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Daily Nutrition

Stop Making These Nutrition Mistakes

Nutrition shouldn't be rocket science. Here's where most runners go wrong.

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I get it.  You heard about the latest nutrition trend and want to incorporate it right away into your daily routine to try and improve your running performance. For many runners, failing to optimize performance comes down to the fact that they don’t have their nutrition basics dialed in.  When I work one-on-one with runners to improve their nutrition for health and performance, it’s not that someone is deficient in a weird vitamin or nutrient, or that they need to eat a certain diet for their blood type (don’t do that). More often than not, it’s that they haven’t quite nailed their nutrition basics.

While it’s not exactly rocket science, dialing in the following nutrition principles can help you make the biggest health and performance gains.  Let’s take a look at the most common mistake I see runners make when it comes to nutrition.

RELATED: Are You Making One of These 3 Nutrition Mistakes?

#1) Not Eating Enough:  This is the most common mistake runners make.  No matter what your goals are, if you aren’t eating enough, it can have a cumulative effect and lead to imbalances in hormones, nutrient deficiencies that can lead to a higher risk of injury and illness, and long term ability to adapt to your training. Research shows that within-day energy deficits have detrimental effects on health and performance, particularly for female athletes.   Some signs that you might not be eating enough are poor sleep patterns, inability to recover from training, frequent illness or injury, frequent bouts of hunger, and a loss of period (amenorrhea) for female runners.

Easy Solution: Making sure you have a loose eating pattern set up for yourself, as well as a full pantry and go-to snacks to make it easier to eat enough.  Avoid restricting macros or any food-groups, and have a plan to fuel pre-run.  If you are having trouble dialing this in, reach out to a sports dietitian for help.

RELATED: Elyse Kopecky Wants You to Say No to Dieting

#2) Not Focusing Enough on Pre- or Post Workout Nutrition:  If you are concerned about performance, honing in on your pre or post-run nutrition is a critical step.  Not eating enough or timing things poorly beforehand can lead to higher incidences of GI distress, increased risk of injury and a higher risk of bonking.  Post-run, your nutrition can influence whether you come back strong the next day and can increase or decrease your injury risk.  Making sure you’re eating enough of certain nutrients like protein will give your body the best shot at recovering and being ready to roll the next day.

Easy Solution:  Get in the habit of eating something before your runs that contains mostly simple carbohydrates and a little bit of protein.  Some ideas include a banana with peanut butter, toast with sunflower seed butter, or quick cook oats with almond butter.  After running, drinking your calories can be a good option, especially if you are not hungry or in a rush.  Either whip up a banana smoothie with some Greek yogurt or simply add protein powder to some sweetened almond milk.

#3) Not Practicing an Inter-Run Fueling Plan: Winging it during long runs and adventures might seem like a good idea….until it’s not.  There are three things that affect your body’s ability to run well for long periods of time: the volume of fluids consumed per hour, the amount of electrolytes consumed per hour, and amount of calories/types of calories consumed per hour.  These three pillars of inter-run nutrition work best when dialed in to work together.  Get in a hole in one of them, you risk stomach distress, bonking, and having to slow down.

RELATED: Ultrarunner Magda Boulet’s Hard-Earned Nutrition Tips

Easy Solution: Start with choosing a fluid per hour goal, real food blend/gel option, and 2-3 real food options for fueling.  Put together an organized plan for yourself aiming for the general recommendations of 200-300 calories per hour, 250-500 mg of sodium per hour, and 16-20 oz of fluids per hour.  Put into practice during your long runs and adventures.

#4) Not Hydrating Well: Being even two to four percent dehydrated can lead to a decrease in running performance.  Water is critical to delivering oxygen to the muscles, assisting with nutrient absorption, and regulating body temperature through sweat.  Signs and symptoms of dehydration include: dizziness, dry lips and skin, increased body temperature, decreased pace and fatigue and darkened urine.

Easy Solution: Start with calculating a general estimation of your fluid needs per day.  ½ your body weight in ounces plus 16-20 oz for every hour of exercise you are doing is a good place to start.  Once you dial in a goal, aim to increase your current intake by 8-16 oz per day for a week or two, and gradually increase until you reach your goal.

Do you have a question for our RDN? Send your trail-running-nutrition quandaries to

Kylee Van Horn is a licensed Sports Registered Dietitian and competitive trail runner.