptake 2 times daily) and 'high, (2.5 g protein · kg-1 · day-1, n = 6) or 'normal' protein intake (1.0 g protein · kg-1 · day-1, n = 8) on the pattern and rate of 24-h macronutrient utilization in healthy adult men were compared after a diet-exercise-adjustment period of 6 days. Energy turnover (ET) was determined by indirect and direct (suit) calorimetry, and 'protein oxidation' was determined by a 24-h continuous intravenous infusion of [1- 13C]leucine. Subjects were in slight positive energy balance during both studies. Protein contributed to a higher (22 vs. 10%) and carbohydrate (CHO) a lower (33 vs. 58%) proportion of total 24-h ET on the high- vs. normal- protein intake. The highest contribution of fat to ET was seen postexercise during fasting (73 and 61% of ET for high and normal, respectively). With the high-protein diet the subjects were in a positive protein (P < 0.001) and CHO balance (P < 0.05) and a negative fat balance (P < 0.05). The increased ET postexercise was not explained by increased rates of urea production and/or protein synthesis.

AB - Effects of moderate physical activity (90 min at 45-50% of maximal O2 uptake 2 times daily) and 'high, (2.5 g protein · kg-1 · day-1, n = 6) or 'normal' protein intake (1.0 g protein · kg-1 · day-1, n = 8) on the pattern and rate of 24-h macronutrient utilization in healthy adult men were compared after a diet-exercise-adjustment period of 6 days. Energy turnover (ET) was determined by indirect and direct (suit) calorimetry, and 'protein oxidation' was determined by a 24-h continuous intravenous infusion of [1- 13C]leucine. Subjects were in slight positive energy balance during both studies. Protein contributed to a higher (22 vs. 10%) and carbohydrate (CHO) a lower (33 vs. 58%) proportion of total 24-h ET on the high- vs. normal- protein intake. The highest contribution of fat to ET was seen postexercise during fasting (73 and 61% of ET for high and normal, respectively). With the high-protein diet the subjects were in a positive protein (P < 0.001) and CHO balance (P < 0.05) and a negative fat balance (P < 0.05). The increased ET postexercise was not explained by increased rates of urea production and/or protein synthesis.

KW - Carbohydrate

KW - Direct calorimetry

KW - Energy turnover

KW - Fat

KW - Indirect calorimetry

KW - Macronutrient utilization

KW - Obesity

KW - Physical exercise

KW - Protein

KW - Stable isotopes

UR - http://www.scopus.com/inward/record.url?scp=0033045543&partnerID=8YFLogxK

U2 - 10.1152/ajpendo.1999.276.5.E964

DO - 10.1152/ajpendo.1999.276.5.E964

M3 - Journal article

C2 - 10329992

AN - SCOPUS:0033045543

SN - 1522-1555

VL - 276

SP - E964-E976

JO - A J P: Endocrinology and Metabolism (Online)

JF - A J P: Endocrinology and Metabolism (Online)

IS - 5

ER -