AbstractPurpose and Methods:
Breakdown rates of very low density lipoprotein triacylglycerols (VLDL-TAG) were quantified before (3 h), during (45 min), and after (3 h) moderate physical exercise at 40% JOURNAL/mespex/04.02/00005768-200405000-00007/ENTITY_OV0312/v/2017-07-20T222934Z/r/image-png2 max in young sedentary subjects (four male and four female, age 29.8 ±1.6 yr, BMI 24.1 ± 0.9 kg·m−2, JOURNAL/mespex/04.02/00005768-200405000-00007/ENTITY_OV0312/v/2017-07-20T222934Z/r/image-png2max 37.0 ± 1.7 mL·kg−1·min−1), using boluses of 2H5-glycerol (100 μ mol·kg−1) and 2H2-palmitate (6.6 μ mol·kg−1). The catabolic rates of VLDL-TAG were calculated from the decay in the isotopic enrichment using a single-pool model. The results were compared with those obtained during 6 h of rest in five of the same volunteers.Results:
VLDL-TAG concentration remained constant throughout the study with exercise (P = NS). The fractional catabolic rate was nearly doubled from rest to exercise (P < 0.05 vs rest) and increased to an even greater extent during the early phase of recovery (P < 0.001 vs rest). During the late recovery phase, the value returned to the preexercise value (P = NS vs rest). The values for the absolute catabolic rate (kabs) followed the same trend.Conclusion:
VLDL-TAG turnover was increased during exercise and during the early phase of recovery.