Su-Fen Liao, Mallikarjuna Korivi, Jung-Piao Tsao, Chun-Ching Huang, Chia-Chen Chang and I-Shiung Cheng* Pages 981 - 988 ( 8 )
Background: Capsinoids (CSN), the novel non-pungent capsaicin analogs have been reported to promote metabolic health and exercise tolerance. However, the effect of CSN on fat oxidation and changes in skeletal muscle glycogen levels during post-exercise recovery has not been investigated in humans.
Purpose: We examined the effect of CSN supplementation on energy reliance, glycogen resynthesis and molecular proteins in the skeletal muscle of young adults during post-exercise recovery.
Methods: In this crossover-designed study, nine healthy adult male volunteers (aged 21.4±0.2 years, BMI 21.9±1.3 kg/m2) completed a 60-min cycling exercise at 70% VO2max. Participants consumed either CSN (12 mg, single dosage) or placebo capsules with a high-carbohydrate meal (2 g carb/kg bodyweight) immediately after exercise. Biopsied muscle samples (vastus lateralis), blood, and gaseous samples were obtained during 3h postexercise recovery period.
Results: We found that oral CSN supplementation right after exercise significantly altered the energy reliance on fat oxidation during recovery. This was evidenced by lower respiratory exchange ratio (RER) and higher fat oxidation rate in CSN trial. Despite this, acute CSN dosage does not contribute in enhancing the glycogen replenishment in skeletal muscle during 3h recovery. We identified no significant differences in postprandial glucose and insulin area under the curve in both trials. Western blot data showed an increased muscle GLUT4 expression, but no significant response of p-Akt/Akt ratio with CSN during post-exercise recovery.
Conclusion: Our findings conclude that acute CSN intake could change energy reliance on fat oxidation but is unable to enhance muscle glycogen resynthesis during post-exercise recovery. Thus, ergogenic properties of CSN in relevance to muscle glycogen restoration following exercise needs to be further investigated in young adults.
Nutraceutical supplements, ergogenic aids, substrate oxidation, muscle glycogen, supplementation, capsinoids.
Department of Physical Medicine and Rehabilitation, Changhua Christian Hospital, Changhua City, Exercise and Metabolism Research Center, College of Physical Education and Health Sciences, Zhejiang Normal University, Jinhua City, Zhejiang, Center for General Education, National Taichung University of Education, Taichung City, Department of Exercise and Health Science, National Taipei University of Nursing and Health Sciences, Taipei City, Physical Education Center, National Dong Hwa University, Hualien City, Department of Physical Education, National Taichung University of Education, Taichung City