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Fitness Medium #heart-rate#zones#training

Heart Rate Zones

Zone 1-5 mapped to %HRmax, lactate, fuel mix, and training purpose.

A free, animated heart rate zones you can read here or embed on any website, from Scrollchart.

Heart Rate Zones

Heart Rate Training Zones5-zone system, %HRmax, blood lactate, fuel mix, and purpose per zone (HRmax = 180 bpm example)Zone%HRmaxBPMLactateFat%Carb%PurposeEffort1Z150-60%90-108<1 mmol/L85%F15%CActive recovery, warm-upVery easy2Z260-70%108-1261-2 mmol/L65%F35%CAerobic base building, fat oxidationConversational3Z370-80%126-1442-3 mmol/L40%F60%CTempo / steady-state enduranceModerate4Z480-90%144-1623-6 mmol/L15%F85%CThreshold, raise LT2Hard / labored5Z590-100%162-180+>6 mmol/L5%F95%CVO2max intervals, max speedMaximalFat oxidationCarbohydrate oxidation

Five horizontal bands stacked vertically: Zone 1 (50-60% HRmax) through Zone 5 (90-100%). Each band annotated with %HRmax, lactate, fuel mix (% fat vs carb), perceived effort, and typical session purpose.

Good for

  • Cardio programming articles
  • Beginner endurance content

Source & accuracy

This heart rate zones is an editorial illustration built to represent the concept accurately. Where it shows figures, they are typical or representative values chosen to make the relationship clear, not a single underlying dataset. The diagram and its explainer are reviewed and maintained centrally, and updated over time as understanding improves.

What the five heart rate zones represent

Heart rate zone models, commonly a five-zone scheme based on a percentage of maximum heart rate, divide training intensity into bands that loosely correspond to different physiological demands. Lower zones (1 and 2) sit below the first lactate threshold and emphasize fat oxidation and aerobic base building. Middle zones (3 and 4) move through the threshold region where lactate begins to accumulate. The top zone (5) covers near-maximal work that relies heavily on carbohydrate and cannot be sustained for long.

Each zone is associated with a training purpose, from easy recovery and aerobic development at the bottom to VO2 max and anaerobic stimulus at the top.

Why zone boundaries are approximate

Percentage-of-max formulas are estimates, and true physiological thresholds vary between individuals, so zones set by a generic formula can be off without lab or field testing. Heart rate also lags behind effort and drifts during long sessions, so it is an imperfect intensity gauge on its own.

This is general educational information about training intensity concepts, not personalized prescriptions. Estimating maximum heart rate by formula is rough, and anyone with cardiovascular concerns should consult a clinician before high-intensity training.

Embed this diagram

Add this animated heart rate zones to your own site. Copy one line of HTML, or use the embed builder for theme and sizing options.

Reference

What this is
A free, embeddable, animated heart rate zones for any website.
Who uses it
Fitness blogs, Sports blogs, Coaches & personal trainers, Wellness sites.
How to embed
Copy one line of HTML. No signup. No watermark. Works in WordPress, Webflow, Ghost, Substack, plain HTML.
File size
iframe embed, ~80 KB gzipped (loads on demand, does not block your page paint).
License
Free forever. Editorial explainer text included; updated centrally over time.
URL
scrollchart.com/diagram/cardio-zones

Embed format options

Copy the universal HTML snippet, the WordPress shortcode, or an iframe fallback - see the WordPress plugin page for details. Any format keeps the same Core Web Vitals profile and the same explainer text.

Embed snippet 
<div data-scrollchart="cardio-zones" data-scrollchart-v="1"></div>
<script src="https://scrollchart.com/embed.js" async></script>

By embedding, you acknowledge the diagram and explainer text are served from scrollchart.com and may be updated from time to time to reflect new research or to link to relevant sources within the explainer.

Frequently asked questions

Where can I get a free animated "Heart Rate Zones" for my website?
Scrollchart provides "Heart Rate Zones" as a free, embeddable animated diagram you can add to any website with one line of HTML. No signup is required and there is no watermark. The diagram and its explainer text are served from scrollchart.com, so the embed stays current without any maintenance on your end.
How do I embed a heart rate zones diagram in a health or wellness blog?
Copy the HTML snippet from the Scrollchart diagram page and paste it into any post or page in your CMS. It works in WordPress, Webflow, Ghost, Substack, and plain HTML without any plugin or account. The diagram renders as animated SVG directly in your page, so search engines can index the accompanying explainer text.
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