Calculate your optimal weight for running based on height and biological sex.
Running Weight Calculator
Enter your height in centimeters.
Male
Female
Select your biological sex for adjusted calculations.
Sedentary (Little to no exercise)
Lightly Active (Light exercise/sports 1-3 days/week)
Moderately Active (Moderate exercise/sports 3-5 days/week)
Very Active (Hard exercise/sports 6-7 days/week)
Extra Active (Very hard exercise/sports & physical job)
Select your typical weekly physical activity.
Enter your estimated body fat percentage. Leave blank if unknown.
Your Running Weight Insights
— kg
Ideal Weight Range:— kg
Lean Body Mass:— kg
Fat Mass:— kg
BMI Category:—
Estimated Caloric Needs (TDEE):— kcal/day
How it's Calculated:
This calculator estimates your ideal running weight by first calculating your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation, then your Total Daily Energy Expenditure (TDEE) by factoring in your activity level. It also determines an ideal weight range and associated metrics based on your height and sex, often referencing healthy BMI ranges.
Chart showing ideal weight range based on height and sex.
Running Weight & Health Metrics
Metric
Value
Interpretation
Height
— cm
Your provided height.
Sex
—
Biological sex used for calculation.
Ideal Weight Range
— kg
The optimal weight range for running performance.
Target BMI
—
A healthy BMI often targeted for athletes.
Lean Body Mass
— kg
The weight of your body minus fat mass.
Fat Mass
— kg
The weight attributed to body fat.
TDEE
— kcal/day
Estimated Total Daily Energy Expenditure.
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Copy Your Results
Understanding Your Ideal Running Weight (kg)
{primary_keyword}: A Deep Dive into Optimal Performance
Achieving peak running performance involves more than just consistent training and proper nutrition. Your body composition and weight play a crucial role. Understanding your ideal running weight can help you optimize your efficiency, reduce injury risk, and enhance your overall running experience. This calculator and guide delve into what constitutes an ideal running weight, how it's determined, and what factors influence it.
What is Ideal Running Weight?
Your ideal running weight is not a single fixed number but rather a healthy weight range that allows for optimal biomechanics, energy efficiency, and reduced stress on your joints during running. It's a weight at which you feel strong, agile, and capable of performing at your best. For most runners, this typically falls within a healthy Body Mass Index (BMI) range, with an emphasis on a lower body fat percentage relative to muscle mass.
Who should use it:
Runners aiming to improve their race times or endurance.
Individuals looking to understand their body composition in relation to running.
Athletes seeking to maintain a weight that supports performance without compromising health.
Anyone curious about the interplay between weight and running efficiency.
Common misconceptions:
"Lighter is always faster": While excess weight can hinder performance, being too underweight can lead to muscle loss, reduced energy, and increased injury risk.
"There's one magic number": Ideal weight is highly individual, influenced by genetics, body frame, muscle mass, and sex.
"It's just about BMI": BMI is a useful screening tool, but it doesn't differentiate between muscle and fat, which is critical for runners.
{primary_keyword} Formula and Mathematical Explanation
Calculating an ideal running weight involves several steps, often starting with estimating basal metabolic rate (BMR) and then factoring in activity levels to determine total daily energy expenditure (TDEE). The ideal weight itself is often derived from healthy BMI ranges tailored for different heights and sexes.
1. Basal Metabolic Rate (BMR) Calculation:
We use the Mifflin-St Jeor equation, considered one of the most accurate for estimating resting energy expenditure:
For men: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) + 5
For women: BMR = (10 × weight in kg) + (6.25 × height in cm) – (5 × age in years) – 161
Note: Age is not directly used in this specific calculator but is a component of the standard BMR formula. For simplicity and focus on weight, we derive ideal weight ranges from height and sex, and calculate related metrics like Lean Body Mass and Fat Mass if body fat percentage is provided.
2. Total Daily Energy Expenditure (TDEE) Calculation:
TDEE = BMR × Activity Factor
Sedentary: BMR × 1.2
Lightly Active: BMR × 1.375
Moderately Active: BMR × 1.55
Very Active: BMR × 1.725
Extra Active: BMR × 1.9
3. Ideal Weight Range Calculation:
This calculator defines an ideal weight range by targeting a BMI between 18.5 and 24.9 (the healthy range), with a slight adjustment for athletes towards the middle or slightly lower end of this range, and considering sex-specific averages.
Weight (kg) = BMI × (Height in meters)²
We calculate a central target BMI (e.g., 22.5) and a range (e.g., 20-23) based on height and sex to provide a personalized ideal weight range.
4. Lean Body Mass (LBM) and Fat Mass Calculation:
If body fat percentage is provided:
Lean Body Mass (kg) = Current Weight (kg) × (1 – (Body Fat % / 100))
Fat Mass (kg) = Current Weight (kg) × (Body Fat % / 100)
Note: When calculating the *ideal* LBM and Fat Mass, we use the ideal weight derived from the BMI target.
Variables Table:
Variables Used in Calculations
Variable
Meaning
Unit
Typical Range / Values
Height
The vertical measurement from the sole of the foot to the crown of the head.
cm / meters
140 – 200 cm (example range)
Sex
Biological classification used for hormonal and physiological differences affecting BMR and body composition.
Categorical
Male, Female
Activity Level
The average amount of physical activity undertaken per week.
Categorical
Sedentary to Extra Active
Body Fat Percentage
The proportion of your total body weight that is made up of fat.
%
10% – 30% (example range for healthy adults)
Weight
The measure of the gravitational force on your body. Used for BMR and LBM/Fat Mass calculation.
kg
Variable based on input/calculation
BMI
Body Mass Index; a measure of body fat based on height and weight.
kg/m²
18.5 – 24.9 (Healthy range)
BMR
Basal Metabolic Rate; calories burned at rest.
kcal/day
Variable
TDEE
Total Daily Energy Expenditure; total calories burned per day.
kcal/day
Variable
Practical Examples (Real-World Use Cases)
Let's illustrate how the calculator works with realistic scenarios:
Example 1: A Competitive Female Runner
Inputs:
Height: 165 cm
Sex: Female
Activity Level: Very Active
Estimated Body Fat %: 18%
Calculator Output:
Ideal Weight Range: 54.5 kg – 59.0 kg
Main Result (Target): 56.7 kg (at BMI 20.8)
Lean Body Mass: 46.5 kg
Fat Mass: 10.2 kg
BMI Category: Healthy Weight
Estimated Caloric Needs (TDEE): ~2150 kcal/day
Interpretation: This runner is within a healthy weight range for her height and sex. Her body composition shows a good balance of lean mass and a healthy, performance-oriented body fat percentage. Her TDEE indicates the significant caloric intake required to fuel her high activity level.
Example 2: A Male Runner New to the Sport
Inputs:
Height: 180 cm
Sex: Male
Activity Level: Lightly Active
Estimated Body Fat %: 22%
Calculator Output:
Ideal Weight Range: 64.8 kg – 73.4 kg
Main Result (Target): 69.1 kg (at BMI 21.3)
Lean Body Mass: 53.9 kg
Fat Mass: 15.2 kg
BMI Category: Healthy Weight
Estimated Caloric Needs (TDEE): ~2100 kcal/day
Interpretation: This runner's current weight might be slightly above the ideal range for optimal running performance (we don't see his current weight input, but we infer based on the calculation). The results suggest a target weight that would place him in a healthy BMI. Focusing on reducing body fat while maintaining or increasing lean mass would likely improve his running efficiency and reduce joint impact. His TDEE suggests a moderate caloric need.
How to Use This Ideal Running Weight Calculator
Using the calculator is straightforward. Follow these steps to get your personalized running weight insights:
Enter Your Height: Input your height accurately in centimeters.
Select Biological Sex: Choose 'Male' or 'Female' based on your biological sex. This adjusts standard physiological calculations.
Choose Your Activity Level: Select the option that best describes your typical weekly exercise routine. Be honest to get the most accurate TDEE estimate.
Estimate Body Fat Percentage (Optional): If you know your approximate body fat percentage, enter it. This allows the calculator to estimate your lean body mass and fat mass, providing a more nuanced view than BMI alone. If unknown, leave it blank.
Calculate: Click the 'Calculate' button.
Review Results: The calculator will display your ideal weight range, target ideal weight, lean body mass, fat mass, BMI category, and estimated TDEE.
Interpret the Data:
Ideal Weight Range: Aim to be within this range for optimal running.
Lean Body Mass & Fat Mass: If you entered body fat, observe the balance. Runners often benefit from higher lean mass and lower fat mass.
BMI Category: Confirms if your target weight falls within the healthy range.
TDEE: Helps in understanding your daily caloric needs for training and recovery.
Use the Table and Chart: The table provides a detailed breakdown, and the chart offers a visual representation of your ideal weight in context.
Reset or Copy: Use the 'Reset' button to clear fields and start over, or 'Copy Results' to save or share your findings.
Decision-Making Guidance: Use these results as a guide, not a rigid prescription. If your current weight is significantly outside the ideal range, consult with a healthcare professional or a registered dietitian specializing in sports nutrition. Gradual, sustainable changes are key.
Key Factors That Affect Ideal Running Weight Results
Several factors influence what constitutes an ideal running weight for an individual:
Genetics and Body Frame: Bone density, natural muscle mass, and frame size (small, medium, large) significantly impact ideal weight. Some individuals naturally carry more muscle, which weighs more than fat.
Muscle Mass: Muscle is denser than fat. A highly muscular runner might weigh more but have a lower body fat percentage, making them perform better than a lighter individual with less muscle. Our calculator estimates Lean Body Mass to account for this.
Training Intensity and Volume: Higher training loads require more energy and can influence caloric needs (TDEE) and body composition. Very active individuals might need to consume more calories to maintain their weight and performance.
Age: Metabolic rate tends to decrease slightly with age. While not a primary input in this simplified calculator, age is a factor in BMR calculations and overall body composition changes over time.
Sex: Biological sex influences hormone levels, muscle mass distribution, and typical body fat percentages, leading to different ideal weight ranges and metabolic rates.
Nutrition: A balanced diet rich in protein supports muscle maintenance and growth, while adequate carbohydrates fuel performance. Poor nutrition can lead to muscle loss or inadequate energy stores, impacting running weight and ability.
Hydration: Water weight can fluctuate daily and impact perceived weight. Proper hydration is crucial for performance and overall health.
Overall Health and Medical Conditions: Certain medical conditions or medications can affect metabolism, weight, and energy levels. Always consult a doctor for personalized health advice.
Frequently Asked Questions (FAQ)
Q1: Is the ideal running weight the same for all runners?
A: No, ideal running weight is highly individual. Factors like genetics, body composition (muscle vs. fat), height, and sex play significant roles. The calculator provides a range and target based on general health guidelines.
Q2: Can I achieve my ideal running weight by just losing weight?
A: Not necessarily. The focus should be on achieving a healthy body composition – a good ratio of lean mass to fat mass. Simply losing weight might mean losing muscle, which can negatively impact performance and health.
Q3: How accurate is the TDEE calculation?
A: TDEE calculations are estimates. Individual metabolism can vary. Use the TDEE as a starting point for managing your caloric intake and adjust based on your actual energy levels and weight changes.
Q4: What if my current weight is very different from the ideal range?
A: If you are significantly above or below the calculated ideal weight range, consult a healthcare professional or a registered dietitian. They can help you create a safe and effective plan for reaching a healthier weight and body composition.
Q5: Does body fat percentage matter more than BMI for runners?
A: For runners, body composition (the ratio of lean mass to fat mass) is often considered more important than BMI alone. A high BMI could be due to high muscle mass, which is beneficial for running.
Q6: How quickly should I aim to reach my ideal running weight?
A: Aim for gradual, sustainable weight loss or gain (if needed) of 0.5-1 kg per week. Rapid changes can be detrimental to health and athletic performance.
Q7: Can I use this calculator if I'm training for a marathon?
A: Yes, absolutely. Marathon training demands high energy levels, and understanding your optimal weight and caloric needs is crucial for performance and recovery. Ensure your activity level reflects your intense training.
Q8: What are the risks of being too underweight for running?
A: Being too underweight can lead to fatigue, loss of muscle mass, compromised immune function, increased risk of stress fractures and other injuries, and hormonal imbalances (like amenorrhea in women).
Related Tools and Internal Resources
Explore these related tools and articles to further enhance your running journey and understanding of fitness:
Macronutrient Calculator: Determine the right balance of protein, carbs, and fats for your fitness goals.
Understanding your ideal running weight (kg) is a significant step towards unlocking your potential on the track or road. Combine this knowledge with consistent training, proper nutrition, and adequate rest for the best results.
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var heightM = heightCm / 100; // Convert height to meters for BMI calculation
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'sedentary': 1.2,
'lightlyActive': 1.375,
'moderatelyActive': 1.55,
'veryActive': 1.725,
'extraActive': 1.9
};
// Using a simplified approach for ideal weight based on healthy BMI ranges (18.5 – 24.9)
// We'll target a BMI of ~22.5 and provide a range.
var targetBmi = 22.5;
var lowerBmi = 18.5;
var upperBmi = 24.9;
// Calculate ideal weight range based on BMI
var idealWeightLower = lowerBmi * Math.pow(heightM, 2);
var idealWeightUpper = upperBmi * Math.pow(heightM, 2);
var targetIdealWeight = targetBmi * Math.pow(heightM, 2);
// Calculate approximate BMR and TDEE using a proxy weight (e.g., midpoint of ideal range)
// This is primarily for TDEE estimation, actual weight is needed for precise BMR.
// For simplicity, we'll use the target ideal weight to estimate BMR if no current weight is given.
var proxyWeightKg = targetIdealWeight; // Using target ideal weight for BMR calc for TDEE
var age = 30; // Assuming a default age for BMR calculation as it's not an input
var bmr;
if (sex === 'male') {
bmr = (10 * proxyWeightKg) + (6.25 * heightCm) – (5 * age) + 5;
} else { // female
bmr = (10 * proxyWeightKg) + (6.25 * heightCm) – (5 * age) – 161;
}
var tdee = bmr * activityFactors[activityLevel];
var leanBodyMass = null;
var fatMass = null;
var currentWeightForLbm = proxyWeightKg; // Use proxy weight if bodyFatPercentage is given
if (bodyFatPercentage !== null) {
leanBodyMass = currentWeightForLbm * (1 – (bodyFatPercentage / 100));
fatMass = currentWeightForLbm * (bodyFatPercentage / 100);
// Adjust ideal weight range if body fat is provided and indicates a need for recomposition
// For this calculator, we prioritize the BMI-based range as the primary target.
}
// Update results display
getElement('mainResult').textContent = targetIdealWeight.toFixed(1) + ' kg';
getElement('idealWeightRange').textContent = idealWeightLower.toFixed(1) + ' – ' + idealWeightUpper.toFixed(1) + ' kg';
getElement('leanBodyMass').textContent = leanBodyMass !== null ? leanBodyMass.toFixed(1) + ' kg' : '– kg';
getElement('fatMass').textContent = fatMass !== null ? fatMass.toFixed(1) + ' kg' : '– kg';
getElement('tdee').textContent = tdee.toFixed(0) + ' kcal/day';
// Update BMI Category
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getElement('tableTargetBmi').textContent = targetBmi.toFixed(1);
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getElement('tableFatMass').textContent = fatMass !== null ? fatMass.toFixed(1) + ' kg' : '– kg';
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return "Obese";
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getElement('mainResult').textContent = '– kg';
getElement('idealWeightRange').textContent = '– kg';
getElement('leanBodyMass').textContent = '– kg';
getElement('fatMass').textContent = '– kg';
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getElement('tdee').textContent = '– kcal/day';
getElement('tableHeight').textContent = '– cm';
getElement('tableSex').textContent = '–';
getElement('tableIdealWeightRange').textContent = '– kg';
getElement('tableTargetBmi').textContent = '–';
getElement('tableLeanBodyMass').textContent = '– kg';
getElement('tableFatMass').textContent = '– kg';
getElement('tableTdee').textContent = '– kcal/day';
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function resetCalculator() {
getElement('heightCm').value = '';
getElement('sex').value = 'male';
getElement('activityLevel').value = 'moderatelyActive';
getElement('bodyFatPercentage').value = '';
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var ctx = canvas.getContext('2d');
ctx.clearRect(0, 0, canvas.width, canvas.height);
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var canvas = getElement('weightVsBmiChart');
var ctx = canvas.getContext('2d');
canvas.width = canvas.offsetWidth; // Adjust canvas size to container
canvas.height = 300; // Fixed height for the chart
ctx.clearRect(0, 0, canvas.width, canvas.height); // Clear previous drawing
if (!heightCm || !idealWeightLower || !idealWeightUpper) return;
var heightM = heightCm / 100;
// Generate BMI values for the x-axis
var bmiValues = [];
for (var bmi = 15; bmi <= 35; bmi += 1) {
bmiValues.push(bmi);
}
// Calculate corresponding weights for these BMIs
var weightsForBmi = bmiValues.map(function(bmi) {
return bmi * Math.pow(heightM, 2);
});
// Define chart area and scales
var padding = 40;
var chartWidth = canvas.width – 2 * padding;
var chartHeight = canvas.height – 2 * padding;
// Determine Y-axis range (weight)
var maxWeight = Math.max.apply(null, weightsForBmi) * 1.1; // Add some buffer
var minWeight = Math.min.apply(null, weightsForBmi) * 0.9;
if (minWeight < 0) minWeight = 0;
var weightScale = chartHeight / (maxWeight – minWeight);
// Determine X-axis range (BMI)
var maxBmi = Math.max.apply(null, bmiValues);
var minBmi = Math.min.apply(null, bmiValues);
var bmiScale = chartWidth / (maxBmi – minBmi);
// Draw axes
ctx.strokeStyle = '#ccc';
ctx.lineWidth = 1;
// Y-axis (Weight)
ctx.beginPath();
ctx.moveTo(padding, padding);
ctx.lineTo(padding, canvas.height – padding);
ctx.stroke();
// X-axis (BMI)
ctx.beginPath();
ctx.moveTo(padding, canvas.height – padding);
ctx.lineTo(canvas.width – padding, canvas.height – padding);
ctx.stroke();
// Draw BMI labels on X-axis
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ctx.textAlign = 'center';
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});
// Draw Weight labels on Y-axis
ctx.textAlign = 'right';
var yAxisLabels = [Math.floor(minWeight), Math.floor(maxWeight)];
yAxisLabels.forEach(function(weight) {
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ctx.fillText(weight.toFixed(0) + ' kg', padding – 5, y);
});
// Draw Y-axis scale markings
var numMarkings = 5;
for (var i = 0; i <= numMarkings; i++) {
var weight = minWeight + (maxWeight – minWeight) * (i / numMarkings);
var y = canvas.height – padding – (weight – minWeight) * weightScale;
ctx.beginPath();
ctx.moveTo(padding – 3, y);
ctx.lineTo(padding, y);
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// Draw the main weight line based on BMI
ctx.strokeStyle = '#004a99';
ctx.lineWidth = 2;
ctx.beginPath();
weightsForBmi.forEach(function(weight, index) {
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var healthyWeightUpperY = canvas.height – padding – (idealWeightUpper – minWeight) * weightScale;
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ctx.strokeRect(startBmiX, healthyWeightUpperY, endBmiX – startBmiX, healthyWeightLowerY – healthyWeightUpperY);
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var targetWeightY = canvas.height – padding – (targetIdealWeight – minWeight) * weightScale;
ctx.beginPath();
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ctx.moveTo(padding, canvas.height – padding + 35);
ctx.lineTo(padding + 30, canvas.height – padding + 35);
ctx.stroke();
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ctx.fillText('Weight Trend', padding + 35, canvas.height – padding + 40);
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function copyResults() {
var heightCm = getElement('heightCm').value;
var sex = getElement('sex').value;
var activityLevel = getElement('activityLevel').value;
var bodyFatPercentage = getElement('bodyFatPercentage').value;
var mainResult = getElement('mainResult').textContent;
var idealWeightRange = getElement('idealWeightRange').textContent;
var leanBodyMass = getElement('leanBodyMass').textContent;
var fatMass = getElement('fatMass').textContent;
var bmiCategory = getElement('bmiCategory').textContent;
var tdee = getElement('tdee').textContent;
var copyText = "Ideal Running Weight Calculator Results:\n\n";
copyText += "— Inputs —\n";
copyText += "Height: " + (heightCm ? heightCm + " cm" : "–") + "\n";
copyText += "Sex: " + (sex ? sex.charAt(0).toUpperCase() + sex.slice(1) : "–") + "\n";
copyText += "Activity Level: " + (activityLevel ? activityLevel.replace(/([A-Z])/g, ' $1').trim() : "–") + "\n";
copyText += "Body Fat %: " + (bodyFatPercentage ? bodyFatPercentage + "%" : "–") + "\n\n";
copyText += "— Outputs —\n";
copyText += "Target Ideal Weight: " + mainResult + "\n";
copyText += "Ideal Weight Range: " + idealWeightRange + "\n";
copyText += "Lean Body Mass: " + leanBodyMass + "\n";
copyText += "Fat Mass: " + fatMass + "\n";
copyText += "BMI Category (at target weight): " + bmiCategory + "\n";
copyText += "Estimated TDEE: " + tdee + "\n\n";
copyText += "— Assumptions —\n";
copyText += "Calculations are estimates and may vary based on individual physiology.\n";
copyText += "Ideal weight range based on healthy BMI (18.5-24.9).\n";
copyText += "TDEE calculated using Mifflin-St Jeor equation with default age 30 and selected activity level.\n";
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textarea.select();
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try {
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var msg = successful ? 'Copied!' : 'Copy failed!';
// Optionally provide user feedback
alert(msg);
} catch (err) {
alert('Oops, unable to copy');
}
}
// Initialize calculator on page load
document.addEventListener('DOMContentLoaded', function() {
// Set default values or run initial calculation if defaults are set
getElement('heightCm').value = "175"; // Sensible default
getElement('sex').value = "male";
getElement('activityLevel').value = "moderatelyActive";
getElement('bodyFatPercentage').value = ""; // Leave blank by default
// Trigger calculation if default values are meaningful
if (getElement('heightCm').value) {
calculateRunningWeight();
}
});