Nutrition for Lean Muscle in Young Athletes

Nutrition for lean muscle helps you build strength and power without the bulk.

Lean muscle grows with the right training, fueling and recovery plan. Food is the foundation, and the results build over months. As a still-growing student-athlete, your goal is to fuel healthy development and athletic performance. Chasing a number on the scale or following a restrictive diet can work against that.

In this article, we’ll cover the basics of what goes into building lean muscle and suggestions of what to eat to get you started.

Important note: If you’re unsure how much or what to eat, work with a sports dietitian, pediatrician, or other qualified professional who understands the needs of growing athletes.

Key Takeaways

• Lean muscle comes from resistance training plus consistent fueling, not from eating as much as possible.

• Include protein at every meal and snack instead of saving most of it for dinner; research on adolescent athletes points to roughly 1.4 to 2 grams per kilogram (g/kg) per day.

• Carbohydrates fuel the training that builds muscle, and healthy fats support hormone production and vitamin absorption, so all three macronutrients (carbs, protein and fat) matter.

• Under-fueling is a common reason progress stalls in young athletes.

• Recovery (post-training meals, hydration, and sleep) is when muscle gets built.

What Lean Muscle Really Means

The most effective way to build muscle is through strength training and consistent, balanced eating. It helps you get stronger and move better in your sport. It usually means eating extra food on purpose to gain weight fast, and you don’t need to do that to build muscle. “Sleep also plays an important role in building muscle,” said Mollie Bartles, performance dietitian at IMG Academy. “Our body recovers when we sleep.”

It is most important to get enough fuel to build muscle and eat consistently. Rest, recovery is key too. .

Instead of judging progress by the mirror or the scale, look at what your body can do. Are you getting stronger? Recovering well? Feeling energized at practice? Those are better signs that your approach is working.

A 2025 review of adolescent athlete nutrition recommends focusing on performance, strength, and energy instead of weight or looks. Fueling for training and recovery, often called performance nutrition, is a solid way to guide your choices.

Nutrition for Lean Muscle Starts with Protein

Protein gives your body the building blocks it needs to repair and adapt after training, which makes it the anchor of any nutrition plan for lean muscle.

Try to include a protein source at each meal instead of saving most of it for dinner. Spreading protein throughout the day gives your body regular opportunities to use it for muscle repair and growth. “Make a list of your favorites and try to add a variety throughout the day,” said Max Dadswell, performance dietitian at IMG Academy.

The 2025 review of adolescent athlete nutrition suggests roughly 1.4 to 2 grams of protein per kilogram of body weight (g/kg) per day, spread across meals. That converts to about 0.64 to 0.91 grams of protein per pound of body weight. In a 150-pound student-athlete, that translates to around 96.0 to 136.5 grams of protein per day.

That’s useful research context, though your own needs may differ. Protein needs can vary from athlete to athlete, so a sports dietitian can help set a specific target.

Now that you have a general idea of how much protein is recommended for youth athletes, here’s a quick reference point for protein-rich foods that can help you meet your daily goals:

Note: These numbers are estimates, since protein content varies by brand, preparation, and serving size.

Remember, more protein isn't automatically better. A meta-analysis found that once athletes are already consuming enough protein, simply adding more doesn’t appear to provide additional performance benefits.

Carbohydrates: Fuel for Training That Helps Build Lean Muscle

When discussing lean muscle gains, protein gets plenty of attention, but it isn’t the whole story. Carbohydrates give you the energy for the resistance work and conditioning that help your muscles adapt and get stronger. If you skimp on carbs, you may show up to training already running on empty, making it harder to do the work that drives progress. “Carbs are the body’s number one fuel source,” said Bartles.

Carb choices include:

• Rice

• Oats

• Potatoes

• Whole-grain bread

• Fruit

• Starchy vegetables

The 2025 review of adolescent-athlete nutrition puts carbohydrate needs at roughly 6 to 10 g/kg per day, depending on training demands. For a 150-pound (68 kg) athlete, that’s roughly 410 to 680 grams of carbohydrates throughout the day.

Think of that range as part of a nutrition plan for muscle growth and performance, not a personal target. Remember, harder training days may call for more fuel.

Fats: Supporting Muscle Growth

Fat has a job in nutrition for lean muscle growth, too. It supports hormone production, including hormones involved in muscle development. And it helps your body absorb certain vitamins while providing longer-lasting energy between meals.

Anti-inflammatory fats choices include:

• Avocado

• Nuts and seeds

• Olive oil

• Nut butter

• Fatty fish such as salmon

Save the trans fats and heavily fried or highly processed foods for an occasional treat.

The same 2025 review of adolescent-athlete nutrition points to fat making up roughly 20 to 35% of daily calories. For a 150-pound (68 kg) athlete eating around 2,600 to 3,000 calories per day, that could mean roughly 60 to 115 grams of fat spread across meals.

Treat that as a ballpark example, not a number you need to hit exactly. Growing athletes have different energy needs, so a sports dietitian can help personalize a plan for you.

Sample Nutrition Plan for Lean Muscle Gain

A good nutrition plan for lean muscle should make balanced eating feel doable. The example below shows how protein, carbohydrates, and healthy fats can come together across a typical training day. “Your nutrition plan really depends on the athlete,” Molly said ... “It’s important to work with a registered dietitian to come up with the right plan for you.

Use it as a starting point for ideas, then customize your eating plan around your training, appetite, and schedule.

Spread balanced meals and snacks across the day, so no single meal has to do all the work.

Fuel the Training. Don’t Starve It.

You can't build muscle on empty. A common fueling mistake in young student-athletes is simply not eating enough to support training and a body that is still growing. “We’re always giving the analogy of our body is like a car. We wouldn’t want to drive on an empty tank so we wouldn’t want to train under-fueled,” said Dadswell “Especially if you’re growing. What happens when a car doesn’t have gas? It breaks down. For a body that means an increased risk of injury.” The 2025 review of teen athlete nutrition found that adolescent athletes across many sports often fall short of their energy needs. Carbohydrates provide the fuel for hard workouts, and enough total food gives your body what it needs to recover and build muscle.

Aim to eat enough to support your training and development, then add food gradually if your needs increase.

Chronic under-fueling can slow development and weaken bones. It also raises the risk of injury. If you’re unsure whether you’re eating enough, a dietitian can help you build a sports nutrition and fueling approach that supports both performance and healthy development.

Recovery Is Where Muscle Gets Built

Training gives your muscles a reason to adapt, but the actual repair and growth happen afterward. That makes recovery a key part of building lean muscle.

After a hard session, give your body what it needs to recover with a meal or snack that combines protein and carbohydrates. A chicken-and-rice bowl, eggs with toast and fruit, or Greek yogurt with oats and berries can all do the job.

Hydration matters, too. Drink water regularly throughout the day instead of trying to catch up after training, and keep meals consistent so your body has a steady supply of energy. And be sure to protect your sleep. For student-athletes, sleep supports recovery and normal growth.

If you’re training hard but not seeing progress, more effort may not be the missing piece. Sometimes your body simply needs a stronger recovery routine.

How Nutrient Needs Shift by Sport and Position

The basic approach to nutrition for building lean muscle stays the same across sports. Build meals around whole foods with enough carbs and protein to fuel your training. What changes is how much food your body needs, based on your size and the demands of your sport. “Everyone’s needs are going to be different depending on who you are, what position you are, what sport you play,” said Dadswell.

Because these demands vary so much, a sports dietitian can help you build a plan that fits your body and your sport.

How Long It Takes to Build Lean Muscle and What Stalls Progress

Building muscle is a slow-burn process. You may notice strength improving within a few weeks as your nervous system gets better at using the muscle you already have. Visible changes could take longer, often after at least a couple of months of consistent training, fueling, and sleep.

So, what gets in the way? The biggest culprit is usually not eating enough. If you’re short on total food or protein, your body has fewer available resources to support hard training, recovery, and growth. Chasing the scale instead of building good habits and cutting sleep short can slow you down, too. Supplements can’t make up for inconsistent meals.

Progress also isn’t perfectly linear. You might have a few strong weeks followed by a stretch where strength or muscle gain seems to slow down. That doesn’t necessarily mean something is wrong or that you need to overhaul your nutrition plan for lean muscle. Follow the basics: Eat consistently, train hard, recover well, and give it time.

How IMG Academy Helps Student-Athletes Build Lean Muscle

Building lean muscle takes more than adding protein to your meals. At IMG Academy, we connect fueling, training, and recovery to help student-athletes build habits that support steady gains. IMG Academy+ Essentials provides on-demand, expert-led nutrition guidance alongside training and mental performance content you can use anytime.

Because you’re still growing, your needs can shift as training demands and schedules change. IMG Academy+ Personal Coach offers live sessions with credentialed coaches who can help you adjust your fueling as part of your overall athletic development.

Conclusion: Build a Leaner, Stronger Frame

Lean muscle comes from training that challenges you, backed by nutrition and recovery that help your body respond. It’s a long-term process, so eat enough to support your training and growth, and give your body months to develop.

Ready for more support? Explore IMG Academy+ Essentials for on-demand nutrition and training content with progress tracking. For one-on-one guidance, IMG Academy+ Personal Coach connects you with credentialed experts for live virtual sessions on nutrition and mental performance.