Big thanks to Matt Laye for answering nutrition questions from the New York Flyers‘ Marathon Training Program. Members of the group submitted their questions as they prepare for their fall marathons.
MTP: I have been throwing up and feeling sick in my last two marathons after mile 17. I drink water every couple miles but i start throwing up in the later stages. I take GU every couple miles that I take in training as well.
Matt: A couple things could be going on. 1) You may be drinking and eating TOO much. 2) You may be running too fast for your fitness or much faster than your normal training. Each of those could cause your body to divert blood from your stomach to your muscles, which can lead to nausea.
MTP: Do you recommend any easy digestive things that are light on the stomach. I know my stomach is very sensitive and very quick with digestion. So i need something that is slow and easy on the stomach.
Matt: When running faster absorption is better. Foods that take longer to digest will sit uncomfortably in your stomach. If gels don’t work try whole foods that digest quickly like potatoes or rice based products.
MTP: Should my nutrition plan be consistent throughout a marathon? Any thoughts on whether it should change at end of race vs the beginning of the race? By mile 20 or so, it becomes a challenge to keep up with the GUs.
Matt: Eat early, eat often and hopefully you can survive that last 10k without needing an entire gel. You could try taking a smaller amount of energy on a single chomp (that way you can just leave in your mouth as well) to stave off a bonk.
MTP: How do you feel about metabolic efficiency testing and creating a diet geared to burning more fat during workouts and using less glucose for energy?
Matt: Training and increasing fitness will naturally increase your ability to burn fat during exercise (see below for more info on a fat diet)
MTP: In that vein, do you believe in a diet that is more of a 1:1 or 2:1 carb:protein proportion?
Matt: The ratio of macronutrients (carbohydrates, protein, and fat) will depend on how much training you are doing. As you increase training you should increase carbohydrates to maintain muscle glycogen levels and with less training you will need less carbohydrates. When training heavily you will require more protein. Shoot for 1.4g/kg minimum during hard training periods.
MTP: How doe you feel about a diet that has a 3:1 or 4:1 balance?
Matt: Protein should not necessarily change in terms of percentage, but rather the absolute amount is most important. Recommended amount is 1.2-1.4g/kg of body weight.
MTP: For pre-workout and post-workout drinks, do you recommend, from the choice of powdered options out there, something that is more 2:1? Do you think that there is a difference for pre-workout and post-workout drinks and, if so, what should an athlete’s focus be for each?
Matt: There are a million different powdered options out there, but the goal should be 20g of protein after hard exercise. Then add in carbs based on how long the exercise was, the longer the exercise the more carbs. A non-powdered option is chocolate milk. That’s all post workout. For hard pre-workout its best to focus on easily digestible carbohydrates 90-150 minutes pre workout and a gel less than 5 minutes before exercise. If the run is recovery/easy then nothing pre-exercise is really needed.
MTP: Are you a proponent of using products like Clif Gel Shots (which some folks use to get some degree of electrolytes during a long workout or race)? Or do you believe that steers the body away from using its stores properly by shifting to what’s being taken into the body at the time of the workout/race?
Matt: I would not worry about electrolyte intake one way or the other. If your gels have electrolytes fine, if not, that’s not reason for concern. Most important is practicing with what you plan to use in the race.
MTP: What about low-carb diets and “fat as fuel?”
Matt: Fat is fuel, but it takes more oxygen to generate a similar amount of energy as carbohydrate. For marathons a majority of your energy will be generated using carbohydrates and while you can run a marathon on nothing but fat you will not be able to go as quickly as when you use a mixture of carbohydrate and fat, which occurs naturally from training and a well balanced diet.
MTP: We know that the carbohydrate stores are lowered after 90 to 120 minutes of running so running 30-60 minutes “after” this window, in theory, should maximize fat burning and help stimulate the body to store more muscle glycogen for future runs (and races). When running (and racing) for this long, the blood glucose level also drops. Ingesting carbohydrates (either through a sports drink or energy gels) during the run, maintains the blood glucose level – as we are led to believe by sports nutrition marketing. However, how do you feel about challenging the body to run with a lowered blood glucose level with the objective of adapting to becoming better at handling a lowered blood glucose level? Do you feel that, in training, runners may want to try to slowly reduce their carbohydrate ingestion before and during this type of long run? If so, who is a prime candidate for this type of “gel avoidance”?
Matt: Becoming better at using fat can be accomplished in many ways. Running the morning after an overnight fast, increasing fitness through intervals, long runs of more than 2 hours can all help and are part of any successful marathon training. One can experiment with not using gels during a long run, but remember that during the race carbohydrates are necessary for maximal performance.
MTP: On the day of a long run, how many total calories should be taken in that day? I usually take in an extra 100 calories or so per mile based on how long the run was (i.e. 18 mile long run= 1,800 calories + 2,000 base number of calories= 3,800 total that day). Is there a certain calculation that you recommend?
Matt: While your rough guess is correct, roughly, it is highly individual on the amount of calories that you will need. After your recovery meal (which can be more processed) make sure you switch back to whole, non-processed, real foods and eat to satiety. Your body will regulate your calorie intake to an amazing degree.
MTP: Are there any particular vitamins or supplements that you recommend to fend off cold/flu viruses while marathon training? Are there any tricks to prevent catching a cold during the taper period (this happened to me right before my last marathon, and I’m afraid it will happen again)?
Matt: Eating carbohydrates (and potentially protein) immediately post exercise is the best immune system booster. Careful attention to sleeping enough and washing hands frequently (especially when flying) can help prevent sickness. There are not any specific supplements with scientific consensus to prevent sickness during training.
MTP: What are your thoughts on artificial sweeteners, namely Splenda?
Matt: No sugar >>> artificial sweeteners > real sugar. Sweeteners have their own problems of their own and might be marginally better than real sugar, but really you should not use either.
MTP: How many grams of protein per pound of body weight do you recommend daily for runners?
Matt: 1.4g/kg is a good starting point with more if you are looking to seriously increase lean muscle mass.
MTP: After a long run, aside from bagels and pretzels, what are some of foods to consider for carb intake, and how much would I need to have to equal the amount of recommended post-race carbs. In particular, good carbs. Would simply having a granola bar be enough? Or would it take two or three bars? Would I be getting the same amount of carbs from 3 bananas that I would by eating a bagel?
Matt: After a long run be sure to include some protein, at least 20 grams. You can be a little less lenient on the type of carbohydrates immediately post run, but don’t over do it. 400-600 calories immediately after would be a good target. You can use http://www.calorieking.com/foods/ to find out the caloric value of a variety of foods.
MTP: When should I begin to focus on protein? An hour after a long run? Two or three? And what would be the easiest food to digest.
Matt: Immediately after the long run. The sooner you eat the better you will recover and the sooner you can run again!
MTP: To maintain a level sufficient enough for running well during a marathon, how many calories should I be consuming per day if running between 45-55 miles per week?
Matt: The number of calories will be highly dependent upon your body weight, other activities, and weight goals. Its tough to say, but the quality of the calories will be more important. Whole foods, less refined sugar and flour, and healthy fats such as avocados and fish.
MTP: Do you recommend any specific food or drink if you are feeling nervous on marathon morning or evening? It is a gi issue I have faced on a few marathons. I try to avoid dairy. Just wondering if there is something to calm the stomach down a little.
Matt: Whatever food works before your long run use the day before your marathon. Practice your nutrition and figure out what works for you. Start with simple, refined, relatively bland foods (the type you avoid in your normal diet), such as bagels, rice, potatoes, or pasta (without heavy sauces). Avoid eating too many high fiber fruits and vegetables for a day.
MTP: How do I prevent headaches after a long run?
Matt: You are probably dehydrated and fatigued, so replacement of fluids, rest, and time.
Matthew Laye has a PhD in medical physiology and is fascinated by how exercise protects against so many different diseases. He is an Assistant Professor at The College of Idaho in the department of Health and Human Performance. When he is not in the classroom or the lab he can be found on the roads, trails, or in the mountains exploring the outdoors. He sports a marathon best of 2:23 and a 100 mile best of 13:17 and blogs at https://layeingitdown.wordpress.com/ on occasion.