To effectively burn fat and improve cardiovascular health, exercising within a specific heart rate zone is crucial. This calculator helps you determine your target heart rate zone for weight loss based on your age and resting heart rate.
Moderate (50-70% of Max Heart Rate)
Vigorous (70-85% of Max Heart Rate)
function calculateTargetHeartRate() {
var age = document.getElementById("age").value;
var restingHeartRate = document.getElementById("restingHeartRate").value;
var intensityLevel = document.getElementById("intensityLevel").value;
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = ""; // Clear previous results
// Validate inputs
if (isNaN(age) || age 120) {
resultDiv.innerHTML = "Please enter a valid age.";
return;
}
if (isNaN(restingHeartRate) || restingHeartRate 220) {
resultDiv.innerHTML = "Please enter a valid resting heart rate.";
return;
}
// 1. Calculate Maximum Heart Rate (MHR) using the Tanaka formula
var maxHeartRate = 208 – (0.7 * age);
// 2. Calculate Heart Rate Reserve (HRR)
var heartRateReserve = maxHeartRate – restingHeartRate;
var lowerBound = 0;
var upperBound = 0;
var intensityDescription = "";
// 3. Calculate Target Heart Rate Zone based on intensity level
if (intensityLevel === "moderate") {
lowerBound = (0.50 * heartRateReserve) + restingHeartRate;
upperBound = (0.70 * heartRateReserve) + restingHeartRate;
intensityDescription = "50-70% of your Maximum Heart Rate";
} else { // vigorous
lowerBound = (0.70 * heartRateReserve) + restingHeartRate;
upperBound = (0.85 * heartRateReserve) + restingHeartRate;
intensityDescription = "70-85% of your Maximum Heart Rate";
}
// Ensure bounds are not negative (though unlikely with valid inputs)
lowerBound = Math.max(0, lowerBound);
upperBound = Math.max(0, upperBound);
// Display the results
resultDiv.innerHTML = `