Pre-Exercise Carbohydrate Status Influences Carbohydrate-Mediated Attenuation of Post-Exercise Cytokine Responses

• Published in: International journal of sports medicine 2008-12, Vol.29 (12), p.1003-1009
• Main Authors: Cox, A. J., Pyne, D. B., Cox, G. R., Callister, R., Gleeson, M.
• Format: Article
• Language: English
• Subjects: Adult; Bicycling - physiology; Biological and medical sciences; Blood Glucose; Cytokines; Dietary Carbohydrates - metabolism; Energy Metabolism; Ergometry - instrumentation; Exercise - physiology; Exercise Test; Fundamental and applied biological sciences. Psychology; Humans; Immunology; Male; Nutritional Status; Oxygen Consumption; Time Factors; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports
• ISSN: 0172-4622; 1439-3964
• DOI: 10.1055/s-2008-1038753

Abstract Most studies investigating the effects of acute carbohydrate (CHO) ingestion on post-exercise cytokine responses have involved fasted athletes. This study characterised the effects of acute CHO beverage ingestion preceded by consumption of a CHO-containing pre-exercise meal. Sixteen highly-trained male cyclists/triathletes (age: 30.6 ± 5.6 y; V˙O 2max : 64.8 ± 4.7 ml · kg · min −1 [mean ± SD]) undertook two cycle ergometry trials involving randomised consumption of a 10 % CHO beverage (15 mL · kg −1  · hr −1 ) or water (H 2 O). Trials were undertaken 2 h after a breakfast providing 2.1 g CHO · kg −1 body mass (BM) (48 kJ · kg −1  BM) and consisted of 100 min steady state cycle ergometry at 70 % V˙O 2max followed by a time trial of ∼ 30 min duration. Blood samples were collected pre-, post- and 1 h post-exercise for measurement of Interleukin (IL)-6, IL-8, IL-10 and IL-1ra. Time-trial performance was not substantially different between CHO and H 2 O trials (4.5 %, p = 0.42). Neither IL-6 nor IL-8 responses were substantially reduced in the CHO compared to the H 2 O trial. There was a substantial reduction in IL-10 (32 %, p = 0.05) and IL-1ra (43 %, p = 0.02) responses at 1 h post-exercise with CHO compared to H 2 O ingestion. In conclusion, the previously shown attenuating effects of CHO ingestion during exercise on cytokine responses appear reduced when athletes consume a CHO-containing pre-exercise meal.