Involvement of Cardiorespiratory Capacity on the Acute Effects of Caffeine on Autonomic Recovery

Abstract

Background and objectives: As a result of ergogenic properties, caffeine has been increasingly taken prior to physical exercise, yet its effects on post-exercise recovery, considering the differences in the cardiorespiratory capacity of the individuals, has not yet been studied or fully elucidated. Optimizing the post-exercise recovery can convey advantages to physical activity practitioners. We evaluated the acute effects of caffeine on heart rate (HR) autonomic control recovery following moderate aerobic exercise in males with different cardiorespiratory capacities. Materials and Methods: We split young adult men into two groups based on their various oxygen consumption peaks (VO2 peak): (1) Higher VO2 (HO): Sixteen volunteers, peak VO2 > 42.46 mL/kg/min and (2) Low VO2 (LO): Sixteen individuals, VO2 < 42.46 mL/kg/min). The volunteers were submitted to placebo and caffeine protocols, which entailed 300 mg of caffeine or placebo (starch) in capsules, followed by 15 min of rest, 30 min of moderate exercise on a treadmill at 60% of the VO2 peak, followed by 60 min of supine recovery. Heart rate variability (HRV) indexes in the time and frequency domains were examined. Results: Effect of time for RMSSD (square root of the average of the square of the differences between normal adjacent RR intervals) and SDNN (standard deviation of all normal RR intervals recorded in a time interval) was achieved (p < 0.001). Significant adjustments were observed (rest versus recovery) at the 0 to 5th min of recovery from exercise for the LO during the placebo protocol and at the 5th at 10th min of recovery for the caffeine protocol. For the HO in both procedures we found significant alterations only at the 0 to 5th min of recovery. Conclusion: Caffeine delayed parasympathetic recovery from exercise in individuals with lower cardiorespiratory capacity.

Avocado (Persea americana) pulp improves cardiovascular and autonomic recovery following submaximal running: a crossover, randomized, double-blind and placebo-controlled trial

“…When the subjects were ingested avocado pulp, SBP recovered after 2 min following exercise and HR returned after 10 min after exercise termination, while in the placebo protocol, SBP recovered after 3 min following exercise cessation and HR recovered after 20 min of recovery. The abovementioned findings are in accordance with Dzeufiet et al 41 , who studied animals treated with aqueous avocado extract (50, 100 and 150 mg/kg) for five weeks. Their results confirmed that aqueous avocado extract dose-dependently reduced HR and blood pressure of ethanol-sucrose induced hypertensive rats.…”

“…Recent studies have intended to evaluate the cardioprotective effect of avocado 19,41,42 . The aforesaid references demonstrated the valuable influences of avocado fruit, avocado oil or avocado extract.…”

Lower Systolic Blood Pressure in Normotensive Subjects is Related to Better Autonomic Recovery Following Exercise

“…After exercise cessation, a temporary decline in SBP below pre-exercise levels is as a result of peripheral vasodilation 32 . www.nature.com/scientificreports www.nature.com/scientificreports/ HR during exercise is controlled by neural and peripheral mechanisms (mechanoreceptors and/or metaboreceptors) 29,30 . Muscle metaboreceptors are activated in response to accumulation of metabolites (H+, K+, adenosine, lactate), decreasing baroreflex sensitivity [33][34][35][36] .…”

“…The HR, RR, SBP, and DBP data were logged at the 15 th minute of the initial rest and at 1 st , 3 rd , 5 th , 7 th , 10 th , 20 th , 30 th , 40 th , 50 th and 60 th minutes after exercise (Fig. 2) [27][28][29] .…”

The effects of varying doses of caffeine on cardiac parasympathetic reactivation following an acute bout of anaerobic exercise in recreational athletes

“…However, research ndings are mixed, with some studies showing that 300-400 mg of caffeine delays post-exercise parasympathetic reactivation (12,14,15), while others have found no effect from caffeine at doses associated with <3 mg•kg -1 body mass (16,17). While it is di cult to compare and contrast results across studies, these inconsistent ndings may be related to the caffeine dosage used, which warrants further investigation within athletic populations.…”