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Find the Exercise Intensity for Your Target Heart Rate Zone

To train in a specific heart-rate zone, you need a matching exercise intensity. Using the Karvonen method, which accounts for your resting heart rate, a 35-year-old with a resting rate of 60 beats per minute has a max heart rate near 178 bpm and a heart-rate reserve of 118 bpm. For the cardio zone (60 to 70 percent of reserve) the target is about 131 to 143 bpm, an intensity of roughly 65 percent. The chart shows every zone from fat-burn to threshold so you can see where your chosen zone sits. These are population-based estimates, not a prescription.

Results

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VivMetric provides educational health-reference estimates only. These tools are not a medical diagnosis or professional advice, and results use general-population heuristics. Do not use them to start, stop, or change medication or treatment. Consult a qualified healthcare professional for personal medical decisions.

How It Works

Max heart rate uses the Tanaka formula, 208 - 0.7 x age, which is more accurate across ages than the old 220 - age rule. Heart-rate reserve (HRR) is max minus your resting rate. The Karvonen method sets a target as resting HR plus a percentage of that reserve, so two people of the same age get different targets if their resting rates differ. Each training zone is a percentage band of reserve: fat-burn 50 to 60 percent, cardio 60 to 70, aerobic 70 to 85, threshold 85 to 95. The tool computes the low and high beats per minute for your selected zone and reports the midpoint intensity. The chart plots all four zones so you can see the ladder. These are population estimates; individual maximums vary.

What Should You Do?

Use the target range as a live cue, not a rigid number. Wear a chest strap or optical sensor and aim to spend most of a session inside your chosen band, letting the chart guide which zone you are in. Beginners should start in fat-burn or cardio and build base fitness before aerobic or threshold work, which is demanding and needs recovery. A lower resting heart rate over weeks signals improving fitness, so re-enter your resting rate to update targets. Always warm up and cool down. This is educational reference, not training prescription; if you have heart disease, chest pain, or unexplained breathlessness, get cleared by a clinician before intensity training.

Frequently Asked Questions

Why use resting heart rate at all?

The Karvonen method scales intensity to your personal reserve, so a fit person and a beginner get different targets at the same age. It is more individualized than percent of max alone.

Is 220 minus age wrong?

It is a rough average. The Tanaka formula 208 - 0.7 x age tracks better across the lifespan and is used here.

What zone should a beginner use?

Fat-burn or cardio (50 to 70 percent of reserve) builds a safe base. Save threshold work for later, when fitness and recovery allow.

Can I train above the threshold zone?

Briefly, but sustained time near max is for trained athletes. The 85 to 95 percent band is already very hard.

Why does my watch show a different max?

Devices often estimate max differently. True max varies by individual; treat these numbers as estimates to train around.

Is this a medical clearance?

No. It is educational reference only. Consult a healthcare professional before starting intense exercise, especially with existing conditions.