Hiit Training Heart Rate Calculator

HIIT Training Heart Rate Calculator

Measure this first thing in the morning for accuracy.

Your HIIT Training Profile

Max Heart Rate

0

Reserve (HRR)

0

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HIIT Work Interval (80% – 95% Intensity):

— to — BPM

Push your limits within this range during your "on" periods.

Active Recovery Zone (50% – 60% Intensity):

— to — BPM

Allow your heart rate to drop to this range between sprints.

function calculateHIITZones() { var age = parseFloat(document.getElementById('hiit_age').value); var rhr = parseFloat(document.getElementById('hiit_rhr').value); var resultsDiv = document.getElementById('hiit_results'); if (isNaN(age) || age 110) { alert('Please enter a valid age.'); return; } if (isNaN(rhr) || rhr 120) { alert('Please enter a valid resting heart rate (typical range: 40-100).'); return; } // Using Karvonen Formula for better accuracy in athletes // Max HR (Fox Formula) var mhr = 220 – age; // Heart Rate Reserve var hrr = mhr – rhr; // HIIT Work Zone: 80% to 95% of HRR + RHR var hiitLow = Math.round((hrr * 0.80) + rhr); var hiitHigh = Math.round((hrr * 0.95) + rhr); // Recovery Zone: 50% to 60% of HRR + RHR var recLow = Math.round((hrr * 0.50) + rhr); var recHigh = Math.round((hrr * 0.60) + rhr); document.getElementById('res_mhr').innerHTML = mhr + " BPM"; document.getElementById('res_hrr').innerHTML = hrr + " BPM"; document.getElementById('res_hiit_zone').innerText = hiitLow + " – " + hiitHigh + " BPM"; document.getElementById('res_recovery_zone').innerText = recLow + " – " + recHigh + " BPM"; resultsDiv.style.display = 'block'; resultsDiv.scrollIntoView({ behavior: 'smooth' }); }

Understanding Your HIIT Heart Rate Zones

High-Intensity Interval Training (HIIT) relies on alternating periods of short, intense anaerobic exercise with less-intense recovery periods. To maximize fat loss and cardiovascular gains, you must hit specific heart rate targets.

The Karvonen Method vs. Peak HR

Unlike simple calculators that only use 220 minus your age, this calculator uses the Karvonen Formula. By including your Resting Heart Rate (RHR), it accounts for your current fitness level. A lower RHR typically indicates a more efficient cardiovascular system, which adjusts your training zones accordingly.

How to Use These Numbers

• The Work Interval: During your sprint, burpees, or cycling burst, aim for the 80-95% range. You should find it difficult to speak during this phase.
• The Recovery Interval: Use active recovery (slow walk or light pedal). Do not sit still. Your heart rate should drop toward the 50-60% range before you start the next interval.
• Duration: Most HIIT sessions should last between 15 to 30 minutes. If you can go longer than 30 minutes, you likely aren't reaching the high-intensity zone calculated above.

Example Scenario: 30-Year-Old Athlete

If you are 30 years old with a resting heart rate of 60 BPM:

Metric	Value
Max Heart Rate	190 BPM
Work Target (HIIT)	164 – 184 BPM
Recovery Target	125 – 138 BPM

Disclaimer: Consult with a physician before starting any high-intensity exercise program. If you feel dizzy, nauseous, or experience chest pain, stop immediately.