Appalachian State

Exercise and Polyphenols- Absorption and Afterburn Effect First to be Found in Human Study

September 03, 2013


For Immediate Release


Phyllis Beaver
Marketing Director
NC Research Campus

Justin Moore
Extension Communications
NC State University
Plants for Human Health Institute

Jane Nicholson
Director of University News
Appalachian State University
Read the full story.


(NC Research Campus, Kannapolis, NC- September 3, 2013) New findings from a collaborative study by Appalachian State University, Dole Food Company and NC State University show some of the first evidence in a human clinical trial of an alternate route of polyphenoic absorption via the colon and a polyphenolic metabolic afterburn following exercise.

Polyphenols are a class of bioactive compounds in fruits and vegetables that are linked to health benefits such as lowering blood pressure and blood glucose, reducing inflammation and fighting off the damaging effects of free radicals. They were thought to enter the blood stream through the small intestine.

This study is one of the first human trials to provide evidence that polyphenols travel to the colon and are released into the blood in elevated levels, which was identified by a polyphenolic signature in the blood that was characteristic of gut microbial metabolism. The study also showed that polyphenolic metabolism was accelerated for up to 14 hours after exercise showing a substantial afterburn effect.

Study authors David Nieman, DrPH, FACSM, director of the Appalachian State University Human Performance Laboratory; Mary Ann Lila, PhD, director of the North Carolina State University Plants for Human Health Institute; and Nicholas Gillitt, PhD, director of nutrition research for Dole Food Company, published their results in the paper Influence of a Polyphenol-Enriched Protein Powder on Exercise-Induced Inflammation and Oxidative Stress in Athletes: A Randomized Trial Using a Metabolomics Approach on PlosOne on August 15, 2013.


Importance of the Findings
“Burn fat while you sleep is a great message,” emphasized Lila. “We showed that the metabolism is stimulated by exercise, but we saw fatty acid oxidation and ketogenesis with more ketones at 14 hours post exercise in the treatment group. The placebo group went back to normal levels.”  Ketogenesis is the production of ketones that result from the breakdown of fatty acids into energy.

The finding is relevant, Nieman added, because it points to increased gut permeability as another important benefit of exercise. “If you are willing to exercise hard enough to sweat, gut permeability increases, and you get more of these beneficial compounds coming back into your body.”

Gillitt summarized, “It is useful to show in human clinical trials that when you eat fruits and vegetables, these compounds can flood into the system, even if it is not by the classic way everyone thought they did. We have already shown the carbohydrates in bananas provide a good source of energy during exercise. This study shows the polyphenols found in fruits and vegetables could also be helpful to athletes who experience high levels of oxidative stress and inflammation.”


About the Study
The collaborative study tested polyphenol supplementation as a countermeasure to inflammation and oxidative stress. Long-distance runners were given either a soy protein complex infused with polyphenols from blueberries and green tea or just the protein complex. The runners ingested the soy protein complex for two weeks and during three days of running for two-and-a-half hours each day. Each dose was the equivalent of consuming three cups of blueberries and just over a cup of brewed green tea.

These NC Research Campus scientists are planning additional collaborative studies to build on their findings in order to better understand the physiological mechanisms at play and the potential applications for athletes and consumers.


About the NC Research Campus
The NC Research Campus (NCRC) is home to corporate, academic and healthcare partners focused on advancing science at the intersection of human health, agriculture and nutrition. The NCRC is located on a 350-acre campus in Kannapolis, NC, just north of Charlotte, and has over a million square feet of lab and office space under management that includes five buildings.
The Appalachian State University Human Performance Laboratory at the NCRC is a national leader in the area of nutrition and exercise immunology. They work with trained and amateur athletes, corporate collaborators and sponsors as well as community participants to investigate the influence of plant molecules on age-related loss of muscle mass (sarcopenia), muscle mitochondrial biogenesis and exercise-induced changes in immune function, oxidative stress and inflammation.
The North Carolina State University Plants for Human Health Institute integrates research in metabolomics, biochemistry, pharmacogenomics, plant breeding and post-harvest physiology to improve the health-enhancing properties of food crops to decrease the incidence of chronic disease and to increase farm sustainability and profitability.
The Dole Nutrition Research Laboratory identifies and quantifies phytochemicals in the company’s fruits and vegetable portfolio in order to help prevent the development of many common diseases such as heart disease, cancer and diabetes. The Dole laboratory also works on how to enhance the nutritional benefits of its products by supporting the research requests of the company’s divisions and collaborating with NCRC partners.
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