“I’m so much hungrier than normal!” I frequently hear these comments as a running coach. Marathon training hunger often strikes after mileage increases or in the peak of training. It makes sense that you need to eat more – your body is burning more calories in training! Many runners worry about overeating, which just exacerbates the problem of intense hunger.
Eating for long-distance running performance drastically differs from eating if you were just completing a few 20-30 minute runs per week for fun. Your energy expenditure is much higher when you are running 40+ miles per week. You should feel strong and good in training, not cranky and ravenous. The tips presented in this article will help you eat for performance and recovery – and, as a result, quell the intense hunger that under-eating can trigger.
Disclaimer: I am a certified sports nutritionist and have my MS in Applied Exercise Science. However, this is general advice, not individual dietary guidance. If you need help ensuring you eat enough or on tweaking your diet for performance, please do consult a registered dietitian.
Overly fatigued, ravenous, and moody should not be your baseline mood, even during marathon training. If you are, these are signs of either overtraining or, more likely, undereating. Energy deficiency throughout the day has been linked to sub-optimal performance and increased risk of injury.
The risks of energy deficiency expand beyond just feeling hungry all the time in marathon training. For both male and female athletes, low energy availability (not eating enough to support energy expenditure in training) will affect performance and health. Logue et. al (2020)’s seminal review on low energy availability explores the effects of undereating on athletes. Symptoms of LEA include being hungry all the time, fatigue, constant soreness, running feeling hard, and frequent injuries.
Over time, low energy availability can build up into relative energy deficiency in sport. Poor performance, fatigue, chronic illness and injury, changes in metabolic rate, and other signs can indicate Relative Energy Deficiency in Sport (RED-S). RED-S occurs when an athlete exists in a chronic energy deficiency. Sometimes it occurs due to disordered eating, but in other cases, it occurs due to a lack of knowledge about proper sports nutrition or the influence of diets on social media. RED-S can cause amenorrhea in women, overtraining, injury, depression, and a whole host of problems that are neither conducive to performance nor overall health and well-being.
Even before the extreme cases of RED-S, insatiable hunger means you aren’t fueling your body for its energy needs based on training load. Instead of optimizing performance, you hinder your ability to recover from training and handle harder training loads. Plus, no runner feels his or her best when ravenous!
In 2018, the International Journal of Sports Nutrition and Exercise Metabolism published a study on with-in day energy deficiency in male athletes. The study found a correlation between long durations of energy deficiency throughout the day and high cortisol and low testosterone levels. The resting metabolic rates of the athletes were suppressed and catabolic markers were present. These perturbations to the endocrine system and the breakdown of lean muscle mass have consequences for both marathon performance and long-term health.
A 2023 controlled trial in the Journal of Physiology found that even short-term (10-day) low energy availability in female athletes. Compared to the control group (whose energy needs were met), the LEA group experienced reductions in muscle protein synthesis, lean body mass, metabolic rate, thyroid hormone concentrations, and nitrogen balance. What this means: the athletes had poorer recovery from exercise, hampered adaptation to their training, and loss of muscle mass.
Even short bouts of low energy availability can impair athletic performance. As outlined in a 2023 review in the Scandinavian Journal of Medicine and Science in Sports, LEA has short-, medium-, and long-term impacts on performance – and none of them are positive. Low carbohydrate intake leads to low muscle glycogen stores, which impairs training quality in marathon training. Oftentimes, low carb intake will lead to fatigue, inability to complete training, and poor adaptation to training. Athletes struggling with LEA are more likely to have lower iron levels, which further impairs performance. Injury risk and overtraining will occur at greater frequencies in athletes who undereat.
The more you run, the more your energy and macronutrient needs increase. However, appetite may be dysregulated due to how intense exercise affects hunger hormones such as leptin and peptide YY. You may not feel that hungry after your long run or marathon pace tempo – but your energy intake needs to be high.
Carbohydrates play a large role in energy production during aerobic exercise (i.e., marathon training). As you log dozens of miles per week in marathon training, your carbohydrate needs increase. Even if you eat enough calories, if you do not have enough carbohydrates, your training will suffer – and you will likely experience intense hunger. Do not be afraid of carbs!
When calculating your daily carbohydrate needs, include all hours of exercise per day. If you cross-train or lift weights, that time counts toward your training volume.
Carbohydrate (CHO) Intake for Marathon Training:
Runners also have relatively high protein needs, due to muscle breakdown in training. Typically, marathon training increases your protein needs to at least 1.2 grams per kilogram of bodyweight – with higher volume athletes needing 1.8-2.0 grams per kilogram. Since timing contributes to muscle protein synthesis, you can approach this as eating 20-40 grams of protein every 3-4 hours.
Finally, endurance athletes do need fat! As with carbohydrates and protein, your needs will be higher than general population – and increase with training volume. Generally speaking, most endurance athletes require 25-30% of their daily calories from fat to support energy intake and overall function.
Eating enough throughout the day is the simplest, most effective way to manage training hunger. For example, if you train in the morning or afternoon but eat scant meals at breakfast and lunch, you will complete your workouts on low energy. No matter how large your dinner is, you will still have chronic windows with low energy availability.
Ideally, you want to spread your calories out equally throughout the day, including around your workouts. Eating enough at each meal will keep your blood sugar and energy levels steady. Use your hunger as a cue: if you are hungry within an hour or two of eating a meal, try increasing your portion sizes or adding more quality nutrients to your meal. If you feel ravenous at certain times of day, add in a healthy snack. Your body will give you the feedback you need to know how much to eat.
As noted above, protein needs increase during marathon training. If you are hungry all the time and eating enough carbs, you want to look at your protein intake. While many runners think they get enough protein, many do not actually reach their needs for their training.
Protein promotes satiety, as it is slower to digest. Without adequate protein in your diet, you will feel hungry all the time in marathon training. Frequent doses of protein throughout the day, including shortly after you complete your run, will aid in controlling hunger. You will likely also notice that you recover better from your workouts! If you struggle to consume enough protein, protein powders can be a helpful and safe supplement.
Importantly, if you are a runner over 40 or a plant-based athlete, you may need to slightly increase your protein intake even more than recommended.
Low-carb diets can work for some runners, but those runners are often in the minority. The overwhelming body of research indicates that low-carb diets do not offer a performance benefit (as examined in this 2021 meta-analysis in Nutrients.) Likewise, no evidence indicates that gluten, dairy, or other food group restrictions benefit athletes (unless medically necessary).
Unless you have a food allergy, ethical/religious reasons, or diagnosed medical condition, there is no benefits in restricting food groups. Carbohydrates provide the energy essential for aerobic metabolism. Meat supplies many essential micronutrients (including iron) and protein. Fats, whether in the form of nuts, full-fat dairy, meat, or plant sources, support hormonal health, and reduce the risk of injury.
Restricting a group of macronutrients, whether carbs, fats, or protein, often leaves your body in some sort of deficit. As a result of this deficit, you will feel hungrier and not feel as easily satiated. Instead of restricting, give your body a healthy balance of carbs (including fiber), protein, and healthy fats.
Eating plenty of fruits and vegetables has multiple benefits. Most fruits and vegetables are high-volume for the serving size, which means they promote satiety even when you are ravenous (and have already met your macronutrient needs). Fruits and vegetables are also dense with the nutrients necessary to support your running (along with overall health).
If you are trying to avoid weight gain or lean down for race day, it is tempting to reduce caloric intake around long runs. All those gels can seem like a lot of calories and some runners become nervous about ingesting that much sugar.
However, calories before and after a long run or hard workout support your performance and recovery. If you eat too little before, during, and after a marathon training long run, you will feel ravenous as your body tries to climb out of that calorie deficit. You could actually be more likely to overeat if you restrict long run nutrition!
The exact amount will vary from runner to runner. Before a long run or a hard workout, eat a snack or meal that energizes you throughout most of the run (without having GI upset). 50-100 grams of carbohydrates will provide ample energy over a long run (1.5+ hours). Generally, low-fiber carbohydrates will best support your training without upsetting the GI system. Avoid large amounts of fat before a run. Small amounts of protein may sit well for some runners, while others may choose to skip protein.
During your marathon training long runs, you will want to consume 50-60 grams of carbohydrates per hour. Some athletes may do well with as high as 90 grams of carbs per hour. These carbs come from energy gels, chews, sports drinks, or even some whole foods.
After the run is complete, aim to eat a combination of carbs and protein within an hour. If you don’t have much of an appetite after a long run, a smoothie, protein drink, or snack to hold you over until the next meal. Post-long run nutrition is a time to prioritize quantity over quality. If all that appeals to you is a protein powder shake and a bagel, eat that!
Your metabolism does not reset at midnight. Just because you are not running once per week does not mean you need to eat less on that day – especially in marathon training. You need to eat on your rest days!
You may find that you are actually hungrier on your rest days, depending on when they fall in your training schedule. If your rest day is the day after a long run, you may be entering your rest day with a calorie deficit. In this case, you will feel very hungry – and you should honor that hunger by eating.
Life would be pretty boring if you never enjoyed a beer, bowl of ice cream, or a burger (or whatever indulgence you enjoy!). There is room in your diet for these treats on occasion, even if you are aiming to maximize your race performance. You burn a lot of calories during marathon training. Perhaps your body is signaling it needs more calories, more calcium, more iron, or just a treat. Sometimes, you just crave a certain food, and there’s nothing wrong or harmful about that.
However, if you are constantly struggling with sugar cravings, even after having a treat, your body is warning you that you are not eating enough to support your training. Intense sugar cravings occur due to inadequate carbohydrate intake. Have your treat – and then be diligent about increasing your overall carbohydrate intake each day.
3 Responses
I have to make a concerted effort to eat more mindfully during longer training sessions. I have not done a full marathon but I think this applies to half marathons as well.
Great tips as always. I found when I started adding more protein to my post-run meals (generally breakfast) I felt much better, recovered more quickly, and felt more satisfied.
When it comes to marathon training, I agree, no one food group should be left by the wayside. This is especially true in regard to fruit and veggies, which provide some of the most nutrients in condensed forms. Good tips to consider here!