Beneficial Physiological Effects With Blackcurrant Intake in Endurance Athletes

Abstract

19Blackcurrant contains anthocyanins, known to influence vasorelaxation and peripheral blood 20 flow. We examined the effects of 7 days intake of Sujon New Zealand blackcurrant powder 21 (6g/day) on the lactate curve, maximum oxygen uptake, and cardiovascular responses at rest and 22 during cycling. Thirteen trained triathletes with >3 yrs experience (8 men, age: 38±8 yrs, body 23As accepted for publication, http://journals.humankinetics.com/ijsnem As accepted for publication, http://journals.humankinetics.com/ijsnem mass: 71±9 kg, BF%: 19±5%, mean±SD) performed two incremental cycling protocols with 24 recording of physiological and cardiovascular responses (Portapres® Model 2). Cardiovascular 25 function was also measured in rest. Experimental design was double-blind, placebo-controlled, 26 randomized and cross-over (wash-out 4 wks). Data was analysed with two-tailed t-tests and 2-27 way ANOVA and significance accepted at p<0.05. Plasma lactate was lower at 40%, 50%, 60% 28 and 70% of maximum power by 27%, 22%, 17% and 13%. Intensity at 4 mmol•L -1 OBLA was 29 6% higher with blackcurrant without effect on heart rate and oxygen uptake. Maximum values of 30 oxygen uptake, heart rate and power were not affected by blackcurrant, but obtained with 14% 31 lower lactate. In rest, blackcurrant increased stroke volume and cardiac output by 25% and 26%, 32 and decreased total peripheral resistance by 16%, with no changes in blood pressure and heart 33 rate. Cardiovascular responses during exercise at 40%, 50%, 60%, 70% and 80% intensity were 34 not affected. Sujon New Zealand blackcurrant powder affects lactate production and/or clearance 35 during exercise. Sujon New Zealand blackcurrant powder affects physiological and 36 cardiovascular responses in rest and during exercise that may have implications for exercise 37 performance. 38 39

Blackcurrant Alters Physiological Responses and Femoral Artery Diameter during Sustained Isometric Contraction

“…From the Fick equation [36], an increase in O 2 delivery (i.e., from an increase in cardiac output) would be expected to enable an increased uptake of O 2 . However, Willems et al [2] and Cook et al [4] did not observe any alteration in oxygen uptake during exercise following NZBC, therefore this warrants further investigation. In addition, the present study did not measure the pulmonary oxygen uptake response to the isometric contraction; therefore, this mechanism is speculative.…”

“…Each capsule of 300 mg contains 105 mg of anthocyanins, i.e., 35%–50% delphinidin-3-rutinoside, 5%–20% delphinidin-3-glucoside, 30%–45% cyanidin-3-rutinoside, and 3%–10% cyanidin-3-glucoside with remaining content mainly natural plant sugars. The dose used was established from a previous study in which a dose-response relationship in cardiovascular responses was observed in trained cyclists [2]. Optimal dosing strategy for New Zealand blackcurrant extract is not known.…”

“…Cohen [23] described an effect size of <0.2 as a trivial, 0.2–0.39 as a small, 0.4–0.69 as a moderate and ≥0.7 as a large magnitude of change. From the 15% change in cardiac output following 600 mg∙day −1 of NZBC extract in Cook et al [2], an a-priori power analysis indicated a sample size of 13 would allow a detection of a 15% increase in cardiac output with a high statistical power (1−β = 0.95: 0.05 = α level). All data are reported as mean ± SD and significance was accepted at p < 0.05.…”

“…New Zealand blackcurrant (NZBC) altered cardiovascular function in rest by increased cardiac output [2,3], and improved cycling endurance [4] and repeated high-intensity running performance [5]. However, the mechanisms for the ergogenic effects of New Zealand blackcurrant are unknown.…”

Selected In-Season Nutritional Strategies to Enhance Recovery for Team Sport Athletes: A Practical Overview

“…Ammar et al [131] showed that pomegranate juice lowered the perception of knee extensor soreness and attenuated the acute rise in specific markers of tissue damage [e.g., creatine kinase (CK), lactate dehydrogenase] 3 min after Olympic weight-lifting movements, and improved the recovery kinetics of these same markers 48 h after exercise. Blackcurrant has been studied for its effects on exercise performance [135, 136], substrate oxidation [137], and physiological measures, such as blood lactate level [135, 136, 138]. Only one study has tested the effects of BC on exercise-induced muscle damage, subjective ratings of muscle soreness, and inflammation post-exercise [133].…”