MAF Heart Rate Zones Calculator
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{
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"@type": "Question",
"name": "What is the MAF 180 Formula?",
"acceptedAnswer": {
"@type": "Answer",
"text": "The MAF (Maximum Aerobic Function) 180 Formula is a method developed by Dr. Phil Maffetone to determine your optimal maximum aerobic heart rate. It is calculated by subtracting your age from 180 and applying adjustments based on your health and fitness profile."
}
}, {
"@type": "Question",
"name": "Why should I train at my MAF heart rate?",
"acceptedAnswer": {
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"text": "Training at or below your MAF heart rate helps build a strong aerobic base, improves fat burning efficiency, reduces the risk of overtraining and injury, and can lead to faster race times with less physiological stress."
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}, {
"@type": "Question",
"name": "How often should I do a MAF test?",
"acceptedAnswer": {
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"text": "It is generally recommended to perform a MAF test (running at your MAF heart rate for a set distance/time) once a month to track your aerobic progress. As you become more efficient, your pace at the same heart rate should get faster."
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}
MAF Heart Rate Zones Calculator
Calculate your Maximum Aerobic Function heart rate using the 180 Formula.
Recovering from major illness, surgery, or on medication (-10)
Injured, regression in training, frequent colds/flu, or asthma (-5)
Consistent training (2+ years) without injury or problems (0)
Competitive athlete (2+ years), improving, injury-free (+5)
Max Aerobic Heart Rate
0 bpm
Target Training Zone
0 – 0 bpm
* This is your specific aerobic development zone. Do not exceed the upper limit during base training.
Understanding the MAF 180 Formula
The MAF (Maximum Aerobic Function) method, developed by Dr. Phil Maffetone, focuses on building a massive aerobic base. Unlike traditional "no pain, no gain" approaches, MAF training emphasizes low-intensity volume to teach your body to burn fat for fuel rather than sugar.
The Calculation Logic
The core of this method is finding your specific Maximum Aerobic Heart Rate. The formula starts simply: 180 minus your age. However, to be effective, this number must be adjusted based on your physiological history:
Subtract 10: If you are recovering from a major illness, surgery, hospital stay, or are on regular medication.
Subtract 5: If you have been inconsistent, are injured, have regressed in training, get more than two colds a year, or have allergies/asthma.
No Change (0): If you have been training consistently (at least 4 times a week) for up to two years without any of the problems listed above.
Add 5: If you have been training for more than two years without problems and have made measurable progress in competition.
Why Train Slow to Race Fast?
When you train at high intensities (anaerobic), your body relies primarily on glycogen (sugar) stores. These stores are limited. By training strictly within your MAF zone (Max Aerobic HR minus 10 beats), you optimize your aerobic system.
Benefits include:
Fat Adaptation: Teaching the body to utilize its virtually unlimited fat stores for energy.
Reduced Stress: Lower cortisol levels compared to high-intensity interval training (HIIT).
Injury Prevention: Less mechanical stress on muscles and tendons.
Longevity: Sustainable training that can be maintained for decades.
Implementing the Training
Once you have your number from the calculator above, strict adherence is key. During your base building phase, you should perform all your running, cycling, or swimming at a heart rate below your Max Aerobic number.
For example, if your calculated MAF HR is 145 bpm, your training zone is 135–145 bpm. If your heart rate spikes to 146 bpm on a hill, you must slow down or walk to bring it back into the zone. Over time, you will find yourself moving faster at the same heart rate—this is the sign of increased aerobic efficiency.
function calculateMAF() {
// Get input values
var ageInput = document.getElementById('mafAge');
var profileSelect = document.getElementById('mafProfile');
var age = parseFloat(ageInput.value);
var adjustment = parseFloat(profileSelect.value);
// Validation
if (isNaN(age) || age 120) {
alert("Please enter a valid age between 1 and 120.");
return;
}
// MAF Calculation Logic: 180 – Age + Adjustment
var maxAerobicHR = 180 – age + adjustment;
// The training zone is typically Max Aerobic HR – 10 to Max Aerobic HR
var lowerZoneLimit = maxAerobicHR – 10;
// Display Results
document.getElementById('mafMax').innerText = maxAerobicHR;
document.getElementById('mafZoneLow').innerText = lowerZoneLimit;
document.getElementById('mafZoneHigh').innerText = maxAerobicHR;
// Show result container
document.getElementById('mafResult').style.display = 'block';
}