| Category | BMI | For runners |
|---|
| Underweight |
Below 18.5 |
Risk of stress fractures & hormonal issues |
| Healthy weight |
18.5 – 24.9 |
Typical range for recreational runners |
| Overweight |
25 – 29.9 |
Higher joint load; build up gradually |
| Obese grade 1 |
30 – 34.9 |
Walk/run intervals are the smart start |
| Obese grade 2+ |
35+ |
Consult a doctor before starting to run |
BMI is a useful starting point but doesn't account for muscle mass. Highly trained runners may score "overweight" while being in excellent cardiovascular health. Use alongside body fat percentage for a fuller picture.