Nutrition for Gym: Beginner's Guide

The essential fundamentals of calories, macros, and TDEE for building muscle and losing fat.

5 min read
January 15, 2026

Quick answer: To build muscle, eat 200-300 calories above your TDEE with 1.6-2.2g protein per kg. To lose fat, create a 500 calorie deficit. Use our free calculators below to find your exact numbers.

Nutrition accounts for at least 50% of your gym results. You can train perfectly, but without proper nutrition, muscles won't grow and fat won't budge.

The 3 Numbers You Need to Know

You don't need to be a nutrition expert. Everything comes down to three fundamental concepts:

TDEE

Total calories you burn per day. It's your starting point for any goal.

Macros

Protein, carbs, and fat. The distribution matters, especially protein.

Surplus/Deficit

Eat above TDEE to bulk, below to cut. Simple but fundamental.

In-Depth Guides

We've created detailed guides for each aspect of fitness nutrition. Each guide includes a free calculator to find your exact numbers.

Calculate Your TDEE for Free

Use our TDEE calculator to find your daily calories in under 30 seconds.

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Calories by Goal

GoalCalories vs TDEEExpected Result
Lean Bulk+200-300 kcal0.5-1kg/month muscle
Aggressive Bulk+500+ kcalMore muscle + fat
Maintenance= TDEEWeight stable
Slow Cut-300-500 kcal0.3-0.5kg/week fat
Aggressive Cut-750-1000 kcal0.7-1kg/week (muscle risk)

How Much Protein Do You Need?

Research is clear: 1.6-2.2g of protein per kg of bodyweight is the optimal range for muscle growth. Going higher doesn't provide additional benefits for most people.

Practical Example:

If you weigh 75kg: 75 × 1.8 = 135g protein per day. Split across 4-5 meals for optimal absorption (27-34g per meal).

Arvo Optimizes Based on Your Nutrition

Arvo automatically adjusts training volume and intensity based on your nutritional phase - bulk, maintenance, or cut - to maximize results.

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Common Mistakes to Avoid

❌ Avoid

  • • Too aggressive deficit (>1000 kcal)
  • • Insufficient protein while cutting
  • • Endless bulk without cut phases
  • • Changing goals every 2 weeks

✓ Best Practices

  • • Moderate deficit (500 kcal max)
  • • Increase protein to 2.2g/kg when cutting
  • • 8-16 week cycles per phase
  • • Track weekly weight (average)

Frequently Asked Questions

How many calories do I need to build muscle?

To build muscle, eat 200-500 calories above your TDEE (Total Daily Energy Expenditure). A moderate surplus of 200-300 calories minimizes fat gain while providing enough energy for muscle growth. Calculate your TDEE first, then add 10-20% for a lean bulk.

How much protein do I need per day for muscle growth?

Research shows 1.6-2.2g of protein per kg of bodyweight (0.7-1g per lb) is optimal for muscle growth. For a 80kg person, that's 128-176g of protein daily. Going higher than 2.2g/kg doesn't provide additional benefits for most people.

What is TDEE and why does it matter?

TDEE (Total Daily Energy Expenditure) is the total calories you burn each day, including your basal metabolic rate plus activity. It's the foundation of any nutrition plan - eat below TDEE to lose fat, at TDEE to maintain, or above TDEE to build muscle.

Should I track macros or just calories?

For building muscle, tracking at least protein is essential. Full macro tracking (protein, carbs, fat) gives more control but isn't necessary for everyone. At minimum, hit your protein target (1.6-2.2g/kg) and stay within your calorie goal.