This happens quite often in the world of Nutrition as well as Sport that a word gets thrown around without complete understanding of what that word or term is. Today that word is Antioxidant. Without diving too far into the chemistry and biochemistry of how antioxidants work, antioxidants protect against free radicals or reactive oxygen species (ROS). The chemical structure of free radicals allow them to go around the body ‘stealing’ electrons from healthy cells in the body causing damage. Antioxidants go around the body finding these free radicals and donate electrons to the free radicals to protect the body. The body begins to get damaged when the free radicals overwhelm the antioxidant defenses.
In the world of athletics and sport, exercise can increase the presence of free radicals by 10-15% then a normal person. This increase in free radical production may result in increased fatigue, muscle damage and reduced immune function. In response to this it’s fairly logical to increase intake of foods with a higher amount of antioxidants such as Vitamin C, Vitamin E, Carotenoids and Flavonoids (colour pigments and metabolites from vegetables, respectively), but does this actually help? And does this additional supplementation improve athletic performance?
In a 2005 study by Watson et al. it was found that in a group eating a high antioxidant diet vs. one that was eating an antioxidant deprived diet that oxidative stress was higher in the restricted group. However, in another study by Watson et al. supplementing athletes with Vitamin E actually increased oxidative stress! In another study by Peternelj & Coombes (2011), the researchers found loading cells with antioxidants produced a ‘blunting’ of the benefits of exercise and interfered with the beneficial aspects of ROS, which include vasodilation and insulin signaling.
A study by Clarkson and Thompson (2000) and Paulsen et al (2014) showed that additional antioxidants were needed to prevent oxidative stress in athletes but did not find any positive impact on athletic performance. They also found that exercise training appears to reduce the oxidative stress of exercise in trained athletes when compared to the general population. This finding was also supported by Draeger et al. (2014). Finally, Lamina et al. (2013) and Marin et al. (2013) found that overtraining causes increase oxidative stress.
It is recommended by researchers that athletes eat a minimum of 2-3 servings of fruit and 4-5 servings of vegetables per day to ensure a diet high in antioxidants. In all cases researchers recommended that antioxidants be consumed through the diet rather then through supplementation. In fact antioxidants from whole foods resulted in the optimal ratio in the body vs supplementary sources of antioxidants. So yes, athletes do require more antioxidants to adapt to the stressors of training but they should be consumed through whole foods as opposed to supplements. You may be asking at this point, what foods have antioxidants in them? Well the best food sources of antioxidants include wheat, barley, sprouts, dark green vegetables, blueberries, blackberries, strawberries and any food high in Vitamin E, Vitamin C, Beta-Carotene, Selenium and Flavonoids.
The bottom line? Eat your fruits and vegetables! Choose from a variety of fruits and vegetables while looking at the entire color spectrum. Different colors indicate different nutrients, vitamins and minerals, so eat a large variety to get all your bases covered. Put down that bottle of mega-dosed vitamins that aren’t doing you any good. Eat more fruits and vegetables and let your body optimize the amount of antioxidants it needs as opposed to doing a supplemental blitzkrieg! And in more severe cases of fatigue, muscle damage or impaired immune function go see a Sports Dietitian to help best optimize your nutritional intake for athletic performance and optimal health!
Ben Sit, RD, Sports Dietitian
I am a Registered Dietitian and Sports Dietitian. I received my undergraduate degree from Ryerson University’s School of Nutrition and graduated my Dietetic Internship from the Sunnybrook Dietetics Internship Program in 2010. In 2013, I received a Sports Dietitian Certificate from the Sports Dietitians of Australia and am currently pursuing Ryerson’s Physical Activity Assessment and Promotion certificate program, a personal trainer’s certificate and the International Olympic Committee’s Sports Nutrition Diploma.
I am also an athlete and when I’m not training for my next marathon, bike race, lifting weights or doing cross-fit workouts I’m busy cooking up a storm developing recipes for athletes. I specialize in endurance events and weight lifting but am more than qualified to work with any sport and medical conditions. I also trained as a Chef and a Pastry Chef in a number of Restaurants and Hotels across Toronto before combining the culinary world with dietetics and sport. Using all my combined knowledge I’m currently in the process of writing two cookbooks targeted towards athletes and the general public looking to live a healthier and more flavourful life. One of my biggest passions in life aside from Physical Activity, Nutrition and Food is travel. In fact, I will continue to travel the world, studying different cultures, cuisines and cooking styles in order to best serve my clients.
I believe that comfort is the greatest enemy of growth. My nutritional interventions will only work if you work together with me to defeat the part of you that has become content on your current lifestyle. Personal and emotional growth is what is needed in order for you to meet your own personal goals. After all, you’re driving the car to get to the destination; I give the directions on how to get there quickly, effectively and safely.
I also believe that true health cannot be attained by looking at any one particular aspect of the magnitude of things that affect our health, which is why I’m a proud member of the BBD team. At BBD there is recognition that true health and attaining health related goals involves a multi angle approach to the individual. From personalized nutritional goals to personalized training regimens, BBD’s team will tailor interventions to focus on the individual to not only reach your fitness goals, but to encourage and build a sustainable healthy lifestyle.