What should endurance athletes eat? We asked a Sports Dietitian!

Nutrition comes up on Slack relatively often. We all want to optimize our performance, and many coaches, other athletes, and even our families think they know what we should do. We wanted to ask an expert some of the questions we commonly ask and banter about in 100-message threads. Will this make Slack quieter? Doubtful - there’s always something new to talk about.

I was lucky enough to work with Amy Stephens last year when I was training for the NYC Marathon, and because she is a great person with a high degree of patience, she agreed to answer our litany of questions in an interview.

Amy is a Sports Dietitian and eating disorder specialist who works with the NYU Cross Country Team and Empire Elite Track Team. Amy has recently appeared on Runner’s World “How to Master the Half Marathon” educational series. You may see Amy on nutrition panels for Runner’s World or competing in NYRR road races. The best way to contact Amy is through her instagram account @Amystephensnutrition. 

I hope you’ll enjoy our conversation and find some new tips and strategies to stay on top of your nutrition!

What are some common mistakes you see endurance athletes with day jobs making in their nutrition choices? 

Getting fueling right for workouts. Many athletes with busy jobs find it hard to be on point for fueling early morning or late day workouts. Eating too much can cause GI issues and too little will make it hard to hit workout goals. I encourage athletes to spend some time creating a fueling plan that works for them. You might need to set an alarm or write out your fueling plan that provides plenty of time to digest. Figure out what works for you and repeat it over and over on workout days. 

Another common mistake is refueling after a workout. Recovering after a workout is just as important and fueling for a workout. Think of the recovery meal as part of your workout. Eat a combination of carbohydrates and protein within one hour of completing your workout to help restock glycogen and repair damaged muscle tissue. Food is the best recovery tool and eating right after will help your body get stronger for the next workout session. 

Sample meal plan for an evening workout 

9am Breakfast - Oatmeal with fruit 

1pm Lunch - Sandwich and side salad 

4pm Pre workout fuel - banana and peanut butter, peanut butter pretzels or Clif bar 

630pm workout

8pm Refueling dinner - grilled chicken, baked potato and roasted broccoli with olive oil. Dark chocolate or fruit 

Optional snack - yogurt or toast with peanut butter 

What do you recommend for nutrition before early morning workouts for endurance athletes with day jobs? Would you ever recommend fasted training? Are there specific grams of carbs we should be looking to consume? 

Early morning workout: 

How you fuel before a workout depends on duration, intensity and prior workout. Shorter workouts can be done without food while longer workouts require careful attention to fueling. The purpose of fueling before a workout is to top off glycogen from the overnight fast. It’s important to recognize that everyone is different and what works for one person might not work for someone else. The information here should be a good starting point and you might need more or less food depending on how you feel. 

Choose foods with plenty of carbohydrates which are the best source of energy before a workout. Including some easily digestible protein is also important to keep energy levels stable. For longer workouts, start your fueling plan early to prevent bonking. 

Shorter Workout lasting less than 90 minutes 

Before 

Fluids: sip 10-20 oz fluids 

Carbs: Fueling before is optional. If you feel hungry or you know that fueling helps your performance, choose foods with carbohydrates from sports drinks or gels and fluids. 

Here are some examples: 

Toast with peanut butter, banana 

Clif bar

Oatmeal with sliced banana 

Medium Workouts lasting 90 minutes - 2 ½ hrs 

For workouts more than 90 minutes, your body needs carbohydrates before and during the exercise to keep energy levels stable and prevent bonking. Don’t wait until you feel tired to start fueling. Prevent bonking by fueling early and often. 

Before 

one-to-two hours before, eat a combination of carbs and protein 

Here are some examples: 

Toast with peanut butter 

Oatmeal with fruit 

During 

Fuel: 30-60 grams carbohydrates from sports drinks or gels Hydration: fluids (10-32 oz per hour) with electrolytes. Electrolytes are especially important on warmer days or if you have a higher sweat rate. 

Longer workouts lasting more than 2 1/2 hrs 

Extended exercise sessions require higher carbohydrate intake per hour due to the combination of energy expenditure during the workout and the provision of basal energy requirements. 

Before 

one-to-two hours before, eat a combination of carbs and protein 

During 

Fuel: 60-90 grams carb per hour (240-360 calories/hour) from gels, sports drinks, fruit, pita with peanut butter, nutrition bars such as Clif Hydration: fluids (10-32 oz per hour) and electrolytes are recommended 

Fasted training depends on fitness goals and duration of activity. For workouts up to 90 minutes, your body can rely on stored energy. However, if your workouts are more intense or last longer than 90 minutes, you will need to fuel with carbohydrates before and during a workout to prevent bonking. 

Are there any supplements you commonly recommend for your athletes? We've had curiosity about a few - Athletic Greens (which we think is all marketing), Ketones (don't get us started), and collagen (mainly asked by the more middle aged runners with tendon problems) 

Recently, I co-authored a blog with NY Run Academy on the best supplements. NY Run Academy is a coaching and physical therapy team comprised of elite runners, triathletes and cyclists. For the questions you asked, here are some thoughts.

Ketones 

During times of exercise when glycogen and carbohydrates stores are low, the body will use ketones for energy. This includes ketone bodies, namely D-β-hydroxybutyrate (βHB), acetone and acetoacetate (AcAc). This type of energy source is in great abundance in the body however it can only be utilized during lower intensity training (ie. vo2max <70%). Ketone supplementation can be helpful for athletes that require a steady state of energy usage such as long endurance events at slower paces. However, during surges or competitive times where there needs to be a kick, glycogen is the primary energy source. Ketones are not ideal for more competitive events. (Leckey). Studies show that supplemental ketones have not shown an improvement in performance. In addition, ketones take longer to digest and have a higher incidence of GI issues. While there are some products on the market that market to cyclists, I’d recommend testing it out to see how your body feels. 

Collagen

Collagen has been shown to support tendon and ligament health when taken correctly. The best time to use collagen is one hour before or immediately after a workout. Studies have shown that 15 grams of collagen from bovine (cow) with vitamin C can improve ligament and tendon health(Shaw, 2017). Foods sources of collagen are from red meat, poultry, fish and dairy. 

Here’s a great podcast that discusses everything you need to know about collagen.

Athletic Greens 

Athletic greens cannot substitute for consuming fresh fruits and vegetables. Whole foods provide essential fiber, probiotics, antioxidants, and various nutrients. Unlike supplements, which lack regulation by a governing agency, there is no guarantee that the contents match the label. While third-party testing may ensure certain batches are free from harmful additives, it does not guarantee supplement efficacy. 

Here are some simple ways to include fresh fruits and vegetables in your diet: 

● Include fruit in yogurt and smoothies. 

● Enjoy berries, bananas, and apples as convenient snacks. ● Incorporate salads or roasted vegetables into your meals. 

Are the more premium gels / drink mixes like Maurten or Precision Nutrition worth the extra cost over something like Gu in your opinion? 

Occasionally, investing in pricier products can be worth it. Premium pre-made gels and drink mixes often boast an optimal ratio of carbohydrate sources, deriving from both glucose and fructose. Additionally, they provide a range of delicious flavors.

Below are a couple of recipes that are similar to the more expensive products. 

Orange lemon blast 

1/2 cup orange juice 

1/4 cup lemon juice 

1 cup coconut water 

1 cups cold water 

2 tbsp honey or 3 tbsp maple syrup 

1/8 tsp salt. 

Yields 20 oz with 300 mg sodium 

Note: 1 tsp salt = 2300 mg sodium 

Red zinger 

1/2 cup pomegranate or cranberry juice 

1/4 cup lemon juice 

1 1/4 cup coconut water 

2 cups cold water 

2 tbsp honey or 3 tbsp maple syrup 

1/4 tsp. salt 

Yields 1 Liter with 600 mg sodium 

How do you advise your athletes around avoiding RED-S and other problems from not eating enough calories? How can we be smart about making sure we're eating enough? 

REDS which stands for relative energy deficiency in sport occurs when there is a higher amount of energy expended and not enough food consumed. This creates a gap and underfueling. Over time, if this gap is not corrected, REDS will develop which will undermine performance and overall health. 

In order to prevent REDS, follow these tips below to prevent RED-S.

1. Make sure to fuel up and refuel around workout sessions. 2. Eat on a schedule - that way you can ensure that your body is getting enough food. Take a few minutes each evening to plan out your meals and snacks the following day. 

3. Carry snacks in case you get hungry between meals. This is especially helpful as training demands increase. 

4. Recognize the signs and symptoms of underfueling: 

Signs and symptoms of underfueling 

Fatigue 

Poor appetite 

Loss of period for women / low testosterone for men 

Lightheadedness 

Dizziness (especially when standing up) 

Chronic colds or viruses 

Frequent injuries 

Poor recovery after a workout (frequent soreness) 

Not seeing fitness improvements, despite heavy training 

Insomnia 

Irritability/poor mood 

If you experience any of these symptoms, it's crucial to reassess your eating habits. Collaborating with a dietitian can help ensure you're eating enough to sustain your current level of activity or training intensity. 

Signs that you are fueling properly: 

Feeling good at the end of a workout 

Feeling hunger and satiety throughout the day 

Have a regular menstrual cycle/normal testosterone levels Sleeping well 

Infrequent injuries 

Feel tired but not overly fatigued during the day 

Positive mood, excited for workouts

Able to focus on work 

Have you heard of using straight sugar mixed with water as a drink mix to save money? Can this be a good strategy?

This can work, the only concern is that you don’t want to concentrate the mix too much because it can cause GI issues. A combination of glucose and fructose which is found in table sugar (sucrose) will help to maximize absorption. Aim for 6-8% solution by following this breakdown: 

1 Tbsp table sugar, honey or maple syrup per 8 oz cup of water 

What are some recommendations you commonly make for post-workout nutrition? How important is timing in your recovery meal / snack? 

Refueling after a workout is essential to help restock glycogen and repair damaged muscle tissue. Try to refuel within 30-60 minutes after a workout to kickstart recovery because the body is primed to absorb the maximum amount of nutrients. Include carbohydrates and high quality proteins with a ratio of 4:1 or 3:1 carbohydrates to protein. 

Here are some great refueling meal ideas: 

Eggs and toast 

Sandwich (chicken or hummus) 

Oatmeal made with milk, topped with fruit 

Smoothie with fruit and milk 

Pasta with chicken and side salad 

If you need a quick on-the-go breakfast, are all bars created equal? Is a banana better?

Breakfast is an important meal for athletes because it helps replenish glycogen from the overnight fast. Try to start eating within two hours of waking up with a nutritious breakfast. If you need a quick grab-and-go 

nutrition bar, look for bars with whole food ingredients and have at least 30 grams carbohydrates, 10 grams protein protein and at least 4 grams of fiber. 

Meal prepping breakfast is easy. Here are a few quick ideas that you can prep the night before and grab as you head out the door for work: 

Overnight oats 

Toast with peanut butter 

Banana and peanut butter or handful of nuts 

Plain yogurt with fruit 

Waffles and scrambled eggs 

Cottage cheese on toast with a side of fruit 

What do you recommend to athletes interested in gut training? Is there a limit where you say a certain number of grams of carbs per hour is too much? 

Our gut acts as a barrier wall to the outside environment and protects our bodies from absorbing harmful toxins. During times of illness, stress or eating poorly, our gut barrier is compromised and toxins pass through into our bodies and make us sick (ie. diarrhea, nausea, vomiting). Gut training refers to the training of our guts to be healthy and absorb nutrients so we can continue to perform at high levels. 

Taking in carbohydrates is essential for high performing athletes. The more carb our bodies can absorb, the higher intensity our bodies can withstand.

In order to train the gut, we need to be eating regular meals and having normal bowel movements. 

Gradually, over a few weeks, increase the amount of carbohydrates consumed during training until you reach your goal. As you introduce more carbs, the gut will adapt by upregulating enzymes that will break down food into energy. 

References 

Leckey JJ, Ross ML, Quod M, Hawley JA, Burke LM. Ketone Diester Ingestion Impairs Time-Trial Performance in Professional Cyclists. Front Physiol. 2017 Oct 23;8:806. doi: 10.3389/fphys.2017.00806. PMID: 29109686; PMCID: PMC5660098. 

Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. Am J Clin Nutr. 2017 Jan;105(1):136-143. doi: 10.3945/ajcn.116.138594. Epub 2016 Nov 16. PMID: 27852613; PMCID: PMC5183725.