Nutrition & Fitness Calculator

Q: Is the 1RM estimate safe?

Yes, using sub-maximal testing (lifting a weight 3-8 times) and calculating 1RM is far safer than attempting a true one-rep maximum, especially without a spotter.

Q: How often should I test my 1RM?

It is recommended to test every 4-8 weeks to track progress. Doing it too frequently can stress the Central Nervous System (CNS).

Q: What is the Brzycki Formula?

It is one of the most accurate equations for predicting 1RM based on reps of a lighter weight. Note: Accuracy decreases as reps go above 10.

Q: What is a good running pace?

It depends entirely on distance and experience. A 5:00 min/km pace is competitive for a 5K, while 6:00-7:00 min/km is a common training pace for beginners.

Calculate

💡 Calculate your TDEE and optimal macro split for your goals.

How to use the Complete Guide to Nutrition & Macros

Calories are simply units of energy. Whether your goal is weight loss, muscle gain, or maintenance, the fundamental principle remains the same: Energy Balance. This calculator uses the Mifflin-St Jeor equation, widely considered the most accurate formula for estimating Calorie intake needs.

However, a number is just a starting point. Your actual metabolic rate can vary based on genetics, muscle mass, and even the "thermic effect" of the foods you eat (protein burns more calories to digest than fat). Use this estimate as a baseline and adjust based on your real-world progress.

🔥 TDEE Explained

Your Total Daily Energy Expenditure is the sum of:
• BMR: Calories burned at rest (coma state).
• NEAT: Non-exercise movement (fidgeting, walking).
• TEF: Digestion energy.
• EAT: Exercise Activity Thermogenesis.

📉 The Deficit Sweet Spot

For sustainable weight loss, a deficit of 300-500 calories below TDEE is recommended. This usually results in 0.5-1 lb of fat loss per week. Aggressive deficits (>1000) often lead to muscle loss and metabolic adaptation.

🥩 Macro Split

Calories aren't everything. Protein is critical for muscle retention during weight loss. A common split is 40% Carbs, 30% Protein, 30% Fat.

The Formula

TDEE = BMR × Activity Factor

Activity Levels Decoded

Sedentary: Desk job, little to no dedicated exercise. (BMR x 1.2)
Lightly Active: Light exercise 1-3 days/week. (BMR x 1.375)
Moderately Active: Moderate exercise 3-5 days/week. (BMR x 1.55)
Very Active: Hard exercise 6-7 days/week. (BMR x 1.725)

Common Questions

Should I count net carbs?

For weight loss, total carbs matter most. Net carbs (Carbs - Fiber) are specifically useful for those on a ketogenic diet to track blood glucose impact.

How accurate is TDEE?

TDEE is an estimate. It provides a starting point. If you aren't losing weight at the calculated deficit, adjust your calorie intake down by another 100-200 calories.

Does muscle burn more calories than fat?

Yes. Muscle tissue is metabolically active and burns ~6 calories per lb/day at rest, whereas fat burns only ~2 calories. Adding muscle increases your BMR.

How to use the Complete Guide to Hydration

Hydration is the unsung hero of performance and health. Water makes up about 60% of your body weight and is involved in every single metabolic process, from temperature regulation to nutrient transport. Even mild dehydration (1-2% body weight loss) can impair cognitive function and physical performance.

The "8 glasses a day" rule is a myth. Your needs depend heavily on your size, activity level, and climate. This calculator provides a personalized baseline to ensure you're functioning at your peak.

🧠 Cognitive Impact

Brain cells are highly sensitive to dehydration. Lack of water causes brain tissue to shrink, leading to headaches, lack of focus, and fatigue. Drinking water is often the fastest cure for an afternoon slump.

🏋️ Performance Booster

Muscle cells need water to contract. Dehydration reduces blood volume, making your heart work harder to pump oxygen. Proper hydration can improve endurance and reduce recovery time.

💧 Electrolytes

Water isn't enough if you're sweating heavily. You also lose sodium, potassium, and magnesium. If you're training hard, consider adding electrolytes to prevent hyponatremia (water intoxication).

The Formula

Water (L) = Weight (kg) × 0.035

Signs of Dehydration

Urine Color: Pale yellow corresponds to proper hydration. Dark amber means drink more. Clear means you might be over-hydrated.
Thirst: By the time you feel thirsty, you are already slightly dehydrated.
Dry Skin/Lips: Chronic dehydration often shows up on the skin first.

Common Questions

Does coffee count towards water intake?

Yes, but it is a mild diuretic. Water is still the best source of hydration. Moderated caffeine intake does not cause significant dehydration.

How much should I drink while exercising?

Aim for 200-300ml every 10-20 minutes during intense exercise. Weigh yourself before and after; drink 1.5L for every kg lost.

Is cold water better?

Cold water may absorb slightly faster and helps lower core body temperature during exercise, but room temperature water is just as hydrating for general use.

How to use the Complete Guide to 1RM & Strength

One-Rep Max (1RM) is the gold standard for measuring absolute strength. It represents the maximum weight you can lift for a single repetition with proper form. Knowing this number allows you to program your training effectively using percentage-based work.

Testing a true 1RM is taxing on the central nervous system and carries injury risk. This calculator uses the Brzycki Formula to estimate your 1RM based on sub-maximal lifts (e.g., 5 reps at a lower weight), allowing you to track progress safely.

📈 Training Zones

• Power: 85-95% of 1RM (1-3 reps).
• Strength: 75-85% of 1RM (3-6 reps).
• Hypertrophy (Size): 65-75% of 1RM (8-12 reps).
• Endurance: <60% of 1RM (15+ reps).

⚠️ Safety First

The accuracy of 1RM formulas decreases as reps increase. A 3-rep max calculation is far more accurate than a 15-rep max calculation. For best results, use a weight you can lift 3-5 times.

🛡️ Progressive Overload

To get stronger, you must gradually increase the stimulus. Use your estimated 1RM to re-calculate your working weights every 4-6 weeks.

The Formula

1RM = Weight × (36 / (37 - Reps))

The Big Three

1RM is most commonly tracked for the primary compound lifts:

Squat: The king of lower body exercises.
Bench Press: The standard for upper body pushing strength.
Deadlift: The ultimate test of total body pulling strength.

Common Questions

Is the 1RM estimate safe?

Yes, using sub-maximal testing (lifting a weight 3-8 times) and calculating 1RM is far safer than attempting a true one-rep maximum, especially without a spotter.

How often should I test my 1RM?

It is recommended to test every 4-8 weeks to track progress. Doing it too frequently can stress the Central Nervous System (CNS).

What is the Brzycki Formula?

It is one of the most accurate equations for predicting 1RM based on reps of a lighter weight. Note: Accuracy decreases as reps go above 10.

How to use the Complete Guide to Running Pace

Pace is the fundamental metric for runners, cyclists, and swimmers. It defines the speed of your endurance efforts in "Time per District" (e.g., minutes per mile). Unlike simple speed (mph), pace helps you micromanage your energy output over long distances.

Whether you're aiming for a sub-4-hour marathon or just trying to run your first 5K without walking, understanding your pace splits is key to race day strategy. Going out too fast ("banking time") is a common rookie mistake that usually ends in "hitting the wall."

🏃 Race Strategy

Negative Splits: Running the second half of a race faster than the first. This is the strategy used for almost every world record. It requires discipline to hold back early when adrenaline is high.

🏁 Common Milestones

• 5K: 3.1 miles.
• 10K: 6.2 miles.
• Half Marathon: 13.1 miles.
• Marathon: 26.2 miles.

🕐 Tempo Runs

Training at your "Lactate Threshold" pace (comfortably hard) helps your body clear lactate more efficiently, allowing you to run faster for longer.

The Formula

Pace = Time / Distance

Pace Conversion Cheatsheet

Target Time (5K)	Required Pace
20:00	6:26 /mile
25:00	8:03 /mile
30:00	9:39 /mile

Common Questions

What is a good running pace?

It depends entirely on distance and experience. A 5:00 min/km pace is competitive for a 5K, while 6:00-7:00 min/km is a common training pace for beginners.

How do I improve my pace?

Incorporate 'Tempo Runs' (comfortably hard effort) and Interval training into your weekly schedule to improve your VO2 max and running economy.

What is negative splitting?

Negative splitting means running the second half of a race faster than the first. It is the strategy used for almost every world record performance.

Nutrition & Fitness Calculator

Results

How to use the Complete Guide to Nutrition & Macros

🔥 TDEE Explained

📉 The Deficit Sweet Spot

🥩 Macro Split

The Formula

Activity Levels Decoded

Common Questions

How to use the Complete Guide to Hydration

🧠 Cognitive Impact

🏋️ Performance Booster

💧 Electrolytes

The Formula

Signs of Dehydration

Common Questions

How to use the Complete Guide to 1RM & Strength

📈 Training Zones

⚠️ Safety First

🛡️ Progressive Overload

The Formula

The Big Three

Common Questions

How to use the Complete Guide to Running Pace

🏃 Race Strategy

🏁 Common Milestones

🕐 Tempo Runs

The Formula

Pace Conversion Cheatsheet

Common Questions