Endurance Nutrition: Planning your Fuel for Long Course Triathlons

July 26, 2018

Nutrition is often cited as the 4th discipline of triathlon, and rightfully so as race day nutrition plays an important role in providing energy and has an impact on your performance. Just like your training plan in the months leading up to a race, your nutrition plan is an important part of your training - testing your hydration, food(s) and/or sports supplements is an integral part of the process. Studies even show that your gut can be trained to tolerate the right types and amounts of fuel for your body during activity.

 

Here are the main tried and tested expert guidelines that are backed by years of evidence in the field of sports nutrition.

 

Hydration: Aim for 5-12 mL/kg body weight/hour of total fluids (sports drink + water). Stick to the upper end of this range on the bike and hot conditions, and the lower end during the run where it’s not as easy to drink.

 

Carbohydrates: Aim for 30-60 grams of carbohydrates/hour, and up to 90g/hour for endurance races 3 hours or longer. Choose products offering multiple transporter carbohydrates (ex. combination of maltodextrin, glucose and fructose), especially for log distances and if going over 60g/h. Combining glucose with fructose increases the rate of carbohydrate oxidation (which means more energy to the working muscles!). Choose complex carbs (ex. bars) towards the beginning of your bike which will be more slowly digested than simple carbs (ex. gels, chews, sports drink). During the run, you will be closer to the lower or middle end of this range (30-45 g/hour). 

 

Protein: Most bars contain some protein. Protein takes longer to digest than carbohydrate so it can cut that feeling of hunger (especially for 70.3 and full 140.6 distances). Try to keep your protein intake on the bike  portion of the race only, at a maximum of 10 grams per hour and not during the last hour of the bike to give your body time to digest and avoid any digestive problems.

 

Sodium: Most athletes do well with 250-500 mg sodium per hour. If you are a “salty sweater” (often have white, salty residue on your tri apparel after training), you can increase your sodium intake to around 1000 mg (1g) per hour by choosing products with more salt, salt caps or pretzels.

 

Sports dietitian tips:

  • Check the course and identify aid stations as well as the nutrition that is being offered on-course. Test those products, and if you tolerate them well, great! Although you should always have back-up, you’ll have less to bring with you on race day.
  • Check the weather forecast (as if you didn’t already obsess over it!). Hot and humid conditions call for increased hydration and electrolytes, whereas in colder conditions you may want to bring extra fuel with you as you will likely expend more energy keeping your body warm.

 

If you are having issues fueling properly for your race distance, suffer from digestive issues on course or have a general lack of energy, consult a sports dietitian who can help guide you.

 

Stephanie Jamain, M.Sc, RD, CSSD
Sports Nutritionist