Nutrition has always been a crucial player in my own running victories and failures (ahh, so many failures). My experience over the years has helped me form a few nutrition do’s and don’ts during training. Keep in mind that nutrition is very individual and there will always be exceptions but overall, I think this list is applicable for most runners.

Do: eat carbohydrates

This sounds easy, but you would be surprised how carbohydrates and carbohydrate containing foods are vilified by runners all the time. Possibly because of the recent popularity of the ketogenic diets for sports performance. The bottom line is that carbohydrates are your body’s main and most preferred source of energy. If you’re going to be running the mileage it takes to train for a marathon, your body needs carbohydrates to fuel these miles. Period, end of story. Without them, performance will suffer, the body will be extremely stressed, and you will eventually feel fatigued and unmotivated!

Do: listen to your body’s cues

Marathon training is stressful on the body, and everybody handles this stress differently. Not better or worse, just differently. One common manifestation of training often accompanied by under fueling whether we mean to or not, is the loss of a menstrual period in females. This is not normal and it’s not something to ignore, even if it seems like evidence that you’re working really hard (NO!). This is our body’s way of telling us that something is not right, it doesn’t have enough fuel to function and is slowing or shutting down the reproductive system to conserve energy as it’s not essential for living. This is not normal. A missed period is a sign that you need to look at your training, your training in general and your nutrition because something is not right (Ideally- work with a dietitian who can help!). Not addressing the issues can lead to bone loss and stress fractures, disordered eating, and have long term health effects.

Do: plan post run recharge

Lack of appetite is after a long run or tough workout is common. It may take some runners an hour or two before they feel up to eating a meal. But this is too long! And one of the few instances where I would say eating mindfully isn’t the most beneficial because it’s important to have some nutrition shortly after a hard run regardless of hunger levels. This is because your body is the most efficient at replenishing glycogen stores that were depleted during the run and your muscles more efficient at using protein to rebuild from the stress and damage of a hard run. A recent study found that immediate ingestion of carbohydrates and protein after a hard run may create a more positive bone turnover balance ( AKA=stronger bones!). Waiting a few hours before eating something after a run can cause lingering discomfort, delay recovery and leave you feeling fatigued for the rest of the day. Getting some carbohydrates and protein into your system within 30 minutes of finishing your run is a great goal to help maximize recovery and extremely easy. For example: chocolate milk or smoothie with fruit and Greek yogurt work well. Once your appetite is back, have a substantial meal.

Don’t: “diet” during your training for a marathon

While some people may inadvertently lose weight during marathon training, this should not be the primary goal. Restricting food intake while ramping up the miles takes the focus away from what the body physiologically needs->nourishment through protein, carbohydrates and fat. Hunger levels inevitably increase during marathon training because we need more energy to support all the running. Dieting during marathon training (or any time) can fuel an already unhealthy relationship with food or create one and often leads to dissatisfaction on race day because the body is stressed and under fueled.

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I would love to learn from you what your experience is with training for a marathon.

If you ever need any help or support with establishing a healthy relationship with nutrition and training or just figuring out how to eat healthier to improve your health, I’m an email away! Check out my coaching programs here.

Carol Aguirre MS, RD/LDN