Effects of ingesting low glycemic index carbohydrate food for the sahur meal on subjective, metabolic and physiological responses, and endurance performance in Ramadan fasted men

Abstract

Purpose: To investigate the effect of low glycemic index (LGI) carbohydrate meal on subjective, metabolic and physiological responses, and endurance performance in the Ramadan fasted state. Methods: During Ramadan, 12 Muslim men, in a randomized and crossover design, ingested for the sahur meal (i.e. last meal before commencement of the day’s fast), either LGI (glycemic index = 37) or mixed (CON; ∼57) meal of equivalent macro-nutrient. At ∼12 h post-prandial, subjects completed a 60 min continuous run. Results: There were no significant differences between the two meals for ratings in perceived satiety, fullness, appetite and mood states. During steady-state exercise, there were no significant differences in metabolic and physiological measures. In the time-trial, distance ran was significantly lower in LGI versus CON meal trial, but with a corresponding lower perceived exertion in the LGI trial. Conclusion: Compared to CON, ingesting LGI as the sahur meal did not provide any metabolic, physiological or performance benefits during endurance run performed 12 h post-prandial in Ramadan fasted state.

• Blood glucose concentration
• exercise
• perceived exertion
• religious fast
• satiety