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document
Endurance training has little effect on active muscle free fatty acid , lipoprotein cholesterol , or triglyceride net balances . We evaluated the hypothesis that net leg total FFA , LDL-C , and TG uptake and HDL-C release during moderate-intensity cycling exercise would be increased following endurance training . Eight sedentary men ( 26 +/- 1 yr , 77.4 +/- 3.7 kg ) were studied in the postprandial state during 90 min of rest and 60 min of exercise twice before ( 45 % and 65 % V ( O2 peak ) ) and twice after 9 wk of endurance training ( 55 % and 65 % posttraining V ( O2 peak ) ) . Measurements across an exercising leg were taken to be a surrogate for active skeletal muscle . To determine limb lipid exchange , femoral arterial and venous blood samples drawn simultaneously at rest and during exercise were analyzed for total and individual FFA ( e.g. , palmitate , oleate ) , LDL-C , HDL-C , and TG concentrations , and limb blood flow was determined by thermodilution . The transition from rest to exercise resulted in a shift from net leg total FFA release ( -44 +/- 16 micromol/min ) to uptake ( 193 +/- 49 micromol/min ) that was unaffected by either exercise intensity or endurance training . The relative net leg release and uptake of individual FFA closely resembled their relative abundances in the plasma with approximately 21 and 41 % of net leg total FFA uptake during exercise accounted for by palmitate and oleate , respectively . Endurance training resulted in significant changes in arterial concentrations of HDL-C ( 49 +/- 5 vs. 52 +/- 5 mg/dl , pre vs. post ) and LDL-C ( 82 +/- 9 vs. 76 +/- 9 mg/dl , pre vs. post ) , but there was no net TG or LDL-C uptake or HDL-C release across the resting or active leg before or after endurance training . In conclusion , endurance training favorably affects blood lipoprotein profiles , even in young , healthy normolipidemic men , but muscle contractions per se have little effect on net leg LDL-C , or TG uptake or HDL-C release during moderate-intensity cycling exercise . Therefore , the favorable effects of physical activity on the lipid profiles of young , healthy normolipidemic men in the postprandial state are not attributable to changes in HDL-C or LDL-C exchange across active skeletal muscle .
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Intervention_Physical
90 min of rest and 60 min of exercise twice
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Intervention_Physical
9 wk of endurance training
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Intervention_Physical
Endurance training
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Outcome_Other
free fatty acid
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Outcome_Physical
lipoprotein cholesterol
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Outcome_Physical
triglyceride
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Outcome_Physical
net leg total FFA
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Outcome_Physical
LDL-C
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Outcome_Physical
TG uptake
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Outcome_Physical
HDL-C release
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Outcome_Physical
limb lipid exchange
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Outcome_Physical
LDL-C
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Outcome_Physical
HDL-C
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Outcome_Physical
TG concentrations
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Outcome_Physical
limb blood flow
26123
Outcome_Physical
total FFA release
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Outcome_Physical
arterial concentrations of HDL-C
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Outcome_Physical
LDL-C
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Outcome_Physical
net TG or LDL-C uptake
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Outcome_Physical
HDL-C release
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Outcome_Physical
blood lipoprotein profiles
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Outcome_Physical
leg LDL-C
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Outcome_Physical
TG uptake
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Outcome_Physical
HDL-C release
26132
Outcome_Physical
HDL-C
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Outcome_Physical
LDL-C
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Participant_Sample-size
Eight
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Participant_Sex
men
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Participant_Age
26 +/- 1 yr ,
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Participant_Age
young
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Participant_Sex
men
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Participant_Age
young
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Participant_Condition
normolipidemic
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Participant_Sex
men