How Macronutrients Could Be Measured to Account For Muscle Building and Weight Loss

When it comes to building muscle or losing weight, most people focus on calories which ultimately impact your overall physique and muscle gain. When in a state of surplus calorie consumption it can result in more muscle weight gain or when undergoing a calorie deficit it can result in weight loss. But the true engine behind more significant body composition changes lies in the power of macronutrients. Macronutrients also known as (macros) include carbohydrates, proteins, and fats. Each macro plays a unique role in how our bodies function and adapt to fitness regimens. To make real progress with your body transformation process especially in muscle building and weight loss. It’s essential to measure and adjust your macros based on your bodyweight, fitness goals, and your Total Daily Energy Expenditure (TDEE).

Understanding the Macronutrients

1. Protein

• Function: Supports muscle repair and growth.
• Calories per gram: 4 kcal
• Essential for: Muscle building, recovery, and maintaining lean mass during fat loss.

2. Carbohydrates

• Function: Primary energy source for high-intensity training.
• Calories per gram: 4 kcal
• Essential for: Fueling workouts, hormone regulation, and preventing muscle breakdown.

3. Fats

• Function: Hormone production, nutrient absorption, and long-term energy.
• Calories per gram: 9 kcal
• Essential for: Balanced health and metabolic function.

Step 1: Determine Your TDEE

TDEE (Total Daily Energy Expenditure) is the total number of calories you burn per day through your basal metabolism, daily activity, and exercise.

Use the Mifflin-St Jeor Equation to calculate Basal Metabolic Rate (BMR):

Men:
BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5

Women:
BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161

Then multiply BMR by an Activity Factor:

• Sedentary (1.2)
• Lightly Active (1.375)
• Moderately Active (1.55)
• Very Active (1.725)
• Super Active (1.9)

Example: (Joe – Muscle Building):

• Male, 25 years old, 80 kg, 180 cm, very active
• BMR = (10×80) + (6.25×180) – (5×25) + 5 = 800 + 1125 – 125 + 5 = 1805 kcal
• TDEE = 1805 × 1.725 = 3113 kcal/day

Step 2: Adjust for Fitness Goals

 Muscle Building:

Add 10–20% surplus to TDEE

• TDEE: 3113 + 15% = ~3580 kcal/day

Macro Breakdown Example (Client #1 – Bulking):

• Protein: 2.2g per kg bodyweight = 2.2 × 80 = 176g = 704 kcal
• Fats: 0.8g per kg = 0.8 × 80 = 64g = 576 kcal
• Carbs: Remaining calories = 3580 – (704 + 576) = 2300 kcal ÷ 4 = 575g

Daily Target:

• Protein: 176g
• Fats: 64g
• Carbs: 575g

 Weight Loss:

Subtract 15–25% from TDEE

• TDEE: 2500 – 20% = 2000 kcal/day

Macro Breakdown Example (Nancy – Cutting):

• Female, 65 kg, moderately active
• Protein: 2g/kg = 130g = 520 kcal
• Fats: 0.8g/kg = 52g = 468 kcal
• Carbs: Remaining = 2000 – (520 + 468) = 1012 ÷ 4 = 253g

Daily Target:

• Protein: 130g
• Fats: 52g
• Carbs: 253g

Macronutrient Ranges Based on Bodyweight

Goal	Protein (g/kg)	Fats (g/kg)	Carbs (Varies by calorie need)
Muscle Gain	1.6–2.4	0.8–1.2	Fill remaining calories
Fat Loss	2.0–2.4	0.8–1.0	Moderate to low carbs
Maintenance	1.4–2.0	0.8–1.0	Moderate

Tips for Measuring and Tracking Macros

1. Use a macro tracking app like MyFitnessPal or Cronometer.
2. Weigh your food using a digital scale.
3. Adjust every 2–4 weeks based on results (strength gains, weight changes, body composition).
4. Prioritize protein — especially important during a cut to maintain muscle.
5. Monitor biofeedback — energy levels, mood, sleep, digestion.

Final Thoughts

There’s no one-size-fits-all macro formula, but there is a science-based framework that can be customized. By calculating your TDEE and applying appropriate macronutrient ratios based on your goal, you create a plan that supports your physiology and performance standards.

Whether you’re helping clients or doing this for yourself, precision leads to progress. Once you start measuring macros according to these principles, results aren’t just likely but they’re going to become inevitable.

References:

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