Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In


Daily Nutrition

Are You Making One of These 3 Nutrition Mistakes?

The most common mistakes runners make and how to fix them.

Lock Icon

Become a member to unlock this story and receive other great perks.

Already have an Outside Account? Sign in

Outside+ Logo

All Access
40% off Season Streamings Sale
$1.14 / week*

  • A $500 value with everything in the Print + Digital Plan plus 25+ benefits including:
  • Member-only content on all 17 publications in the Outside network like Outside, SKI, Backpacker, Clean Eating, and more
  • Today’s Plan training platform with customized programs
  • Gaia GPS Premium with hundreds of maps and global trail recommendations, a $39.99 value
  • Download your personal race photos from FinisherPix* for one race (up to a $100 value).
  • Get up to $30 off your next race and $30 off race fees every year you are a member through AthleteReg*
  • Exclusive discounts on gear, travel, and more
  • Annual subscription to Outside magazine
Join Outside+
Trail Runner Magazine

Print + Digital
50% Off Holiday Sale
$0.50 / week*

  • Annual subscription to Trail Runner magazine
  • Access to all member-exclusive content on
  • Ad-free access to
Join Trail Runner

*Outside memberships are billed annually. Print subscriptions available to U.S. residents only. You may cancel your membership at anytime, but no refunds will be issued for payments already made. Upon cancellation, you will have access to your membership through the end of your paid year. More Details

It’s easy to know when you aren’t eating enough calories because symptoms such as unplanned fatigue, weakness, poor recovery, hormonal issues, nutrient deficiencies, and increased susceptibility to illness and injury make you feel sluggish and prevent you from staying consistent with training.

To avoid the performance-limiting consequences of not meeting your energy needs, you may assume that the best way to support your training is to simply eat more food. Although it makes great sense (food = calories = energy), it is not uncommon for many endurance athletes  to gain weight when training volume or intensity increases, despite expending a significant amount of calories on a daily basis.

Luckily, you don’t need a Ph.D. (or the genetics of an elite) to eat like a pro. Here are a few step-by-step tips to ensure that you don’t nutritionally overdo it when you step up your training regimen.

RELATED: What Your Weekly Training Plan Should Look Like

Mistake: Disorganized Eating

Fix: Structured Eating

Your body will function at its best with a varied, nutrient-dense diet supported by structured meals and snacks. Just because you are training for an event, this doesn’t give you an excuse to eat whatever you want. On a daily basis, your foundational style of eating should not vary much, because you need to eat adequate carbohydrates (e.g., potatoes, rice, beans, lentils, whole grains), quality protein (animal and/or plant) and healthy fat (e.g., nuts, seeds, oils, avocados), along with key vitamins and minerals (e.g., calcium, magnesium, B vitamins) to support your metabolic and health needs. While it’s not necessary to calculate every morsel of food that goes inside your body, aim to consume three to five grams per kilogram of body weight of carbohydrates, 1.4 to 1.8 grams per kilogram of protein and 1 gram per kilogram of fat on a daily basis, broken down into three substantial meals and a snack between, so that you are eating every two to three hours.

RELATED: Why Eating Protein Before Bed May Benefit Your Workout

Mistake: Training To Eat

Fix: Eating To Train

Training places stress on the body, but it’s intentional and necessary to help you improve strength, power, speed, and endurance. Without adequate energy, your body can’t perform at full capacity. Consume a small pre-workout snack of carbohydrate and protein (and a little fat) around 20 to 60 minutes before your workout. Some simple ideas are yogurt with granola and berries, or a banana with nut butter and a hardboiled egg. Aim for 80 to 200 calories of easy-to-digest foods. Post-workout, maximize recovery with a small snack in a two-to-one ratio of grams of carbohydrates to protein prior to eating your meal. Examples include a few saltine or rice crackers and a glass of milk, or Greek yogurt with a few dried figs. Your pre- and post-workout nutrition is the best way to ensure that your hard work actually works!

RELATED: Are You Eating Enough? Here Are 5 Signs You Might Not Be

Mistake: Under-fueling

Fix: Smart Fueling

Water is likely your hydration beverage of choice, but for intense workouts lasting more than 45 to 60 minutes or long workouts more than 90 minutes, your body will perform best with the help of sport nutrition. Well-designed engineered sport nutrition products, like sport drinks, energy chews and gels, are formulated to provide your body with a precise amount of electrolytes and carbohydrates in the correct ratio when mixed with water. To maximize your fitness without compromising your health, it’s recommended to train your gut and taste buds to tolerate sport nutrition products while exercising by consuming about 25 to 50 calories, four to five ounces of fluid and 90 to 150 milligrams of sodium every 15 minutes of training during intense or long workouts.

RELATED: The Science And Mystery of Ultra Fueling(Opens in a new browser tab)