Professional Body Recomposition & Macro Planning Tool
Years
Please enter a valid age (15-90).
Feet
Inches
Pounds (lbs)
Please enter a positive weight.
Sedentary (Office job, little exercise)
Lightly Active (Exercise 1-3 days/week)
Moderately Active (Exercise 3-5 days/week)
Very Active (Exercise 6-7 days/week)
Extra Active (Physical job + training)
Be honest for best results.
Standard Recomp (Lose Fat/Gain Muscle) – Recommended
Maintenance (Focus on Muscle Gain)
Aggressive Cut (Prioritize Fat Loss)
Standard adjusts calories to -10% of TDEE.
Daily Calorie Target
2,450
Calories / day
Based on your TDEE of 2,722 calories.
Daily Macronutrient Targets
Protein (High)
180g
40%
Fats (Moderate)
65g
25%
Carbs (Remainder)
210g
35%
Visual breakdown of your daily macronutrients
Weekly Nutrient Schedule
Nutrient
Grams (g)
Calories
% of Total
*Protein is prioritized at approx 1g per lb of bodyweight to support muscle protein synthesis during caloric deficit.
What is a Lose Weight Gain Muscle Calculator?
A lose weight gain muscle calculator is a specialized tool designed to help individuals achieve "body recomposition." Unlike traditional diet calculators that focus solely on weight loss (caloric deficit) or weight gain (caloric surplus), this calculator identifies the specific nutritional "sweet spot" where your body can burn adipose tissue (fat) while synthesizing new muscle tissue.
This process is often called "recomping." It is highly effective for beginners, those returning from a break (muscle memory), and individuals with a higher body fat percentage. By optimizing protein intake and managing energy balance precisely, you avoid the "skinny fat" look that often results from aggressive dieting without resistance training.
Who is this for? This tool is ideal for anyone wanting to improve their physique by changing their body composition rather than just seeing a lower number on the scale.
Lose Weight Gain Muscle Formula & Math
To lose weight and gain muscle simultaneously, the math must balance energy needs. This calculator uses the Mifflin-St Jeor Equation to determine your Basal Metabolic Rate (BMR) and then applies activity multipliers and specific macronutrient ratios.
1. Determining Energy Expenditure (TDEE)
First, we calculate your BMR (energy burned at rest):
Men: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
Women: (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
We then multiply BMR by an Activity Factor to find your Total Daily Energy Expenditure (TDEE).
2. The Recomposition Variables
Unlike standard diets, the variable inputs for body recomposition prioritize protein over energy balance.
Variable
Meaning
Typical Target
Why it matters
Protein
Building blocks for muscle
1.0 – 1.2g per lb of bodyweight
Essential for Muscle Protein Synthesis (MPS) during a deficit.
Caloric Offset
Energy balance adjustment
-10% to -15% of TDEE
Small enough to fuel training, large enough to burn fat.
Fats
Hormonal support
0.3 – 0.4g per lb of bodyweight
Maintains testosterone and other hormones vital for recovery.
Key mathematical variables used in the lose weight gain muscle calculation logic.
Practical Examples (Real-World Use Cases)
Example 1: The "Skinny Fat" Beginner
Scenario: John is 30 years old, 180 lbs, 5'10", and works an office job but lifts weights 3 times a week.
TDEE Calculation: His maintenance is approximately 2,450 calories.
Calculator Output: To recomp, the calculator suggests 2,200 calories (-250 deficit).
Macros: 180g Protein (High), 70g Fat, 210g Carbs.
Result: Over 3 months, John might stay near 178 lbs, but his waist size decreases by 2 inches while his bench press increases, indicating fat loss and muscle gain.
Example 2: The Returning Athlete
Scenario: Sarah is 28, 150 lbs, 5'6″, and trains intensely 5 days a week (CrossFit).
TDEE Calculation: Her high activity puts her maintenance at 2,600 calories.
Calculator Output: She chooses "Maintenance" strategy. Target: 2,600 calories.
Macros: 150g Protein, 75g Fat, 330g Carbs.
Result: By eating at maintenance with high protein, she leverages "newbie gains" (or re-gains) to build muscle tissue using the energy provided by her diet, while her high metabolic rate slowly oxidizes fat stores.
How to Use This Lose Weight Gain Muscle Calculator
Enter Your Metrics: Input accurate age, height, weight, and gender.
Select Activity Level: Be honest. If you sit at a desk but workout for 1 hour, you are likely "Lightly Active" or "Moderately Active," not "Extra Active."
Choose Strategy:
Select Standard Recomp for a balance of fat loss and muscle growth.
Select Maintenance if you are already lean and want to focus purely on muscle.
Review Macros: The most critical number is the Protein result. You must hit this target daily to gain muscle while losing weight.
Track and Adjust: Use a food tracking app to match the calculator's output. If weight drops too fast (>1 lb/week), increase calories slightly.
Key Factors That Affect Body Recomposition
Several financial and biological "costs" impact your ability to lose weight and gain muscle simultaneously:
Protein Timing and Quality: It's not just about the total number. Consuming protein spread across 4-5 meals ensures a steady supply of amino acids for muscle repair.
Sleep Hygiene: Muscle is built while you sleep. Lack of sleep raises cortisol, which can catabolize (break down) muscle tissue and store fat.
Training Intensity: You cannot gain muscle without a stimulus. This calculator assumes you are performing resistance training (weights, calisthenics) close to failure.
Caloric "Budgeting": Think of your daily calories like a financial budget. You must "spend" them on high-nutrient foods (ROI) rather than empty sugars (waste) to see physical profit.
Hydration Status: Water is essential for transporting nutrients to muscle cells. Even slight dehydration can impair performance and metabolic rate.
Genetic Ceiling: Beginners can recomp easily. Advanced lifters will find it much harder to gain muscle in a deficit and may need to switch to dedicated "bulk" and "cut" cycles.
Frequently Asked Questions (FAQ)
Can I lose weight and gain muscle at the same time?
Yes, absolutely. This is called body recomposition. It is most effective for beginners, those with higher body fat, or those returning to training. It requires high protein intake and resistance training.
How much protein do I need?
Most research suggests between 0.8g to 1g of protein per pound of body weight (1.6g to 2.2g per kg) is optimal for muscle retention during a caloric deficit.
Should I do cardio?
Cardio is great for heart health and burning extra calories, but resistance training (lifting weights) is non-negotiable for the "gain muscle" part of the equation.
Why is the scale not moving?
In body recomposition, you are losing fat and gaining muscle. Since muscle is denser than fat, your weight might stay the same while your waist gets smaller. Use a mirror or tape measure instead of just the scale.
Is this calculator accurate for everyone?
It provides a statistical estimate. Individual metabolism varies. Use the results as a starting point and adjust based on your progress after 2-3 weeks.
What supplements should I take?
Supplements are not required, but Creatine Monohydrate and Whey Protein can help you hit your targets more easily.
Can I eat carbs?
Yes. Carbs fuel high-intensity training. This lose weight gain muscle calculator assigns carbs after protein and fat needs are met.
How long does recomposition take?
It is a slower process than a dedicated crash diet. Expect to see visual changes in 4-8 weeks, but significant transformation takes 6-12 months.
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