Heart Rate Zones Explained: Practical 2025 Guide for Runners & Gym Users
Training by heart rate is one of the easiest ways to make your workouts more effective. Instead of guessing whether your run, ride or gym session in the US, UK or anywhere else is “hard enough”, you can use clear numbers. Our Heart Rate Calculator shows you exactly which zone you are in and what benefit you are getting.
What Each Heart Rate Zone Means
Your personalised zones are based on your maximum heart rate, resting heart rate and fitness level. Here is a quick overview:
- Zone 1 – Recovery (50–60% HRR): very easy pace, perfect for warm-ups, cool-downs and active rest days.
- Zone 2 – Easy / Fat-Burning (60–70% HRR): gentle, conversational effort. This is the classic “easy run” or steady walk where your body learns to use fat as fuel.
- Zone 3 – Steady Cardio (70–80% HRR): still sustainable, but you notice your breathing. Great for longer runs, bike rides and treadmill sessions.
- Zone 4 – Threshold (80–90% HRR): hard but controlled. Used for tempo runs and intervals when you want to improve speed and race performance.
- Zone 5 – HIIT / Max Effort (90–100% HRR): short bursts, such as sprints, hill repeats and high-intensity interval training.
If your main goal is fat loss, combine regular Zone 2 sessions with a calorie deficit. Our BMR Calculator and Budget Calculator can help you plan both your calories and your monthly gym costs in one place.
Sample Weekly Plan Using Your Heart Rate Zones
Here is a simple example for a busy person training 4–5 days a week in the US or UK:
- 2 days: 30–45 minutes in Zone 2 (easy jog, brisk walk, light cycle)
- 1 day: 20–30 minutes with intervals in Zones 4–5 (for example 6 × 1-minute hard / 1-minute easy)
- 1–2 days: mixed cardio or sports in Zones 2–3
- 1–2 days: rest or gentle walking in Zone 1
You can combine this with strength training and track your progress by repeating a similar workout at the same heart rate and watching your pace get faster over time.
When to Talk to a Doctor
Heart rate training is safe for most healthy adults. If you have a known heart condition, are on cardiac medication, or notice chest pain, dizziness or unusual shortness of breath, speak with your doctor before pushing into the higher zones. The calculator is a helpful training tool but it does not replace personalised medical advice.
Ready to fine-tune your training? Start with this Heart Rate Calculator, then check your Age Calculator and Percentage Calculator to quickly convert training percentages, discount offers on fitness gadgets, and more.