TY - ABST

T1 - Impact of moderate exercise upon 24h leucine and nitrogen kinetics

T2 - 24h studies at high protein intake and neutral energy balance, l Hambraeus

AU - Forslund, A

AU - El-Khoury, Antoine B

AU - Olsson, Roger M

AU - Sjödin, Anders Mikael

AU - Atkinson, Alan

AU - Date, S

AU - Young, Vernon R

PY - 1996

Y1 - 1996

N2 - We have previously found that total 24h leucine (leu) and nitrogen (N) balances were neutral when 180 min of exercise (45-50% VO2max) were performed daily (90 min in fasting and 90 min in feeding) for 7 consecutive days, under conditions of neutral energy balance and a dietary protein intake of Ig· kg-1· d-1. We have now assessed whether an increase in protein intake would induce a retention of leu and/or N. Four healthy men were studied on day 7, of a diet supplying 2.5 g· kg-1·d2, by using primed constant intravenous infusions of [1-13C]leu and [15N15N]urea, in combination with both indirect and direct (suit) calorimetry. 24h leu balance (input-oxidation) was+16.1±8.4mg- kg-1·d-1 (MeaniSD) for an intake of 277 mg leu· kg-1·d-1. Hence, leu balance was positive by about 5.8% of intake. 180 min exercise activity induced a total increase in daily leucine oxidation by 4.1%. 24h N excretion (corrected for urea N pool size) was 366±29 mg N· kg-1 · d-1, for an intake of 391 mg N·kg-1·d-1. These results indicate a mild positive retention of leu (p<0.01) and N (p<0,01)under these conditions. It is possible that a more beneficial effect of an increase in protein intake would more likely be found when energy balance is negative. NIH grants RR88, DK15856, SJFR 50.0204/94, CIF 55194.

AB - We have previously found that total 24h leucine (leu) and nitrogen (N) balances were neutral when 180 min of exercise (45-50% VO2max) were performed daily (90 min in fasting and 90 min in feeding) for 7 consecutive days, under conditions of neutral energy balance and a dietary protein intake of Ig· kg-1· d-1. We have now assessed whether an increase in protein intake would induce a retention of leu and/or N. Four healthy men were studied on day 7, of a diet supplying 2.5 g· kg-1·d2, by using primed constant intravenous infusions of [1-13C]leu and [15N15N]urea, in combination with both indirect and direct (suit) calorimetry. 24h leu balance (input-oxidation) was+16.1±8.4mg- kg-1·d-1 (MeaniSD) for an intake of 277 mg leu· kg-1·d-1. Hence, leu balance was positive by about 5.8% of intake. 180 min exercise activity induced a total increase in daily leucine oxidation by 4.1%. 24h N excretion (corrected for urea N pool size) was 366±29 mg N· kg-1 · d-1, for an intake of 391 mg N·kg-1·d-1. These results indicate a mild positive retention of leu (p<0.01) and N (p<0,01)under these conditions. It is possible that a more beneficial effect of an increase in protein intake would more likely be found when energy balance is negative. NIH grants RR88, DK15856, SJFR 50.0204/94, CIF 55194.

UR - http://www.scopus.com/inward/record.url?scp=33749144894&partnerID=8YFLogxK

M3 - Conference abstract in journal

AN - SCOPUS:33749144894

VL - 10

SP - A474

JO - F A S E B Journal

JF - F A S E B Journal

SN - 0892-6638

IS - 3

ER -