Safe Heart Rate When Exercising: A UK Guide by Age
Short answer: a widely used guide is that your maximum heart rate is roughly 220 minus your age, and moderate-intensity exercise sits at about 50–70% of that. If your heart rate climbs well above your moderate zone, feels pounding, or comes with dizziness or chest discomfort, ease off. Seeing the number live on your phone takes the guesswork out of "am I pushing too hard?".
This is general information, not medical advice, and a chest-strap heart rate monitor is a fitness device, not a medical device. If you have a heart condition or any concerns, speak to your GP before starting or changing exercise.
Safe heart rate when exercising: the essentials
- Estimated maximum heart rate is about 220 minus your age.
- Moderate intensity is roughly 50–70% of maximum; vigorous is about 70–85%.
- Warning signs — dizziness, chest pain, unusual breathlessness — mean stop and rest.
- A live reading on your phone makes it easy to stay in a comfortable, safe range.
What is a safe heart rate when exercising?
If a GP has advised more activity to help your blood pressure or weight, the phrase "moderate intensity" can be baffling. Heart rate turns it into something you can see. As a rule of thumb, subtract your age from 220 to estimate your maximum, then aim for a moderate band of about 50–70% of that when you are starting out. The table below gives a rough guide.
| Age | Estimated max (bpm) | Moderate 50–70% (bpm) |
|---|---|---|
| 40 | 180 | 90–126 |
| 50 | 170 | 85–119 |
| 55 | 165 | 83–116 |
| 60 | 160 | 80–112 |
These are estimates — real maximums vary from person to person and some medicines lower your heart rate — but they are a sensible starting point for staying in a comfortable range.
What does moderate intensity feel like?
The NHS suggests around 150 minutes of moderate activity a week. Moderate means your breathing is quicker and you feel warmer, but you can still talk. Walking uphill briskly, cycling gently or an aqua class all count. If you are walking up a hill and your heart is pounding at your throat, that has tipped into vigorous — slow down until you can speak in full sentences again.
When to ease off or stop
Numbers are useful, but symptoms come first. Stop and rest if you feel chest pain or tightness, become dizzy or light-headed, feel unusually breathless, or your heart is racing or skipping in a way that worries you. If these happen, seek medical advice. A live heart-rate reading simply gives you an early nudge to back off before you reach that point.
The easy way to see your heart rate
Fumbling for a pulse or waiting for a phone camera to guess your heart rate is frustrating. A chest strap sends a steady, live reading to a free app, shown in big clear numbers, so you always know where you are. Because the app can save your sessions, you can also show your GP a simple record of how your heart rate behaves during exercise at your next appointment. If you are brand new to this, our guide to a heart rate monitor without a watch shows how to get started with just your phone.
Seeing your live heart rate the easy way
The CardIQ heart rate monitor chest strap is built for exactly this. It is a dual-band strap that broadcasts on both ANT+ and Bluetooth, reads your heartbeat from an ECG-type electrode sensor rather than estimating it from the wrist, and is IP67-rated against sweat and rain. It pairs with Zwift, Garmin and Wahoo head units and a free phone app, runs on a common, user-replaceable CR2032 coin cell, and costs £29.33 inc. VAT (£24.44 ex. VAT). It ships the same day from our UK warehouse with free UK delivery, 30-day returns and a 12-month warranty with UK-based support, and is rated 4.8/5 across 200 reviews.
See your heart rate clearly while you move
View the CardIQ chest strap — £29.33Frequently asked questions
What is a safe heart rate when exercising?
A common guide is that your maximum is about 220 minus your age, with moderate exercise at roughly 50 to 70 percent of that. These are estimates, so use them as a starting range and let how you feel guide you.
How do I know if my exercise heart rate is too high?
If your heart rate climbs well above your moderate range and you feel pounding, dizzy, or unusually breathless, it is too high for that moment. Slow down until you can talk in full sentences, and stop and seek advice if symptoms continue.
Can I show my exercise heart rate to my GP?
Yes. A chest strap paired to a free phone app records your sessions, so you can show your GP a simple graph of how your heart rate behaves during exercise. It is a fitness device, not a medical device, but the trend is useful for a conversation.
Is a chest strap heart rate monitor easy to use?
It is designed to be. You dampen the strap, fasten it around your chest, open a free app, and your heart rate appears in large clear numbers. There are no small buttons or menus to learn.