VO2 Max—the maximum rate of oxygen consumption measured during incremental exercise—is a primary indicator of cardiovascular fitness. Can you improve it just by walking?
The Intensity Threshold
For highly sedentary individuals, any walking will improve VO2 Max. However, for moderately fit individuals, casual walking (2-3 mph) will not provide enough cardiovascular stimulus. To drive VO2 Max adaptation via walking, you must manipulate grade (incline) or load (rucking).
The Treadmill Protocol
Walking at 3.5 mph on a 10% to 15% incline will elevate the heart rate of most individuals into Zone 4 or Zone 5, providing a VO2 Max stimulus identical to running, but without the high-impact stress on the joints.
Sample Workout
- 10 min warmup (0% grade, 3 mph)
- 4 x 4 minutes at 12% grade, 3.5 mph
- 3 minutes active recovery (0% grade, 2.5 mph) between intervals