Learn how to craft a weight gain meal plan for the underweight teenage athlete. It’s not just about high calorie foods!

I became interested in sports nutrition early. I was raising young athletes of my own, and seeing them in my private practice.

Mostly, they were coming in, looking for a weight gain meal plan.

Or how to lean out.

Or, even, some were showing up with eating disorders.

While it’s a common myth to believe all athletes are healthy, the truth is some struggle with their weight.

They can be overweight, or too thin.

In this article, I’m addressing underweight teenage athletes, from what causes low body weight to how to feed them for better weight gain.

Underweight Athletes: How to Gain Weight

Some parents and their athletes want to know how to gain weight in the healthiest of ways.

Although our nation tends to focus on the overweight aspect, the underweight young athlete may be just as troublesome.

An underweight athlete has a tougher time performing at his peak potential.

Normally, children and teens move through the natural ups and downs of growth and there’s little cause for worry.

But the growing athlete has a delicate balance to strike—matching energy needs for growth while covering the nutritional demands of sport at the same time.

For some young athletes, this is a continuous struggle.

Unmatched energy requirements may stem from the rigors of regular training, high energy needs associated with growth spurts, poor eating, or a poor diet.

If young athletes are losing weight and too thin they miss out on calories and nutrients.

As a result, their athletic performance, growth and overall health may suffer.

What is Normal Growth, and What’s Not?

Growth is calorie-hungry, as are certain sports, like running, swimming and rowing.

Normal growth relies on eating enough food to cover the energy and nutrient demands of sport and growth.

Normal growth for young athletes relies on eating enough food to cover the energy and nutrient demands of sport and growth. #foodisfuel #youngathletes #eatlikeachampion Click To Tweet

Normal growth is pretty steady.

You can tell is your athlete is growing normally by checking his body mass index (BMI).

It should be tracking steadily along an established and predictable curve.

Good Eating Habits to Encourage Weight Gain

For the school-age athlete, normal eating typically consists of three meals and 2-3 snacks per day.

The teen requires more calories for the adolescent growth spurt, especially males.

If your teen is in a regular sport with several hours of training most day of the week, he may need up to 4 meals and 1-2 snacks per day.

The Perils of Low Energy Intake

Skipping meals or snacks can lead to inadequate energy intake.

The same goes for dieting to lose weight or body fat.

Even more subtle: Failing to gain weight is a sign of under-eating and possibly poor nutrition.

Equally troublesome is when athletes push nutrients for athletic performance or body composition benefits, such as protein, to the exclusion of other sources of nutrition.

All of these dietary restrictions and practices are dangerous territory for your athlete’s health.

Helping Underweight Athletes Gain Weight

Feeding the underweight young athlete requires attention to food types, amounts, and timing of eating.

The best way to gain weight is not to “fatten up” the athlete if he is thin, but to match his energy needs for growth and sport, allowing for a healthy rate of weight gain and body composition to take shape.

Food is the fuel young athletes need to perform their best. Click To Tweet

Weight Gain Tips for Teenager Athletes

The best plan for gaining weight will address not only food choices but also the structure with which the athlete eats.

Here are 6 tips to help the teenage underweight athlete to gain weight:

1. Focus on Healthy, Balanced Meals for Healthy Weight Gain

A balanced, healthy meal plan is essential for helping underweight athletes gain weight.

Make sure to include a variety of all the food groups so that nutrients are present consistently throughout the day.

Include the following:

• Protein foods (eggs, lean meats, fish, beans, etc)
• Whole grains (whole grain breads, cereals, oatmeal, etc)
• Dairy (milk, yogurt, cheese), or fortified, non-dairy substitutes
• Fruit (apple, banana, berries)
• Vegetables (green beans, carrots, corn)
• Healthy fats (olive oil, nuts, avocado, peanut butter)

Aim for offering at least 4-5 of these different food groups at the main meals of the day.

Need some ideas?

Check out the nutrition booklet, Fuel Up! for Dinner recipe and Fast & Nutritious Breakfast Ideas for Athletes.

2. Elevate Snack Foods for Better Nutrition

With the above food groups in mind, offer 2 to 3 of them for snack foods.

For example, cereal, fruit and milk, or nut butter, crackers and raisins are examples of hearty, nutritious snacks.

I’ve got more ideas in my healthy snacks list for athletes here.

Don’t let snacks ruin your young athlete’s exercise.

Remember, create a power snack by adding a protein food, which will help satisfy your athlete’s appetite for longer periods of time than a carb-based snack by itself (ie, crackers).

3. Healthy Drinks Have a Purpose

Water is great for everyone, but the athlete who is underweight should try to drink beverages that offer both calories and nutrition.

Drinking milk or non-dairy substitutes, 100% juices, smoothies, and breakfast drinks can be an easy way to down some extra calories and nutrients.

4. Start a Bedtime Snack for Extra Calories

Eating a nutritious, healthy snack prior to bedtime can help the underweight athlete get extra calories that won’t be burned off while sleeping.

Try the following:

• Peanut butter toast
• Instant pudding made with whole milk
• A bowl of low sugar cereal
• A milkshake
• Trail mix
• Dinner leftovers

5. Use Fat to Build in More Calories

The addition of healthy fats to your underweight athlete’s usual foods can build in more calories.

It also eases the pressure and requirement to eat more, or huge portions of food.

These are some examples of adding extra calories to food:

• Add margarine, mayonnaise or avocado to sandwiches
• “Double-dress” cooked pasta (toss in olive oil, then top with butter or olive-oil soft spread)
• Sprinkle cheese on entrees.

6. Schedule Meals and Snacks to Improve Eating

Working with a schedule for meals and snacks will help your athlete eat in intervals, helping meet energy needs and optimize appetite.

A structured approach with eating ensures nutrition is on board, while helping build a rhythmic appetite for eating.

School-age athletes can eat every 3-4 hours, while teen athletes can schedule meals and snacks every 3-5 hours.

Remember, food is the fuel your young athlete needs to perform at his or her best.

Goals for Underweight Teens

When young athletes are underweight, they need to know how to gain weight.

The goal is to help them match their nutritional needs for growth and sport.

Many underweight young athletes feel better, have more energy, and even gain weight when their nutritional requirements are met.

Even better: They may improve their endurance, strength and stamina when they are at a healthy weight.

Need More Help with Feeding Young Athletes?

For more youth sports nutrition advice, check out my book, Eat Like a Champion: Performance Nutrition for Your Young Athlete.

Join our online program, Eat Like a Champion, which helps athletes and parents learn about the importance of sports nutrition and how to put it to use in your everyday life.

You may also want to read:

• 7 Tips for Feeding the Skinny Kid
• How to Get Taller: 7 Tips for Teens
• 13 Signs of the Teenage Growth Spurt
• Get the big picture and read The Young Athlete: Ultimate Guide to Nutrition.

HOW TO KEEP KIDS HYDRATED | Tips & Guidelines for Children (Even on Really Hot Days)

This article was originally published in June 2015 | Updated in October 2020.