Calorie Burn Comparison
On average, a 155-lb person burns about 300-400 calories per 30 minutes on a treadmill (running at 6 mph) versus 210-310 calories on a stationary bike (moderate effort). However, the actual difference depends heavily on intensity — a hard cycling session can burn more than a leisurely jog.
Joint Impact and Injury Risk
Exercise bikes win here decisively. Cycling is low-impact and much gentler on knees, hips, and ankles. If you're overweight, recovering from injury, or have joint issues, a bike is the safer choice. Treadmills create 2-3x your bodyweight in impact force with each stride.
Space and Noise Considerations
Treadmills are typically larger and louder — plan for a dedicated area. Modern exercise bikes are compact and nearly silent, making them ideal for apartments. Some treadmills fold up, but they still need floor space when in use.
Our Recommendation
For pure weight loss, a treadmill has a slight edge in calorie burn. For sustainability and joint health, an exercise bike wins. The best machine is the one you'll actually use consistently. If you enjoy cycling or have joint concerns, go with a bike. If you love running, get a treadmill.