This calculator helps you estimate your target heart rate zones for exercise, which is crucial for improving cardiovascular health and fitness effectively and safely.
function calculateHeartRateZones() {
var age = document.getElementById("age").value;
var maxHeartRateInput = document.getElementById("maxHeartRate").value;
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = ""; // Clear previous results
if (age === "" || isNaN(age) || age 0) {
maxHeartRate = parseFloat(maxHeartRateInput);
} else {
// Estimate Maximum Heart Rate using the general formula: 220 – age
maxHeartRate = 220 – parseFloat(age);
if (maxHeartRate <= 0) {
resultDiv.innerHTML = "Age entered is too high to calculate heart rate.";
return;
}
}
// Target Heart Rate Zones
// Moderate Intensity Zone: 50% to 70% of Max Heart Rate
var moderateMin = maxHeartRate * 0.50;
var moderateMax = maxHeartRate * 0.70;
// Vigorous Intensity Zone: 70% to 85% of Max Heart Rate
var vigorousMin = maxHeartRate * 0.70;
var vigorousMax = maxHeartRate * 0.85;
// Display Results
var outputHTML = "