Optimize Triathlon Performance: Your Ultimate Guide to Nutrient Timing

Last year, I trained for my first Ironman 70.3 and learned a lot along the way when it comes to how my body requires and handles nutrition.  Turns out, at 5’0” tall and about 110 lbs., I actually need quite a bit more nutrition than I anticipated.  

Triathlon is not just a sport that marries the disciplines of swim, bike, and run. If your goal is to not only cross the finish line, but to do so feeling as strong as possible before, during, and after, you cannot overlook your nutrition plan. This can quite literally make or break your performance. Hitting “the wall” is more often than not due to poor nutrient planning and timing. Of course, mentally you are tested as well, but the dreaded bonk is best avoided through nutrition. 

The reality is, while gender and weight play a significant role (muscle mass will increase calorie needs and increased weight will naturally increase energy expenditure), you do have other things you’ll need to consider.  Your physiology is unique to you, and sports nutrition is a learning process that has the potential to make or break your performance on race day.  You absolutely must experiment prior to your races if you want to pull the most out of yourself while competing.

FACTORS THAT INFLUENCE CALORIE & HYDRATION NEEDS: 

1. Intensity and duration of the exercise
2. Your own metabolic rate
3. Environmental conditions
4. Body composition
5. Fitness level and efficiency of energy utilization and hydration regulation
6. Climate/altitude 
7. Individual variability in physiology and response to exercise
8. Gastrointestinal tolerance for food and liquid intake under various circumstances

Considering these factors and adjusting nutrition plans accordingly is crucial for optimizing performance and preventing dehydration or inadequate energy supply during training and competition.

I’m thankful I took the time (multiple times) to practice my nutrition in different conditions and distances leading up to my race. New Jersey in the summer months can be hot as hell and humid, cool and rainy, or completely perfect conditions to train and race in.  It is not consistent and I needed to be prepared for whatever Atlantic City would bring that day.  It turned out she brought torrential downpours on the bike and then heat and humidity on the run.  Mother nature was playing games with us that day, and I felt well-prepared for it.

Anyway, back to training and nutrient timing.  

WHAT IS NUTRIENT TIMING

Nutrient timing is quite simply, the strategic timing of nutrient intake, such as carbs, proteins, fats, water, and electrolytes at specific times relative to exercise sessions and races to optimize performance, enhance recovery, and support training adaptations. The body’s nutritional needs vary depending on factors such as timing, intensity, and duration of the exercise and the individual’s physiological characteristics. 

BENEFITS OF NUTRIENT TIMING

Nutrient timing can have a significant impact on both training performance and race results in endurance sports. Here are a few ways it may affect your training and racing:

Optimize Energy Availability: Nutrient timing, particularly with regard to carbohydrate intake ensures your muscles have an adequate supply of glycogen.  This is the primary source of energy and having your stores topped off can delay fatigue, improve endurance, and help maintain performance during intense training and races.

Support Recovery: Consuming a proper combination of carbs and proteins after training and racing help replenish glycogen stores, as well as repair muscle tissue to promote recovery.  This can also help reduce muscle soreness, speeding up recovery time and enhancing overall training adaptations.

Support Muscle Repair and Growth: This is important after your endurance training, and even more so after strength training exercise.  Protein post-exercise provides essential amino acids, which are necessary for muscle protein synthesis, helping to rebuild and strengthen muscles over time. 

Hydration and Electrolyte Balance:  This is crucial for maintaining performance and preventing dehydration.  Consuming fluids that contain electrolytes during training sessions or races can help maintain hydration status and support optimal performance. Dehydration can impair thermoregulation, cardiovascular function, perception of effort, cognitive function, and recovery.

Managing Weight and Body Composition: Carbs and protein consumed around  your workouts can help fuel performance, preserve lean muscle mass, and support fat loss or muscle gain.

Maximize Adaptation to Training: Consuming carbs and protein at the key times may enhance your body’s ability to repair itself, adapt to training stress, and improve overall performance over time. 

KEY ASPECTS OF NUTRIENT TIMING IN SPORTS

• Pre-exercise nutrition: Consuming a meal or snack containing carbohydrates and a moderate amount of protein a few hours before exercise can help ensure adequate glycogen stores in the muscles and liver, which are important for sustaining endurance activities. You will also want to hydrate properly before exercise begins.
• During exercise nutrition: For longer endurance events lasting more than 60-90 minutes, consuming carbohydrates during exercise can help maintain blood glucose levels and delay fatigue. This is typically done using sports drinks, gels, chews, or bars that provide easily digestible carbohydrates. The timing and amount of carbohydrate intake during exercise depend on factors mentioned above, such as exercise duration, intensity, and individual tolerance. Fluids should also be taken during exercise and depends on your GI tolerance and the type of activity.
• Post-exercise nutrition: Consuming a combination of carbohydrates and protein within the first 15-30 minutes and then two to four hours after exercise is crucial for replenishing glycogen stores, repairing muscle tissue, and promoting recovery. Including some healthy fats can also be beneficial for overall nutrient balance. This post-exercise meal or snack helps optimize recovery and prepares the body for subsequent training sessions.  Again, continued hydration is key, along with electrolytes.
• Individualization: Nutrient timing strategies should be individualized based on factors such as training goals, body composition, gastrointestinal tolerance, and personal preferences. Experimentation with different timing and types of nutrients can help athletes identify what works best for them.

UNDERSTANDING THE KEY PLAYERS – CARBS, PROTEIN, FAT, WATER

Hopefully you are starting to realize nutrition plays a crucial role in how you perform and recover from your training sessions.  You can’t out-train a bad diet.  If you are putting hours a week into your training, you should have a nutrition plan in place that compliments your efforts.  While micronutrients and supplements have a significant place in your diet and program, the focus here will be on the macronutrients (protein, carbohydrates, fat) and water, and how you can utilize nutrition timing to optimize your results.      

Carbohydrates

Approx 80% of stored glucose is found in the muscles.  The amount of glycogen, which is the stored form of carbohydrates, varies among individuals.  It is influenced by factors such as muscle mass and training status. On average, muscle glycogen stores can range from approximately 300 to 600 grams. However, this value can increase with carbohydrate loading strategies before endurance events.

Carbohydrates are the primary source of energy for the body. When consumed, they are broken down into glucose, which is used by cells for energy production. Glucose is also the preferred fuel for the brain and central nervous system. Adequate carbohydrate intake ensures proper cognitive function. Carbs are also important for fueling muscle activity during exercise and physical activity. Glycogen, the stored form of glucose in muscles, provides energy for sustained or intense exercise. Certain carbohydrates, such as fiber, play a crucial role in digestive health by promoting regular bowel movements, reducing the risk of constipation, and supporting a healthy gut microbiome.

Proteins

Protein can be used for energy but is very inefficient. It is not a preferred source and is usually only used in cases of calorie restriction or the later phases of long endurance events. Proteins are the building blocks of muscle tissue and are essential for muscle maintenance, repair, and growth. 

During periods of physical activity or exercise, protein synthesis increases to repair and rebuild muscle fibers. Many enzymes, which are crucial for various biochemical reactions in the body, are made up of proteins. These enzymes facilitate processes such as digestion, metabolism, and immune function. 

Proteins play a role in hormone synthesis and regulation. Hormones are chemical messengers that control numerous physiological processes, including metabolism, growth, and stress response.  Certain proteins, such as antibodies, are essential for a healthy immune system. They help identify and neutralize pathogens, such as bacteria and viruses, protecting the body from infections.

Fats

Fats are the most concentrated source of energy, providing more than twice the energy of carbohydrates and proteins per gram. They serve as a long-term energy storage mechanism, stored in adipose tissue for later use.

Fats are integral components of cell membranes, providing structure and stability to cell membranes and ensuring proper cellular function. Body fat serves as insulation to help regulate body temperature and protect organs from physical damage and shock. Certain vitamins, such as vitamins A, D, E, and K, are fat-soluble, meaning they require dietary fat for absorption. Fats help transport these vitamins through the bloodstream and into cells where they are needed.

Water

As humans, we lose 2-3 liters of water per day through normal bodily functions.  When you combine that with training, humidity, and individual responses, that amount naturally increases.  And it can increase quite a bit.  On a daily basis, you want to ensure you are replacing lost water.  As mentioned earlier, dehydration can impact your performance, recovery, and overall health in a number of ways. None of which will benefit you in training or racing.

PUTTING IT INTO PRACTICE

Your training cycle goes through a number of phases throughout the year.  With each phase, your nutrition plan should change, as well.  Below are general guidelines, but keep in mind that each individual responds differently, physiologically we are different, some may be more tolerant of higher quantities of carbs, while others may be more metabolically efficient at using fat for fuel.  

Ultimately, you will ALWAYS want to practice what you plan to do on race day.  Experiment with different conditions, training intensities, and nutrition strategies.  You are an individual, and your training and nutrition plan should reflect that. 

Nutrient timing while training

When I discuss pre-training, this window of time is 15 minutes up to three hours beforehand.  I understand that depending on the time of day that you train, this window of time can vary, and pre-nutrition is not always feasible.  Carbs, water, and electrolytes are the priority, while protein is okay, and fat is not so necessary. 

During training, nutrition becomes important when activity is greater than 45-60 minutes.  The focus is on carbs, fluid, and electrolytes. After training, the goal is to consume something within the first 15 mins post workout, and then in 2-4 hour intervals throughout the day.  Post-exercise and race, you’ll want to incorporate a more balanced approach to carbs,protein, fat, fluid and electrolytes.

The main phases that I’ll focus on are your preparatory phase and competition phase.

Preparatory (base) is when you may focus more on building endurance, strength, facility, and technique. Competition (race) phase, the focus may shift to speed, economy, skills, and power. During your transition (off season), your focus will likely be more geared towards recovery, pre-hab,and rehab, with less structure.

I won’t discuss the off-season here.  During that time, your focus should be on maintaining a balanced, healthy diet.  Your volume and intensity likely decrease, and your glycogen stores should remain relatively balanced with a regular eating plan.  This is a great time to dial into more intuitive eating and understanding your hunger.

Below are suggested intakes for nutrient timing based on the phase that you are in.  Again, these recommendations are broad, and you need to consider your own physiology and adaptations.  The recommendations are for fluids/electrolytes, carbs, protein, and fat.  Nutrition is NOT one-size-fits-all, and my goal is to give you a starting point that you can try out and tweak based on your training intensity, environment, sweat rate, metabolic rate, and any other factors that can impact how your body processes and utilizes nutrients. 

Preparatory/Base Phase:

Pre-training

• Water: 8-24 oz based on body weight around four hours prior; 4-12 oz two hours prior with electrolytes
• Carbs: Nothing or a light snack, up to 20 grams of carbs.  
• Protein: Nothing or a light snack, up to 20 grams of protein
• Fat: minimal 
• Electrolytes: additional beyond what’s found in food likely uneccesary

During

• Water: 12-32 oz/hour depending on environment, sweat rate, duration/intensity
• Carbs: Training under three hours, nothing; Greater than 3 hours 10-40 grams/hour
• Protein: Less than 5-6 hours, no protein needed
• Fat: Usually no fat unless ultra training
• Electrolytes: based on sweat rate/sodium concentration; or 300-2,000mg/hour; mixed electrolytes are ideal

After

• Water: 16-24 oz for every pound lost
• Carbs: balanced cho/pro/fat meal or snack
• Protein: balanced cho/pro/fat meal or snack
• Fat: balanced cho/pro/fat meal or snack
• Electrolytes: found in snack/meal

Late Preparatory/Early Competition 

Pre-training

• Water: 8-24 oz based on body weight around four hours prior; 4-12 oz two hours prior with electrolytes
• Carbs: 0.5-2.2 grams/kg body weight
• Protein: 0.3-0.35 grams/kg body weight
• Fat: meal/light snack depending on mode/training goals
• Electrolytes: dependant on your sweat late and potential for sodium loading

During

• Water: 12-32 oz/hour depending on environment, sweat rate, duration/intensity
• Carbs: 30-60g/hour
• Protein: Combine with carbs
• Fat: Usually no fat unless ultra training
• Electrolytes: based on sweat rate/sodium concentration; or 300-2,000mg/Na/hour; mixed electrolytes are ideal

After

• Water: 16-24 oz for every pound lost
• Carbs: 1-1.5g/kg 
• Protein: 20-40 grams
• Fat: Minimal to none
• Electrolytes: found in snack/meal

Competition Phase

Once you’ve made it to race day, you should have practiced what you will implement in competition.  What worked in training under similar intensities and conditions should be what you put into play.  The saying is true – do not try anything new on race day.  I have done this in the past and it did not work in my favor.  Trust the process and race using what you trained for.

FINAL THOUGHTS

Overall, nutrient timing is a valuable tool if you are an athlete looking to optimize your training performance and race results. By paying attention to when and what you eat before, during, and after exercise, you can support energy levels, enhance recovery, promote muscle repair and growth, maintain hydration, and maximize adaptation to training, ultimately leading to improved performance and race outcomes.

If you’d like to dig in a little deeper about nutrient timing and your own practices, let’s connect. Send an email to lauren@settingthepacenj.com with the subject “Nutrient Timing” to get started!

References

My information comes from my training through UESCA’s Endurance Sports Nutrition Certification and the accompanying book “Nutrition Periodization for Athletes” by Bob Seebohar.