When the winter chill sets in or the air quality drops due to smog, many people turn to treadmills for their running workouts. However, the correct way to run on a treadmill remains a mystery to many, and there are concerns about potential knee injuries. So, how does treadmill running compare to outdoor running, and what should you keep in mind to avoid injury?

Treadmill vs. Outdoor Running

In broad terms, running on a treadmill and running outdoors have similar effects on your body. Both can be done at the same heart rate and duration to effectively train your cardiovascular system.

However, the dynamics of treadmill running are different. The treadmill belt provides forward momentum, whereas outdoor running relies on your body’s gravitational inertia to propel you forward. On a treadmill, your body naturally generates a slight backward force to counteract the moving belt, requiring you to use a braking action that can disrupt the natural forward momentum of running outdoors.

When running outdoors, the ground exerts a forward reaction force on your foot as it lands. On a treadmill, this reaction force is reduced by the moving belt. To mitigate this, it’s advisable to reduce the treadmill speed and use a shorter stride with a higher cadence to maintain a more natural running form and reduce joint stress.

Key Data to Monitor on a Treadmill

During winter, some runners switch to treadmill running and notice a significant difference in their speed compared to outdoor running. GPS signals are weak indoors, making pace, distance, and speed data from your watch or phone inaccurate. However, data such as cadence and ground contact time remain reliable.

Therefore, focus less on pace and more on technique and perceived effort. Lower the treadmill speed and avoid matching outdoor running speeds directly. A speed range of 5-7 km/h with a slight incline of 1-3% can better simulate outdoor running conditions.

Correct Running Form on a Treadmill

Running form can differ between treadmill and outdoor running due to the moving surface of the treadmill. Common mistakes include landing with the pelvis behind the foot, leading to lower back strain and knee overuse.

Key points for proper treadmill running form include:

1. Avoid sudden speed increases: Keep a steady speed, generally around 8 km/h for basic fitness, with more experienced runners adjusting to 9-12 km/h. Excessive speed can cause you to lean forward excessively, increasing stress on the knees and lower back.

2. Look straight ahead, not down: Maintain an upright posture to avoid unnecessary strain.

3. Swing your elbows back: This activates your shoulder blades and promotes a balanced running form.

4. Listen to your body: Beginners don't need to maintain a constant speed. If you feel fatigued, it's okay to slow down or walk for a bit. Completing your target distance is the main goal.

Additionally, after finishing your run, gradually slow down the treadmill and walk for a few minutes to lower your heart rate to below 120 bpm and normalize your breathing before stepping off. Immediately stopping or lying down can cause dizziness or fainting.