Caffeine increases performance and leads to a cardioprotective effect during intense exercise in cyclists

Abstract

The present study was designed to investigate the effects of different caffeine dietary strategies to compare the impact on athletic performance and cardiac autonomic response. The order of the supplementation was randomly assigned: placebo(4-day)-placebo(acute)/PP, placebo(4-day)-caffeine(acute)/PC and caffeine(4-day)-caffeine(acute)/CC. Fourteen male recreationally-trained cyclists ingested capsules containing either placebo or caffeine (6 mg kg−1) for 4 days. On day 5 (acute), capsules containing placebo or caffeine (6 mg kg−1) were ingested 60 min before completing a 16 km time-trial (simulated cycling). CC and PC showed improvements in time (CC vs PP, Δ − 39.3 s and PC vs PP, Δ − 43.4 s; P = 0.00; ƞ2 = 0.33) and in output power (CC vs PP, Δ 5.55 w and PC vs PP, Δ 6.17 w; P = 0.00; ƞ2 = 0.30). At the final of the time-trial, CC and PC exhibited greater parasympathetic modulation (vagal tone) when compared to the PP condition (P < 0.00; ƞ2 = 0.92). Our study provided evidence that acute caffeine intake (6 mg∙kg−1) increased performance (time-trial) and demonstrated a relevant cardioprotective effect, through increased vagal tone.

Does Caffeine Supplementation Associated with Paralympic Powerlifting Training Interfere with Hemodynamic Indicators?

“…However, the half-life of caffeine varies between 2 and 10 h [ 21 , 24 , 29 , 40 ], which could explain the reduction in absolute SBP values with CA only 24 h after exercise. This effect can also be explained by changes in autonomic modulation [ 5 , 23 , 41 ]. Previous findings showed an increase in parasympathetic modulation after the consumption of 3 to 6 mg kg of caffeine, in addition to suggesting that caffeine dosage and parasympathetic reactivity are not linear [ 23 , 41 ].…”

“…As exclusion criteria, the fact that they were using some type of illicit ergogenic resource and had some type of symptomatic cardiorespiratory or cardiac disease was considered. Female athletes did not participate, because in women, alterations in CA metabolism can occur, which may lead to a reduction in the ergogenic effects of CA, due to the interaction of the supplement with female sex hormones [ 19 ], especially in women who use contraceptives [ 23 ]. The athletes participated in the study voluntarily and signed an informed consent form, under the resolution 466/2012 of the National Research Ethics Commission—CONEP, of the National Health Council, following the ethical principles expressed in the Declaration of Helsinki (1964, reformulated in 1975, 1983, 1989, 1996, 2000, 2008, and 2013) from the World Medical Association.…”

“…Moreover, following the removal of CA from the World Anti-Doping Agency’s list of prohibited supplements, consumption of CA in competitions has increased significantly from 2004 to 2015 [ 19 ]. However, it can interfere with BP and HR [ 21 , 22 , 23 ], raising concerns about its use, since people with lower limb deficiencies tend to have more risk factors for arterial hypertension [ 15 ]. This is especially relevant for Paralympic athletes, as 12% of them have cardiovascular abnormalities and 2% have a high risk of sudden cardiac death in addition to other heart diseases [ 4 ].…”

“…This is especially relevant for Paralympic athletes, as 12% of them have cardiovascular abnormalities and 2% have a high risk of sudden cardiac death in addition to other heart diseases [ 4 ]. CA is an antagonist of adenosine A1 and A2 receptors, capable of crossing the blood–brain barrier and, at the level of the central nervous system (CNS), it stimulates the release of noradrenaline, dopamine, acetylcholine, and serotonin, in addition to stimulating muscle contraction and lipolysis [ 21 , 22 , 23 ]. Regarding the dose, low doses of CA ≤ 3 mg/kg of body weight have been suggested to be more effective in long-term exercise, while higher doses of 5–9 mg/kg of body weight may be more effective for a healing effect.…”

Anthocyanin-Rich Supplementation: Emerging Evidence of Strong Potential for Sport and Exercise Nutrition

“…Most sport and exercise performance supplementation studies employ the gold standard randomized, double-blind, placebo-controlled cross-over design, with a few exceptions of studies with testing more than once in the placebo and supplementation condition [e.g., caffeine: ( 32 ), sodium bicarbonate: ( 33 , 34 )]. Individual responses for physiological and performance responses are commonly ignored [e.g., beetroot: ( 35 ), caffeine: ( 36 )]. With respect to anthocyanin intake, the landmark study by Czank et al ( 37 ) on the absorption, distribution, metabolism and elimination of isotopically labeled cyanidin-3- O -glucoside (6,8,10,3′,5′- 13 C 5 -C3G) noted the interindividual variability in total 13 C recovery from urine, fecal, breath and blood samples with a range from 15.1 to 99.3% over a 2-day period.…”