‘Antioxidants’ is a mysterious category of supplements commonly fed to horses despite a general lack of understanding by the average horse person as to what they actually do. Most of us would suggest that antioxidants just make our exercising horses appear to ‘do better’ or ‘feel better’ without really being able to say with any certainty what aspect of health or performance is actually improved.
Essentially, you can think of antioxidants as a biological vacuum cleaner. During times of physiological stress, such as that created by exercise, the increased consumption of oxygen leads to production of reactive oxygen species (ROS) which can break down proteins and impair function of tissues. The body launches natural antioxidant defenses against ROS, but when lots are being produced (such as during exercise), consumption of oxygen and consequent production of ROS can ‒ and frequently does ‒ exceed the body’s ability to clean up the ROS mess, contributing to exercise intolerance and fatigue.
Dietary antioxidants help maintain a balance between oxygen consumption and persistence of ROS in exercising tissues. Part of the contribution of ROS to the development of fatigue during exercise is the ROS-caused ‘stiffening’ of red cell membranes. Red cells are the delivery wagon for oxygen to exercising tissue, and in order for them to effectively to their job, red cell membranes need to stay as flexible as possible so they can move through tiny capillary beds, deliver their oxygen cargo, and take away carbon dioxide waste.
The research paper Effects of exercise and oral antioxidant supplementation enriched in (n-3) fatty acids on blood oxidant markers and erythrocyte membrane fluidity in horses (De Moffarts B, Portier K, Kirschvink N, et al.) reports that supplementation of exercising horses with 100 mL/day of an antioxidant supplement containing 50 mL fish oil, 5000 mg vitamin E, and 5000 mg copper orotate for three weeks reduces the stiffening effects of exercise on red cell membranes and improves the oxidative balance.
What does this mean for your horse?
While the general health and performance benefits of antioxidants have been recognized for a long time, this study provides a tangible example of the direct effects of omega-3 fatty acids and other antioxidants.
In conclusion, dietary antioxidants can be an effective way to protect red cell membranes from ROS, and delay the onset of fatigue in exercising horses. Herbs for Horses manufactures an ANTIOXIDANT blend containing seven well-researched plant antioxidants.