Heart Rate Zones for Weight Loss — Fat Burn Zone Calculator
The 'fat burn zone' myth misleads many. Higher intensity zones burn more total calories and more total fat — even though the percentage from fat is lower.
How It Works
Total calorie burn matters more than fuel source. A 30-minute Zone 4 workout burns more fat than a 30-minute Zone 2 session.
Zone 2 (60-70%) is still valuable for longer sessions (60+ minutes) where you can sustain the effort for more total calories.
Zone 3-4 (70-90%) maximizes calorie burn per minute — ideal for time-efficient 30-45 minute workouts.
Combine 2-3 Zone 3-4 sessions with 1-2 long Zone 2 sessions per week for optimal weight loss and fitness.
Frequently Asked Questions
Is Zone 2 really the best for fat burning?
Zone 2 burns the highest PERCENTAGE from fat (~60%), but Zone 4 burns more TOTAL fat because calorie burn is 2-3x higher. For weight loss, total calories matter more than fuel source.
How long should I exercise for weight loss?
Aim for 150-300 minutes/week of moderate-to-vigorous activity. Split between Zone 2 (longer, 45-60 min) and Zone 3-4 (shorter, 30 min) for best results.
Can I exercise too hard for weight loss?
Very high Zone 5 work is hard to sustain and causes significant fatigue. Stick primarily to Zones 2-4 for sustainable weight loss. Use Zone 5 sparingly for fitness.