08/03/11: A novel polyphenol blend for peak athletic performance

A novel polyphenol blend for peak athletic performance

By Kelly C. Heim, Ph.D.

During intense exercise, muscles require highly efficient and consistent delivery of fuel substrates with concurrent removal of metabolic byproducts. This dynamic exchange is made possible by elevated blood flow through the intramuscular vasculature. Blood vessel diameter is a major determinant of nutrient delivery and lactate clearance. Accordingly, natural compounds that facilitate dilation of blood vessels during exercise are associated with enhanced high-intensity athletic performance.1

Polyphenol-rich extracts of cranberry, grape seed and green tea have long been known to support vascular endothelial function. Recent clinical research indicates that cranberry and grape polyphenols support peak athletic performance by augmenting blood flow. Rich in oligomeric flavonoids known as proanthocyanidins, cranberry and grape seed promote the activity of nitric oxide synthase (NOS), the enzyme that generates nitric oxide, a powerful endogenous regulator of endothelial tone.2,3

An ongoing research collaboration with the Institute of Nutraceuticals and Functional Foods (INAF) and Laval University in Quebec, Canada has led to the development and clinical validation of CranLoad™, a novel, proprietary formula of proanthocyanidin-rich cranberry and grape seed extracts. In a pilot trial of elite athletes, consumption of a CranLoad™ containing beverage increased flow-mediated dilation (FMD), an indicator of blood flow measured by brachial artery diameter. The increase in FMD was significant within 30 minutes and remained elevated for 2 hours (Fig. 1). The peak increase in brachial artery diameter was similar to published values for high doses of l-Arginine ranging from 3-21 grams. This data suggests that CranLoad™ and l-Arginine produce similar effects on blood flow.4

Graph FMD Cranloadsmlr .2

Figure 1. Flow-mediated dilation (FMD) variation from baseline after intake of the polyphenol-rich drink and placebo; *P<0.05 versus baseline and placebo at specified time points. The insert presents the area under the curve (AUC) of the change in FMD over time above baseline (time 0) values. The Y axis is in % min*.

Optimizing circulation facilitates the removal of lactate, supporting endurance and recovery. The effects of CranLoad™ on lactate dynamics was evaluated in a double-blind, placebo-controlled, pilot trial. Elite, high-profile athletes consumed CranLoad™ followed by a 3 km stationary cycling time trial. A significant decrease in blood lactate was evident relative to placebo. These findings are consistent with the well-established correlations between blood flow, lactate and high-intensity athletic performance.

While proanthocyanidins from cranberry and grape seed are complex oligomers of polyphenols, green tea is a rich source of low-molecular weight polyphenols that support energy metabolism, particularly fat utilization.5 Green tea also supports mental focus by virtue of naturally occurring caffeine, one of the most extensively researched natural agents in sports nutrition. As caffeine supports endurance and muscular force, it promotes both aerobic and anaerobic performance.6-8

CranLoad™ Sport delivers a powerful combination of CranLoad™ and naturally-occurring caffeine from green tea. This strategic combination is provided in a base of medium chain triglycerides (MCTs), delivered in a unique, bioavailable, liquid-filled Caplique® Capsule. The combined properties of polyphenols and caffeine make this innovative formula applicable across a broad range of sports, particularly those requiring high-intensity training.


  1. Bailey SJ, Winyard PG, Vanhatalo A, Blackwell JR, DiMenna FJ, Wilkerson DP, Jones AM. Acute L-arginine supplementation reduces the O2 cost of moderate-intensity exercise and enhances high-intensity exercise tolerance. J Appl Physiol. 2010 Nov;109(5):1394-403.
  2. Caton PW et al. Regulation of vascular endothelial function by procyanidin-rich foods and beverages. J Agric Food Chem. 2010 Apr 14;58(7):4008-13.
  3. Feng Z, Wei RB, Hong Q, Cui SY, Chen XM. Grape seed extract enhances eNOS expression and NO production through regulating calcium-mediated AKT phosphorylation in H2O2-treated endothelium. Cell Biol Int. 2010 Oct 1;34(10):1055-61.
  4. Bai Y, Sun L, Yang T, Sun K, Chen J, Hui R. Increase in fasting vascular endothelial function after short-term oral L-arginine is effective when baseline flow-mediated dilation is low: a meta-analysis of randomized controlled trials. Am J Clin Nutr. 2009 Jan;89(1):77-84.
  5. Murase T, Haramizu S, Shimotoyodome A, Tokimitsu I, Hase T. Green tea extract improves running endurance in mice by stimulating lipid utilization during exercise. Am J Physiol Regul Integr Comp Physiol. 2006 Jun;290(6):R1550-6.
  6. Tarnopolsky M, Cupido C. Caffeine potentiates low frequency skeletal muscle force in habitual and nonhabitual caffeine consumers. J Appl Physiol. 2000 Nov;89(5):1719-24.
  7. Gliottoni RC, Meyers JR, Arngrimsson SA, Broglio SP, Motl RW. Effect of caffeine on quadriceps muscle pain during acute cycling exercise in low versus high caffeine consumers. Int J Sport Nutr Exerc Metab. 2009 Apr;19(2):150-61.
  8. Hadjicharalambous M, Georgiades E, Kilduff LP, Turner AP, Tsofliou F, Pitsiladis YP. Influence of caffeine on perception of effort, metabolism and exercise performance following a high-fat meal. J Sports Sci. 2006 Aug;24(8):875-87.


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