Effects of Different Doses of Caffeinated Coffee on Muscular Endurance, Cognitive Performance, and Cardiac Autonomic Modulation in Caffeine Naive Female Athletes

Abstract

Caffeine is widely consumed among elite athletes for its well-known ergogenic properties, and its ability to increase exercise performance. However, studies to date have predominantly focused on the anhydrous form of caffeine in male participants. The aim of the study was to investigate the effect of caffeinated coffee ingestion on lower-upper body muscular endurance, cognitive performance, and heart rate variability (HRV) in female athletes. A total of 17 participants (mean ± standard deviation (SD): age = 23 ± 2 years, body mass = 64 ± 4 kg, height = 168 ± 3 cm) in a randomized cross-over design completed three testing sessions, following the ingestion of 3 mg/kg/bm of caffeine (3COF), 6 mg/kg/bm of caffeine (6COF) provided from coffee or decaffeinated coffee (PLA) in 600 mL of hot water. The testing results included: (1) repetition number for muscular endurance performance; (2): reaction time and response accuracy for cognitive performance; (3): HRV parameters, such as standard deviation of normal-to-normal (NN) intervals (SDNN), standard deviation of successive differences (SDSD), root mean square of successive differences (RMSSD), total power (TP), the ratio of low- and high-frequency powers (LF/HF), high-frequency power (HF), normalized HF (HFnu), low-frequency power (LF), and normalized LF (LFnu). A one-way repeated measures ANOVA revealed that 3COF (p = 0.024) and 6COF (p = 0.036) improved lower body muscular endurance in the first set as well as cognitive performance (p = 0.025, p = 0.035 in the post-test, respectively) compared to PLA. However, no differences were detected between trials for upper body muscular endurance (p = 0.07). Lastly, all HRV parameters did not change between trials (p > 0.05). In conclusion, ingesting caffeinated coffee improved lower body muscular endurance and cognitive performance, while not adversely affecting cardiac autonomic function.

Does Acute Caffeine Supplementation Improve Physical Performance in Female Team-Sport Athletes? Evidence from a Systematic Review and Meta-Analysis

“…Of this sample, 50 participants were basketball players [14,35,38,43], 40 were volleyball players [30,33,41], 37 were soccer players [29,40], 32 were rugby players [28,31] and 15 were handball players [32]. The rest of the studies used a sample of mixed TSA including basketball, volleyball, handball, soccer, rugby, softball, hockey and netball players [26,27,34,[44][45][46].…”

“…Caffeine doses ranged from 1.3 mg/kg to 6 mg/kg, mainly ingested through: capsules: nine studies [14,26,27,32,34,38,[43][44][45], powders: five studies [28][29][30][31]35], energy drinks: two studies [40,41], power bars: one study [33] or coffee [46].…”

“…From 2015, some studies reported the menstrual cycle phase while others were even more strict and performed the evaluations when participants were in a specific phase. For example, Buck et al [26] standardized the assessments with the protocol of starting in the first three days after the last menstruation (follicular phase), Chen et al [34] instructed athletes to participate during their early follicular phase and Puente et al [14], Stojanovic et al [38] and Karayigit et al [46] completed their assessments during the luteal phase. Specific phases and the use of oral contraceptives are specified in Table 1.…”

The Dose-Effects of Caffeine on Lower Body Maximal Strength, Muscular Endurance, and Rating of Perceived Exertion in Strength-Trained Females

“…However, an investigation did explore the use of caffeine during the early follicular phase [21], which was selected due to this phase resulting in the lowest variability in ovarian hormones [37] and significant improvements were observed in both strength and endurance. The lack of previous control investigations [23,38,39] may have led to varying rates of metabolism at different points throughout the menstrual cycle, potentially confounding results. In contrast, as stated the current investigation used strength-trained females who were using hormonal contraception, which may have alleviated the chance of individual hormonal fluctuations influencing responses to caffeine [21].…”

High Dose of Caffeine Mouth Rinse Increases Resistance Training Performance in Men

“…Caffeine is one of the most used nutritional ergogenic aid by athletes [1] and considered effective in improving cardiorespiratory endurance [2], movement velocity [3], power [4] and muscular endurance during resistance exercises [5,6]. The exact mechanisms, likely to be multifactorial, by which it shows benefits in neurotransmission, perceived exertion and arousal, are mediated by adenosine receptor (A 1 , A 2A , A 2B ) antagonism [7].…”