.heart-rate-zones-calculator {
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#heart-rate-zones-result {
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Understanding Your Heart Rate Zones
Heart rate zones are ranges of your heart rate, expressed as a percentage of your maximum heart rate.
Training within specific heart rate zones can help you achieve different fitness goals, whether it's improving
endurance, burning fat, or increasing anaerobic capacity.
The most common method to estimate your maximum heart rate (MHR) is the age-based formula: 220 – Age.
However, this is an estimation, and your actual MHR might vary. For a more accurate assessment, consider a
stress test conducted by a healthcare professional.
Once your Maximum Heart Rate (MHR) and Resting Heart Rate (RHR) are known, you can calculate your Heart Rate Reserve (HRR).
HRR is the difference between your MHR and RHR. This reserve is what you use during exercise.
The formula is: HRR = MHR – RHR.
Heart rate zones are typically calculated using a percentage of your HRR, added to your RHR. The standard zones are:
- Zone 1 (Very Light): 50-60% of HRR. Used for recovery and active rest.
- Zone 2 (Light): 60-70% of HRR. Builds aerobic base and endurance.
- Zone 3 (Moderate): 70-80% of HRR. Improves aerobic fitness and efficiency.
- Zone 4 (Hard): 80-90% of HRR. Increases anaerobic threshold and speed.
- Zone 5 (Maximum): 90-100% of HRR. Improves VO2 max and maximal power.
By using this calculator, you can get a personalized estimate of your training zones, helping you to train smarter and more effectively towards your fitness objectives.
function calculateHeartRateZones() {
var ageInput = document.getElementById("age");
var restingHeartRateInput = document.getElementById("restingHeartRate");
var resultDiv = document.getElementById("heart-rate-zones-result");
var age = parseFloat(ageInput.value);
var restingHeartRate = parseFloat(restingHeartRateInput.value);
if (isNaN(age) || age 120) {
resultDiv.innerHTML = "Please enter a valid age between 1 and 120.";
return;
}
if (isNaN(restingHeartRate) || restingHeartRate = 220) {
resultDiv.innerHTML = "Please enter a valid resting heart rate (typically between 40 and 200 bpm).";
return;
}
// Estimate Maximum Heart Rate (MHR)
var maxHeartRate = 220 – age;
// Calculate Heart Rate Reserve (HRR)
var heartRateReserve = maxHeartRate – restingHeartRate;
// Calculate Zones
var zone1_min = restingHeartRate + (0.50 * heartRateReserve);
var zone1_max = restingHeartRate + (0.60 * heartRateReserve);
var zone2_min = restingHeartRate + (0.60 * heartRateReserve);
var zone2_max = restingHeartRate + (0.70 * heartRateReserve);
var zone3_min = restingHeartRate + (0.70 * heartRateReserve);
var zone3_max = restingHeartRate + (0.80 * heartRateReserve);
var zone4_min = restingHeartRate + (0.80 * heartRateReserve);
var zone4_max = restingHeartRate + (0.90 * heartRateReserve);
var zone5_min = restingHeartRate + (0.90 * heartRateReserve);
var zone5_max = maxHeartRate; // Zone 5 goes up to MHR
var resultHTML = "
";
resultHTML += "Estimated Maximum Heart Rate (MHR): " + maxHeartRate.toFixed(0) + " bpm";
resultHTML += "Heart Rate Reserve (HRR): " + heartRateReserve.toFixed(0) + " bpm";
resultHTML += "
" + zone1_min.toFixed(0) + " – " + zone1_max.toFixed(0) + " bpm (50-60% of HRR)";
resultHTML += "
" + zone2_min.toFixed(0) + " – " + zone2_max.toFixed(0) + " bpm (60-70% of HRR)";
resultHTML += "
" + zone3_min.toFixed(0) + " – " + zone3_max.toFixed(0) + " bpm (70-80% of HRR)";
resultHTML += "
" + zone4_min.toFixed(0) + " – " + zone4_max.toFixed(0) + " bpm (80-90% of HRR)";
resultHTML += "
" + zone5_min.toFixed(0) + " – " + zone5_max.toFixed(0) + " bpm (90-100% of HRR)";
resultDiv.innerHTML = resultHTML;
}