Journal of Applied Physiology, Vol 39, Issue 2 247-250, Copyright © 1975 by American Physiological Society
Turnover of free fatty acids during recovery from exercise
L. Hagenfeldt and J. Wahren
The turnover of plasma free fatty acid (FFA) was studied during the
recovery from exercise with the aid of a continuous infusion of 14C-labeled
oleic acid. Arterial FFA reached a maximum of twice the exercise value
after 6 min of recovery and was still 75% above the basal level after 20
min. Within 2 min after exercise, plasma radioactivity had increased and
the specific activity of plasma oleic acid had fallen. The rate of uptake
of FFA from the plasma pool rsoe by 40% during the first minutes after
exercise. The rate of release of FFA to the plasma pool showed a peak 2 min
after exercise and was thereafter about 40 mumol/min lower than the rate of
uptake. The fractional turnover of FFA decreased to resting levels within
5-10 min after exercise. It is concluded that the postexercise peak in
arterial FFA is a consequence of augmented release of FFA into the plasma
pool above the level during exercise, possibly related to the release of
sympathetic vasoconstrictor tone. As a consequence, the rate of removal of
FFA rises at the end of exercise and remains augmented above the basal
level for as long as the arterial concentration is increased.
