Medium Chain Triglycerides - A runners secret fuel supply

Myprotein.com Sports Scientist Ross Edgley explores why more and more runners are starting to supplement their diet with medium chain triglycerides (MCT’s) and what benefits they could provide for you

Whilst carbohydrates will undoubtedly (and quite rightly) remain the primary choice of fuel for runners because of their ability to replenish muscle glycogen levels, improve endurance and enhance sports performance, recent studies show medium chain triglycerides could provide an effective ‘seconday’ source.

Firstly a little about the history of medium chain triglycerides; they were formulated back in the 1950’s as a special kind of fatty acid that would serve as a calorie source for people with the inability to digest fats or who need to gain weight quickly, such as those suffering from cancer and other diseases. They are absorbed more quickly than their chemical cousins, long-chain triglycerides, because they're shorter and more soluble in water. This makes it possible for medium chain triglycerides to pass directly from the intestines into the bloodstream (quite similar to how carbohydrates are used) unlike how most fatty acids must pass from the intestines into the lymphatic system before they can enter the bloodstream. It’s believed this unique quality of medium chain triglycerides is responsible for its energy boosting and performance enhancing properties and why it acts more like a fuel like carbohydrates than a fat.

Secondly, and perhaps more importantly for runners looking to keep their body fat low, MCT’s have been shown to have fat loss qualities as well as being a source of fuel. Firstly, as previously mentioned, because of the way they are transported directly to the liver and used for energy, only 1-2% of them are stored as fat, despite one gram of MCT’s providing 8 calories according to a study conducted by Bach, A.C., Ingenbleek, Y., & Frey, A (1996,) - this is compared to protein and carbohydrates that possess 4 calories per gram.

This essentially makes them a very effective energy supply that doesn’t increase your body fat percentage (something excess carbohydrates may.) Furthermore, experts believe MCT’s are less likely to be stored as fat because they boost your metabolic rate. Papamandjaris, A.A et al (2000) claims that 400 calories of MCT’s increases the metabolic rate for at least six hours after a meal to a greater extent than other types of fat. Plus, according to Seaton, T.B et all (1986) in a study published in the American Journal of Clinical Nutrition, MCTs also increase the rate at which other fats in the diet are burned for energy.

Lastly because of the speed at which MCT’s are used as fuel, some experts believe they have muscle glycogen sparing properties i.e. your body uses the MCT’s as fuel whilst sparring muscle glycogen for later in a race. In fact in one study conducted at the University of Cape Town Medical School it was discovered medium chain triglyceride ingestion increased free fatty acid concentration, reduced carbohydrate oxidation and spared muscle glycogen stores, all of which resulted in the improved performance of the 6 endurance-trained cyclists that completed a simulated 40-km time trial during the study.

So how much do you need in your diet before you start to see an improvement in your running times?

Well medium chain triglycerides form part of your daily intake of fat i.e. they are simply primary macro nutrients that your body needs daily. Studies tend to vary quite a lot between 10-15 grams, but some research seems to suggest runners covering long distances, and that require the additional calories, may need as much as 50 grams of medium chain triglycerides.

Also very similar to carbohydrates, they are best consumed before training/competition to provide the necessary fuel to complete the run. Now you can get medium chain triglycerides in their purest form by supplementing your diet with MCT Powder (£14.99 for 250g from Myprotein.com) in which case adding 2 teaspoons (10 grams) to your water or juice with your breakfast would be ideal.

Alternatively some athletes prefer to consume a natural source of medium chain triglycerides which can be found in Coconut Oil (Coconpure is £8.99 for 460ml from Myprotein.com.) Coconut Oil can be easily incorporated into the diet and can be used to cook with, fry, bake and even make smoothies or to really give you the best possible start to the day, mix it in with a boil of porridge and honey. Whilst there isn’t really a recommended dosage of coconut oil (since it can be used instead of cooking oil) experts recommend up to 4 tablespoons per day.

References:

• C. G. Van Zyl, E. V. Lambert, J. A. Hawley, T. D. Noakes, S. C. Dennis (1996) 'Effects of medium-chain triglyceride ingestion on fuel metabolism and cycling performance’ The American Physiological Society
• Marie-Pierre St-Onge, Robert Ross, William D. Parsons and Peter J.H. Jones (2003) ‘Medium-Chain Triglycerides Increase Energy Expenditure and Decrease Adiposity in Overweight Men’ Obesity Research (2003) 11, 395–402
• N Baba, EF Bracco and SA Hashim (1982) ‘Enhanced thermogenesis and diminished deposition of fat in response to overfeeding with diet containing medium chain triglyceride’ American Journal of Clinical Nutrition, Vol 35, 678-682
• Ron J Maughan (2005) ‘Role of micronutrients in sport and physical activity’ Department of Biomedical Sciences, University Medical School, Foresterhill, Aberdeen
• Theodore B. Van Itallie, M.D. Leonardo Sinisterra, M.D. Fredrick J. Stare, M.D. (1997) ‘Nutrition and Athletic Performance’ The Journal of the American Medical Association
• Ron J Maughan (2007) ‘The athlete’s diet: nutritional goals and dietary strategies’ Proceedings of the Nutrition Society
• Blixt, G (1965) A Study on the relation between total calories and single nutrients for athletes’ Sociologica et Medica Upsallieusis
• Bach, A.C., Ingenbleek, Y., & Frey, A. (1996). The usefulness of dietary medium-chain triglycerides in body weight control: fact or fancy? Journal of Lipid Research, 37, 708-726
• Papamandjaris, A.A., White, M.D., Raeini-Sarjaz, M., & Jones, P.J. (2000). Endogenous fat oxidation during medium chain versus long chain triglyceride feeding in healthy women. International Journal of Obesity and Related Metabolic Disorders, 24, 1158-1166
• Seaton, T.B., Welle, S.L., Warenko, M.K., & Campbell, R.G. (1986). Thermic effect of medium-chain and long-chain triglycerides in man. American Journal of Clinical Nutrition, 44, 630-634