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Published on: September 28, 2016
Postexercise increase of free fatty acids. A qualitative indicator for free fatty acid utilisation during exercise?
C Vobejda1, G Simon, E Zimmermann
1Sportmedizin, University Bielefeld, Bielefeld, Germany. christian.vobejda@uni-bielefeld.de
Aim:
The purpose of this study was to verify the hypothesis that the postexercise increase (PEI) of plasma free fatty acid (FFA) concentrations after cessation of exercise is a suitable qualitative indicator for the FFA utilisation during the foregoing exercise.
Methods:
Fourteen, 17 and 23 healthy subjects participated in 3 test series performing several prolonged exercise protocols (PEP) on a bicycle ergometer. During and after cessation of the PEP heart frequency, lactate and FFA were measured.
Results:
Fasting resulted in an increase of PEI (90%, p<0.05) and the synergistic use of upper body muscles during cycling caused a significant rise of PEI compared to "regular" cycling (39%, p<0.01). Increasing workload step by step produced continuously rising PEI (p<0.05), only from 42% to 50% of maximal workload PEI decreased by 17% (p=n.s.).
Conclusion:
The results support the hypothesis that PEI is a suitable qualitative indicator for FFA utilisation during a foregoing exercise. Furthermore the results indicate that there is a maximum of FFA utilisation in the legs at 40% of maximum workload during cycling and that the upper body muscles contribute substantially to total body FFA turnover at high inten-sities, an aspect to which possibly too little attention has been paid to when quantifying FFA turnover during cycling.
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