The influence of different concentrations of flavanol chocolate bars under acute supplement conditions on exercise and performance

Abstract

Objective: The purpose of this study was to assess the effects an acute dosage of different flavanol concentrations in a dark chocolate bar has on physiological parameters during steady state (SS) and incremental exercise. Methods:In a double-blind, randomised, crossover study, fifteen healthy participants with a mean ± SD age of 30 ± 7 years; stature 176.8 ± 8.6 cm and body mass 80.3 ± 8.4 kg supplemented with high flavanol (HF) (1060mg), moderate flavanol (MF) (746mg), low flavanol (LF) (406mg) or a control (CON) (88mg) chocolate bar (~34 grams), 2 hours prior to 40 minutes of SS cycling (80% gas exchange threshold) followed by an incremental test to volitional fatigue. During the SS cycle oxygen consumption (̇2), respiratory exchange ratio (RER) and heart rate (HR) were continuously monitored. Plasma samples were collected prior to commencing exercise to determine nitrate (NO 3 -) and nitrite (NO 2 -) levels under each condition.Results: There was no observed effect between flavanol concentrations on ̇2 , RER and HR during SS cycling (P>0.05). ̇2, peak power, HR peak and RER peak also did not significantly differ between conditions (P>0.05). There was a small trend for higher plasma NO 2 -levels following higher flavanol concentration, however this did not reach statistical significance (P>0.05). Conclusion:Acute supplementation with cocoa of differing flavanol concentrations does not appear to have any effect on exercise and performance. It is plausible that longer flavanol supplementation periods might have greater accumulative effects and thus may potentially elicit a larger effect.

The effects of cocoa flavanols on indices of muscle recovery and exercise performance: a narrative review

“…This may suggest that some individuals are potential ‘non-responders’ to CF supplementation, or that the differences seen were due to chance and not the allocated treatments. Other studies that investigated performance and CF supplementation found no significant differences between groups for 5 km time trial performance or V̇ O 2max [ 41 , 79 , 86 ]. However, recent work by Sadler, Draijer [ 89 ] suggests that 400 mg daily CF supplementation for seven days improves oxygen uptake during moderate-intensity exercise, but this benefit was not observed during high-intensity exercise.…”

“…The mechanism for this increase may be due to CF decreasing ROS production and thereby attenuating fatigue [ 41 , 42 ]. An acute dosing strategy with higher flavanol products did not elicit any cycling performance benefit, only inducing slightly higher nitric oxide levels during exercise, which could aid muscle blood flow [ 86 ].…”