Co-ingestion of caffeine and carbohydrate after meal does not improve performance at high-intensity intermittent sprints with short recovery times

Apr 22, 2014European journal of applied physiology

Taking caffeine and carbs after a meal does not improve short-recovery high-intensity sprint performance

AI simplified

Circadian Biology on OpenScience ↗PubMed ↗DOI ↗

Abstract

Co-ingestion of caffeine and carbohydrates resulted in a 5.2% reduction in total work during high-intensity intermittent sprints.

No significant differences in peak power output and mean power output were observed between the trials.
Fatigue increased by 24.7-25.7% at the end stage of the high-intensity sprints with caffeine and carbohydrates compared to placebo.
Blood lactate levels rose by 11.1% during the sprints with caffeine and carbohydrates relative to placebo.
Blood glucose concentrations were elevated throughout the high-intensity sprint testing when caffeine and carbohydrates were consumed.
Cortisol levels increased with caffeine and carbohydrate intake, but no significant change in testosterone concentrations was noted.

AI simplified

PURPOSE: To determine the effects of co-ingesting caffeine (CAF) and carbohydrate (CHO) on high-intensity intermittent sprints (HIS) performance and physiological responses.

METHODS: Twelve active males underwent 4 interventions at least 7 days apart in a randomized, double-blind, placebo-controlled, balanced trial. A meal contained 65 % CHO was provided 2 h before the HIS test. Participants ingested the placebo (PLA) or CAF (6 mg kg(-1) BW) 1 h before taking an HIS test, and ingested a PLA or CHO solution (0.8 g kg(-1) BW) before undergoing the testing protocol. The HIS protocol comprised ten sets of 5 × 4-s sprints on a cycle ergometer with a 2-min recovery between each set.

RESULTS: There was no significant difference between peak power output and mean power output between trials (p > 0.05). Compared with PLA, CAF + CHO resulted in a 5.2 % reduction in total work, corresponding to a 24.7-25.7 % increase in fatigue at the end stage of the HIS. The administration of CAF + CHO supplementation also resulted in an 11.1 % increase in blood lactate, and elevated blood glucose concentrations throughout HIS testing compared with PLA (p < 0.05). Cortisol concentrations also increased with CAF + CHO intake compared with PLA; however, there was no significant effect of CAF + CHO supplementation on testosterone concentrations.

CONCLUSION: Co-ingestion of CAF and CHO did not improve high-intensity sprint cycling performance or reduce fatigue in active males. Moreover, combined CAF and CHO supplementation might facilitate catabolism during prolonged high-intensity intermittent exercise.

Full Text

Full text is available at the source.

View full text (PDF) ↗View full text (HTML) ↗View full text ↗

Co-ingestion of caffeine and carbohydrate after meal does not improve performance at high-intensity intermittent sprints with short recovery times

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief