Your maximum heart rate (MHR) is the highest number of times your heart can beat in one minute during maximal physical exertion. It's a crucial metric for understanding your exercise intensity zones. While the most common formula, 220 – age, is a rough estimate, more accurate formulas exist that take into account individual physiological differences.
The most widely accepted and scientifically validated formula for estimating maximum heart rate for most individuals is the Tanaka formula: 208 – (0.7 * age). This formula is generally considered more accurate across a wider range of ages than the simpler 220 – age formula.
function calculateMaxHeartRate() {
var age = document.getElementById("age").value;
var resultDiv = document.getElementById("result");
resultDiv.innerHTML = ""; // Clear previous results
// Validate input
if (age === "" || isNaN(age) || age 120) {
resultDiv.innerHTML = "Please enter a valid age between 1 and 120.";
return;
}
// Tanaka formula for Maximum Heart Rate
var maxHeartRate = 208 – (0.7 * age);
// Display the result
resultDiv.innerHTML = "Based on the Tanaka formula (208 – 0.7 * age), your estimated Maximum Heart Rate is: " + maxHeartRate.toFixed(0) + " bpm";
resultDiv.innerHTML += "It's important to remember that this is an estimation. Individual maximum heart rates can vary. For precise measurements, consider a supervised maximal exercise test conducted by a qualified professional.";
}
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