How many calories do you aim to cut daily (diet + exercise)?
Your Weight Loss Running Plan
—
Running's contribution to calorie burn is estimated using METs (Metabolic Equivalents) and your weight. 1 kg of fat is roughly 7700 calories. Your total daily deficit dictates weight loss speed.
Projected Calorie Burn Over Time
Weekly Running Summary
Metric
Value
Unit
Weekly Running Distance
—
km
Estimated Weekly Calorie Burn from Running
—
kcal
Contribution to Daily Deficit
—
kcal
Estimated Weeks to Reach Goal
—
weeks
How Much Should I Run to Lose Weight Calculator
Understanding how much you need to run to achieve your weight loss goals is crucial for setting realistic expectations and creating an effective fitness plan. This calculator helps you quantify your running requirements based on your personal metrics and desired outcomes. Let's dive into the details of how running contributes to weight loss.
What is the How Much Should I Run to Lose Weight Calculator?
The How Much Should I Run to Lose Weight Calculator is a tool designed to estimate the amount of running you need to do weekly to support your weight loss objectives. It takes into account your current weight, your target weight loss, your running frequency, your average pace, and your desired daily calorie deficit. This calculator provides insights into the distance you should aim for and the calories you can expect to burn, helping you bridge the gap between your current state and your fitness goals. It's essential for individuals who are incorporating running into their weight loss strategy, whether they are beginners or experienced runners.
Who should use it? Anyone looking to lose weight who plans to use running as a primary or supplementary method of calorie expenditure. This includes individuals trying to create a calorie deficit through exercise, track their progress, and ensure their running routine is aligned with their weight loss targets.
Common misconceptions: A common misconception is that running alone will guarantee weight loss. While running is highly effective for burning calories, sustainable weight loss typically requires a combination of diet and exercise. Another myth is that you need to run extremely long distances from day one; this calculator aims to provide a balanced approach. We also often hear that more running always equals more weight loss, but this ignores the importance of recovery, nutrition, and the risk of injury if done unsafely.
How Much Should I Run to Lose Weight Calculator Formula and Mathematical Explanation
The How Much Should I Run to Lose Weight Calculator uses a series of calculations to determine your running needs. The core principle is to estimate the calories burned through running and ensure this contributes meaningfully to your overall calorie deficit.
Step-by-Step Derivation:
Calculate Calories Burned Per Kilometer: This is often estimated using the formula: `Calories Burned ≈ Weight (kg) * 1.036` (this is a common approximation, though MET values are more precise). A more refined method involves METs. Running at a 5.5 min/km pace is roughly equivalent to a MET value of 10. This means you burn approximately 10 calories per kilogram of body weight per hour.
Calculate Kilometers Per Minute of Running: If your pace is 5.5 minutes per kilometer, you run `1 / 5.5` kilometers per minute.
Calculate Calories Burned Per Minute of Running: This combines steps 1 and 2. Using the MET approach: `Calories per minute = (MET value * Weight (kg) * 3.5) / 200`. For a MET of 10 and a 75kg person, this is `(10 * 75 * 3.5) / 200 = 13.125` calories per minute.
Calculate Total Weekly Kilometers Needed: We need to determine how much running is required to meet a portion of the daily calorie deficit. If you run 3 days a week, and your daily deficit is 500 kcal, you might aim for running to cover 300 kcal of that deficit on running days. `Total Weekly Calories to Burn from Running = Desired Daily Calorie Deficit * 7 days`. However, we also need to consider the weight loss goal. To lose 1 kg of fat, you need a deficit of approximately 7700 calories. `Total Calorie Deficit Needed = Weight Loss Goal (kg) * 7700`. The calculator focuses on the *weekly running contribution* to a *sustainable* daily deficit. If we target covering a portion of the daily deficit (e.g., 300-400 kcal on running days) with running, and factor in the number of running days, we can estimate the required weekly distance. A common approach is to calculate the total calories to burn from running per week needed to support the target daily deficit: `Weekly Running Calorie Burn Needed = (Desired Daily Calorie Deficit – Non-Running Calorie Burn Portion) * 7`. A simplified approach in the calculator assumes running covers a significant part of the daily deficit. Let's assume running needs to cover `X` calories per day. `Weekly Calories from Running = X * Running Frequency`. The calculator determines the distance required to burn these calories. `Calories per km = Calories per minute / Kilometers per minute`. `Weekly Distance (km) = Weekly Calories from Running / Calories per km`.
Estimate Time to Goal: `Total Weeks = Total Calorie Deficit Needed / (Desired Daily Calorie Deficit * 7 days)`. The calculator shows how running contributes.
Variable Explanations:
Variable
Meaning
Unit
Typical Range
Weight (kg)
Your current body weight.
kg
40 – 150+
Weight Loss Goal (kg)
The total amount of weight you aim to lose.
kg
1 – 20+
Running Frequency
Number of days per week you run.
days/week
1 – 7
Average Running Pace (min/km)
Your typical speed when running.
min/km
4.0 – 8.0
Desired Daily Calorie Deficit
The target difference between calories consumed and calories burned daily.
kcal/day
300 – 1000
Calories Burned Per Minute
Estimated energy expenditure while running.
kcal/min
Variable based on weight and pace
Weekly Running Distance
Total distance to cover running each week.
km
Variable based on inputs
Estimated Weekly Calorie Burn from Running
Total calories burned specifically from running activities per week.
kcal/week
Variable based on inputs
Time to Goal
Estimated duration to reach weight loss target.
weeks
Variable based on inputs
Practical Examples (Real-World Use Cases)
Example 1: Moderate Weight Loss Goal
Scenario: Sarah weighs 70 kg and wants to lose 5 kg. She can commit to running 3 days a week and maintains an average pace of 6.0 minutes per kilometer. She aims for a daily calorie deficit of 500 kcal, with running contributing significantly to this.
Inputs:
Weight: 70 kg
Weight Loss Goal: 5 kg
Running Frequency: 3 days/week
Average Pace: 6.0 min/km
Desired Daily Calorie Deficit: 500 kcal/day
Calculated Outputs (Illustrative):
Estimated Weekly Running Distance: ~20 km
Estimated Weekly Calorie Burn from Running: ~1200 kcal
Time to Goal: ~10 weeks (assuming the 500 kcal daily deficit is consistently met)
Interpretation: Sarah needs to run approximately 20 km spread across 3 days (about 6.7 km per run) to burn around 1200 kcal weekly. This running effort, combined with dietary adjustments to meet the remaining 200 kcal daily deficit, should help her lose 5 kg in about 10 weeks.
Example 2: Significant Weight Loss Goal with Higher Frequency
Scenario: Mark weighs 90 kg and aims to lose 15 kg. He's willing to run 5 days a week and averages a pace of 5.0 minutes per kilometer. He wants a substantial daily deficit of 750 kcal.
Inputs:
Weight: 90 kg
Weight Loss Goal: 15 kg
Running Frequency: 5 days/week
Average Pace: 5.0 min/km
Desired Daily Calorie Deficit: 750 kcal/day
Calculated Outputs (Illustrative):
Estimated Weekly Running Distance: ~45 km
Estimated Weekly Calorie Burn from Running: ~2500 kcal
Time to Goal: ~13.5 weeks (assuming the 750 kcal daily deficit is consistently met)
Interpretation: Mark needs to run about 45 km weekly across 5 days (9 km per run) to burn approximately 2500 kcal. This significant calorie burn from running, complemented by dietary control for the remaining 250 kcal daily deficit, puts him on track to lose 15 kg in roughly 13.5 weeks. This example highlights that higher frequency and intensity demand more commitment but can accelerate progress.
How to Use This How Much Should I Run to Lose Weight Calculator
Using the How Much Should I Run to Lose Weight Calculator is straightforward. Follow these steps to get personalized insights:
Enter Your Current Weight: Input your weight in kilograms.
Specify Your Weight Loss Goal: Enter the total amount of weight (in kg) you aim to lose.
Set Your Running Frequency: Indicate how many days per week you plan to run.
Input Your Average Pace: Provide your typical running speed in minutes per kilometer. A faster pace generally burns more calories in less time but can be more demanding.
Define Your Desired Daily Calorie Deficit: Enter your target daily calorie deficit. This is the difference between the calories you consume and the calories you burn through diet and exercise combined. A common recommendation for safe and sustainable weight loss is a deficit of 500-750 kcal per day.
Click 'Calculate Needs': The calculator will process your inputs and display your results.
How to read results:
Primary Result (Main Highlight): This shows the estimated total weekly running distance required to significantly contribute to your calorie deficit.
Intermediate Values: You'll see your estimated weekly calorie burn from running, and the calculated time it might take to reach your goal based on your total daily deficit.
Assumptions: This section clarifies the key estimations used, such as the calorie burn rate per kilometer and the total calorie equivalent of 1 kg of fat.
Decision-making guidance: Use these results as a guideline, not a rigid rule. If the calculated weekly distance seems too high, consider increasing your daily calorie deficit through diet or incorporating other forms of exercise. Conversely, if it feels too low, you might be able to increase your running volume or intensity safely. Always listen to your body and consult with a healthcare professional or certified trainer.
Key Factors That Affect How Much Should I Run to Lose Weight Calculator Results
Several factors influence the accuracy and effectiveness of your running plan for weight loss. Understanding these nuances is key:
Metabolic Rate: Individual metabolic rates vary. Factors like age, sex, muscle mass, and genetics influence how many calories your body burns at rest and during exercise. The calculator uses averages, so your actual burn might differ.
Dietary Intake: This is perhaps the most critical factor. You cannot outrun a bad diet. The calculator assumes you are managing your caloric intake to achieve the desired daily deficit. If your diet isn't aligned, running volume alone might not yield results.
Intensity vs. Duration: While pace affects calorie burn per minute, the total duration or distance covered is paramount for total calorie expenditure. This calculator focuses on distance based on average pace, but varying your runs (e.g., interval training) can boost metabolism differently.
Consistency and Adherence: The calculator provides a weekly target. Hitting this consistently is crucial. Missing runs or not maintaining the target distance will extend the time to reach your weight loss goal.
Body Composition Changes: As you lose fat and potentially gain muscle (especially if you incorporate strength training), your weight changes. This affects the calorie burn calculations, as heavier individuals burn more calories per kilometer. Your pace might also improve with fitness.
NEAT (Non-Exercise Activity Thermogenesis): This refers to calories burned from activities outside of planned exercise, like walking, fidgeting, and standing. If your overall activity level decreases outside of running, your total daily deficit might be less than planned.
Sleep and Stress: Poor sleep and high stress levels can negatively impact hormones related to appetite and metabolism (like cortisol and ghrelin), potentially hindering weight loss efforts even with a consistent running schedule.
Hydration and Nutrition Timing: Proper hydration and strategic nutrient timing (especially around runs) support performance and recovery, indirectly affecting your ability to consistently meet your running goals.
Frequently Asked Questions (FAQ)
Q1: Is running the only way to lose weight?
A1: No, running is a highly effective tool for burning calories and contributing to weight loss, but it's not the only way. A balanced approach usually involves a combination of dietary changes and various forms of physical activity, including strength training and cardio.
Q2: How many calories are in one kilogram of fat?
A2: One kilogram of body fat is approximately equivalent to 7700 calories. This is a standard benchmark used in weight loss calculations.
Q3: What if my running pace is faster or slower than the input?
A3: The calculator uses your average pace to estimate calorie burn. If your pace varies significantly, adjust the input accordingly or understand that the results are estimates. A faster pace burns more calories per minute but might allow you to run for a shorter duration. A slower pace burns fewer calories per minute but allows for longer runs.
Q4: Can I reach my weight loss goal just by running, without changing my diet?
A4: It's highly unlikely and generally not recommended. While running burns significant calories, achieving a consistent and sustainable calorie deficit often requires dietary adjustments. Relying solely on exercise can lead to excessive training demands and potential burnout.
Q5: How often should I run per week for weight loss?
A5: The calculator suggests a frequency based on your goals. However, for beginners, starting with 2-3 times per week and gradually increasing is often advised to prevent injury. Consistency is more important than extreme frequency.
Q6: What if I can't run the calculated distance?
A6: If the calculated distance is too challenging, break it down. Run shorter distances more frequently, or increase your daily calorie deficit through diet. Consider cross-training with activities like cycling or swimming, which also burn calories.
Q7: Does running build muscle and affect weight loss differently?
A7: Running is primarily an aerobic exercise that burns calories. While it can build some muscle endurance in the legs, it's not the most effective activity for significant muscle hypertrophy. Increased muscle mass can boost metabolism, but the primary impact of running on weight loss is through calorie expenditure.
Q8: How does this calculator handle different body compositions (e.g., more muscle, less fat)?
A8: The calculator primarily uses total body weight for its estimations. Individuals with higher muscle mass might burn slightly more calories during exercise due to muscle's higher metabolic activity. However, the fundamental principle of calorie deficit remains the same. For precise tracking, consider body composition analysis.
Calorie Deficit CalculatorDetermine your daily calorie target for weight loss by calculating your Total Daily Energy Expenditure (TDEE).
BMI CalculatorCalculate your Body Mass Index (BMI) to get a general idea of your weight status.
Walking for Weight Loss GuideDiscover how walking can contribute to your weight loss journey and how to maximize its benefits.
Running Pace CalculatorCalculate your running speed and convert between different units of pace and distance.
Hydration CalculatorEstimate your daily fluid needs based on activity level, climate, and personal factors.
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var mainResultDiv = document.getElementById("mainResult");
var weeklyRunningDistanceDiv = document.getElementById("weeklyRunningDistance");
var weeklyCalorieBurnDiv = document.getElementById("weeklyCalorieBurn");
var timeToGoalDiv = document.getElementById("timeToGoal");
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var tableDist = document.getElementById("tableDist");
var tableCalBurn = document.getElementById("tableCalBurn");
var tableDailyContrib = document.getElementById("tableDailyContrib");
var tableWeeks = document.getElementById("tableWeeks");
var chart = null;
var chartContext = null;
var chartData = {
labels: [],
datasets: [{
label: 'Calories Burned (Running)',
data: [],
borderColor: 'var(–primary-color)',
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tension: 0.1
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var initialValues = {
weightKg: 75,
weightLossGoalKg: 5,
runningFrequency: 3,
avgPaceMinPerKm: 5.5,
desiredCalorieDeficitPerDay: 500
};
// MET value for running at a moderate pace (approx. 5.0 mph or 8.0 km/h -> 12 min/mile or ~7.5 min/km)
// METs vary with speed. A pace of 5.5 min/km (approx 6.5 mph or 10.4 km/h) is closer to MET 12-13.
// Let's use a MET value around 12 for a 5.5 min/km pace as a reasonable approximation.
var MET_RUNNING = 12;
var CALORIES_PER_KG_PER_HOUR_MET = 3.5; // Base for MET calculation
var CALORIES_PER_KG_PER_KM_APPROX = 1.036; // Simpler approximation often used
var KG_OF_FAT_TO_CALORIES = 7700;
function validateInput(inputElement, errorElement, min, max) {
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function calculateRunningNeeds() {
// Clear previous errors
weightKgError.style.display = "none";
weightLossGoalKgError.style.display = "none";
runningFrequencyError.style.display = "none";
avgPaceMinPerKmError.style.display = "none";
desiredCalorieDeficitPerDayError.style.display = "none";
// Validate inputs
var isValidWeightKg = validateInput(weightKgInput, weightKgError, null, null);
var isValidWeightLossGoalKg = validateInput(weightLossGoalKgInput, weightLossGoalKgError, null, null);
var isValidRunningFrequency = validateInput(runningFrequencyInput, runningFrequencyError, 1, 7);
var isValidAvgPaceMinPerKm = validateInput(avgPaceMinPerKmInput, avgPaceMinPerKmError, 1, null);
var isValidDesiredCalorieDeficitPerDay = validateInput(desiredCalorieDeficitPerDayInput, desiredCalorieDeficitPerDayError, 100, null);
if (!isValidWeightKg || !isValidWeightLossGoalKg || !isValidRunningFrequency || !isValidAvgPaceMinPerKm || !isValidDesiredCalorieDeficitPerDay) {
mainResultDiv.textContent = "Invalid Input";
weeklyRunningDistanceDiv.textContent = "—";
weeklyCalorieBurnDiv.textContent = "—";
timeToGoalDiv.textContent = "—";
assumptionsDiv.textContent = "Please correct the errors.";
updateChart([], [], []); // Clear chart
updateTable("–", "–", "–", "–");
return;
}
var weightKg = parseFloat(weightKgInput.value);
var weightLossGoalKg = parseFloat(weightLossGoalKgInput.value);
var runningFrequency = parseInt(runningFrequencyInput.value);
var avgPaceMinPerKm = parseFloat(avgPaceMinPerKmInput.value);
var desiredCalorieDeficitPerDay = parseFloat(desiredCalorieDeficitPerDayInput.value);
// — Calculations —
// 1. Calories burned per km (using MET and pace)
// Speed in km/h = 60 / avgPaceMinPerKm
var speedKmh = 60 / avgPaceMinPerKm;
// Calories burned per hour = MET * weight (kg) * 3.5 / 200 * 60 (minutes)
var caloriesPerHour = MET_RUNNING * weightKg * CALORIES_PER_KG_PER_HOUR_MET / 200 * 60;
// Calories burned per km = Calories burned per hour / speed (km/h)
var caloriesPerKm = caloriesPerHour / speedKmh;
// 2. Total calories to burn from running to meet a significant portion of the deficit
// Let's assume running covers, say, 60-70% of the daily deficit on running days.
// Or, calculate based on total weight loss goal and time.
// Total deficit needed for goal = weightLossGoalKg * KG_OF_FAT_TO_CALORIES
var totalDeficitNeeded = weightLossGoalKg * KG_OF_FAT_TO_CALORIES;
// Calculate weekly calories to burn from running to support the daily deficit target
// If daily deficit is 500, and running days are 3, then total weekly deficit target is 500*7 = 3500.
// Running might aim to cover a large portion of this. Let's say running needs to cover `X` kcal/week.
// A common approach is to make running contribute substantially.
// Let's calculate based on the weekly target deficit and how much running contributes.
// We can assume running should cover a portion of the goal deficit.
// A simpler approach: How many calories does running need to burn to contribute to the daily deficit?
// Let's assume running covers `contributionPercentage` of the `desiredCalorieDeficitPerDay`.
var contributionPercentage = 0.65; // Running contributes 65% of the daily deficit
var weeklyRunningCalorieTarget = (desiredCalorieDeficitPerDay * contributionPercentage) * runningFrequency;
// If the total deficit needed is huge, we might want to cap the weekly running contribution
// or ensure it's realistic. Let's stick to the daily deficit contribution first.
// 3. Weekly running distance required
var weeklyRunningDistance = weeklyRunningCalorieTarget / caloriesPerKm;
// 4. Estimated weekly calorie burn from running
var estimatedWeeklyCalorieBurnFromRunning = weeklyRunningDistance * caloriesPerKm;
// 5. Time to reach goal (based on total deficit needed and total daily deficit)
var estimatedWeeksToGoal = totalDeficitNeeded / (desiredCalorieDeficitPerDay * 7);
// — Display Results —
mainResultDiv.textContent = weeklyRunningDistance.toFixed(2) + " km";
weeklyRunningDistanceDiv.textContent = "Weekly Running Distance: " + weeklyRunningDistance.toFixed(2) + " km";
weeklyCalorieBurnDiv.textContent = "Estimated Weekly Calorie Burn from Running: " + estimatedWeeklyCalorieBurnFromRunning.toFixed(0) + " kcal";
timeToGoalDiv.textContent = "Estimated Weeks to Reach Goal (based on " + desiredCalorieDeficitPerDay + " kcal/day deficit): " + estimatedWeeksToGoal.toFixed(1) + " weeks";
var assumptionsText = "Assumptions: Running at " + avgPaceMinPerKm + " min/km burns approx. " + caloriesPerKm.toFixed(2) + " kcal/km for a " + weightKg + "kg person. 1 kg fat = " + KG_OF_FAT_TO_CALORIES + " kcal. Running covers approx. " + (contributionPercentage * 100).toFixed(0) + "% of daily deficit target.";
assumptionsDiv.textContent = assumptionsText;
// — Update Table —
updateTable(
weeklyRunningDistance.toFixed(2),
estimatedWeeklyCalorieBurnFromRunning.toFixed(0),
(estimatedWeeklyCalorieBurnFromRunning / (desiredCalorieDeficitPerDay * 7) * 100).toFixed(1) + "%", // Percentage of weekly deficit covered by running
estimatedWeeksToGoal.toFixed(1)
);
// — Update Chart —
updateChart(weightKg, avgPaceMinPerKm, runningFrequency, desiredCalorieDeficitPerDay, estimatedWeeksToGoal);
}
function updateTable(distance, calorieBurn, dailyContribPercentage, weeks) {
tableDist.textContent = distance;
tableCalBurn.textContent = calorieBurn;
tableDailyContrib.textContent = dailyContribPercentage;
tableWeeks.textContent = weeks;
}
function updateChart(weight, pace, frequency, dailyDeficit, totalWeeks) {
var canvas = document.getElementById('calorieBurnChart');
if (!canvas) return;
chartContext = canvas.getContext('2d');
// Clear previous chart if it exists
if (chart) {
chart.destroy();
}
// Prepare data for the chart
var labels = [];
var runningBurnData = [];
var totalDeficitData = [];
var currentKg = parseFloat(weightKgInput.value);
var currentPace = parseFloat(avgPaceMinPerKmInput.value);
var currentFrequency = parseInt(runningFrequencyInput.value);
var currentDailyDeficit = parseFloat(desiredCalorieDeficitPerDayInput.value);
var currentWeightLossGoal = parseFloat(weightLossGoalKgInput.value);
var MET_RUNNING = 12; // Approximate MET for 5.5 min/km pace
var CALORIES_PER_KG_PER_HOUR_MET = 3.5;
var speedKmh = 60 / currentPace;
var caloriesPerHour = MET_RUNNING * currentKg * CALORIES_PER_KG_PER_HOUR_MET / 200 * 60;
var caloriesPerKm = caloriesPerHour / speedKmh;
var contributionPercentage = 0.65;
var weeklyRunningCalorieTarget = (currentDailyDeficit * contributionPercentage) * currentFrequency;
var weeklyRunningDistance = weeklyRunningCalorieTarget / caloriesPerKm;
var estimatedWeeklyCalorieBurnFromRunning = weeklyRunningDistance * caloriesPerKm;
var totalDeficitNeeded = currentWeightLossGoal * KG_OF_FAT_TO_CALORIES;
var estimatedWeeksToGoal = totalDeficitNeeded / (currentDailyDeficit * 7);
var numWeeksToShow = Math.min(Math.max(5, Math.ceil(estimatedWeeksToGoal)), 20); // Show up to 20 weeks, min 5
for (var i = 1; i <= numWeeksToShow; i++) {
labels.push('Week ' + i);
var weekWeight = currentKg – (estimatedWeeksToGoal / numWeeksToShow) * i * (currentWeightLossGoal/estimatedWeeksToGoal); // Approximate weight reduction
if (weekWeight <= 0) weekWeight = currentKg; // Prevent negative weight for calculation
// Recalculate calories burned per km based on changing weight
var currentHourlyBurn = MET_RUNNING * weekWeight * CALORIES_PER_KG_PER_HOUR_MET / 200 * 60;
var currentCalPerKm = currentHourlyBurn / speedKmh;
// Running burn per week: assume distance is constant for simplicity or adjust based on weight loss.
// Let's assume the distance calculated initially is the target, but actual burn varies with weight.
// For simplicity, let's keep the target running distance constant and show burn.
// Alternatively, recalculate distance based on target calorie burn and new weight.
// For this chart, let's show the *potential* calorie burn if the target distance is maintained,
// or the *required* burn if weight changes.
// Option 1: Constant distance, variable burn
var burnThisWeek = weeklyRunningDistance * currentCalPerKm; // Burn based on new weight, same distance
var totalDeficitThisWeek = currentDailyDeficit * 7;
// Option 2: Constant calorie target, variable distance
// var targetWeeklyRunningCalories = (currentDailyDeficit * contributionPercentage) * currentFrequency;
// var requiredDistanceThisWeek = targetWeeklyRunningCalories / currentCalPerKm;
// var burnThisWeek = targetWeeklyRunningCalories; // The target itself
// var totalDeficitThisWeek = currentDailyDeficit * 7;
runningBurnData.push(burnThisWeek);
totalDeficitData.push(totalDeficitThisWeek);
}
chartData.labels = labels;
chartData.datasets[0].data = runningBurnData;
chartData.datasets[1].data = totalDeficitData;
chart = new Chart(chartContext, {
type: 'line',
data: chartData,
options: {
responsive: true,
maintainAspectRatio: false,
plugins: {
title: {
display: true,
text: 'Weekly Calorie Burn vs. Total Deficit',
font: {
size: 16
}
},
legend: {
position: 'top',
}
},
scales: {
x: {
title: {
display: true,
text: 'Timeframe'
}
},
y: {
title: {
display: true,
text: 'Calories (kcal)'
},
beginAtZero: true
}
}
}
});
}
function copyResults() {
var mainResult = mainResultDiv.textContent;
var weeklyDistance = weeklyRunningDistanceDiv.textContent;
var weeklyCalBurn = weeklyCalorieBurnDiv.textContent;
var timeToGoal = timeToGoalDiv.textContent;
var assumptions = assumptionsDiv.textContent;
var resultText = "— Running Weight Loss Plan —\n\n";
resultText += "Primary Result:\n" + mainResult + "\n\n";
resultText += weeklyDistance + "\n";
resultText += weeklyCalBurn + "\n";
resultText += timeToGoal + "\n\n";
resultText += assumptions + "\n\n";
resultText += "——————————–\n";
// Copy to clipboard
navigator.clipboard.writeText(resultText).then(function() {
// Success feedback – could change button text briefly
var copyButton = document.querySelector('.copy-btn');
var originalText = copyButton.textContent;
copyButton.textContent = 'Copied!';
setTimeout(function() {
copyButton.textContent = originalText;
}, 2000);
}).catch(function(err) {
console.error('Could not copy results: ', err);
alert('Failed to copy results. Please copy manually.');
});
}
function resetCalculator() {
weightKgInput.value = initialValues.weightKg;
weightLossGoalKgInput.value = initialValues.weightLossGoalKg;
runningFrequencyInput.value = initialValues.runningFrequency;
avgPaceMinPerKmInput.value = initialValues.avgPaceMinPerKm;
desiredCalorieDeficitPerDayInput.value = initialValues.desiredCalorieDeficitPerDay;
// Clear errors
weightKgError.textContent = ""; weightKgError.style.display = "none";
weightLossGoalKgError.textContent = ""; weightLossGoalKgError.style.display = "none";
runningFrequencyError.textContent = ""; runningFrequencyError.style.display = "none";
avgPaceMinPerKmError.textContent = ""; avgPaceMinPerKmError.style.display = "none";
desiredCalorieDeficitPerDayError.textContent = ""; desiredCalorieDeficitPerDayError.style.display = "none";
calculateRunningNeeds(); // Recalculate with defaults
}
// Initial calculation on page load
document.addEventListener('DOMContentLoaded', function() {
// Ensure inputs have default values before first calculation if not set in HTML
if (!weightKgInput.value) weightKgInput.value = initialValues.weightKg;
if (!weightLossGoalKgInput.value) weightLossGoalKgInput.value = initialValues.weightLossGoalKg;
if (!runningFrequencyInput.value) runningFrequencyInput.value = initialValues.runningFrequency;
if (!avgPaceMinPerKmInput.value) avgPaceMinPerKmInput.value = initialValues.avgPaceMinPerKm;
if (!desiredCalorieDeficitPerDayInput.value) desiredCalorieDeficitPerDayInput.value = initialValues.desiredCalorieDeficitPerDay;
calculateRunningNeeds();
// Initial chart update
updateChart();
});
// Add event listeners for real-time updates
weightKgInput.addEventListener('input', calculateRunningNeeds);
weightLossGoalKgInput.addEventListener('input', calculateRunningNeeds);
runningFrequencyInput.addEventListener('input', calculateRunningNeeds);
avgPaceMinPerKmInput.addEventListener('input', calculateRunningNeeds);
desiredCalorieDeficitPerDayInput.addEventListener('input', calculateRunningNeeds);
// Initialize chart data labels if they are empty
if (chartData.labels.length === 0) {
for (var i = 1; i <= 10; i++) { // Default to 10 weeks if no calculation yet
chartData.labels.push('Week ' + i);
}
}