Training on a Treadmill – The Right Way to Do It

For many runners, the treadmill is a necessary training partner. Whether it's due to poor weather, time constraints, safety concerns, or the simple convenience of training at home or in the gym, treadmills offer a reliable way to keep mileage ticking over. But like any tool, they have limitations.

Why Pace on a Treadmill is Misleading

One of the biggest mistakes runners make is treating treadmill pace as gospel. Unlike outdoor running, where pace reflects your actual energy cost of moving across terrain, treadmill pace is artificial. Factors like motor calibration, belt tension, flywheel mechanics, and even body weight change the "true" pace.

GPS doesn't work on a treadmill, so your watch relies on its internal accelerometer to estimate speed and distance. That estimate depends on your arm swing and cadence, which can shift during treadmill running compared to outdoors. Instead of fixating on pace, train by duration and RPE (Rate of Perceived Exertion).

Why Flat Treadmill Running Isn't Ideal

Running at 0% gradient on a treadmill doesn't mimic outdoor running for two main reasons:

1. Reduced Muscle Activation — On flat treadmills, your glutes switch off because the belt pulls your foot backward. Outdoors, you must actively extend your hip to drive forward, firing up the glutes for propulsion.
2. No True Toe-Off Push — The moving belt removes the need for a full push-off phase. This means your calves and posterior chain don't work as hard.

The Gradient Fix

Research and coaching consensus suggest that setting the treadmill at 1–2% incline best simulates running on flat road. This small gradient forces more glute and calf engagement, while also compensating for the lack of wind resistance indoors.

Curved (Woodway) vs Traditional Treadmills

Curved treadmills are non-motorised and rely on your own power to move the belt. This creates a much more natural running action requiring active push-off. They engage the glutes and hamstrings properly and allow for natural push-off and stride mechanics. However, they can feel harder than outdoor running, limiting session duration, and aren't ideal for very long runs or precise interval work.

Traditional motorised treadmills are better for long runs, controlled pacing, and structured workouts. They're gentle on joints but have artificial running mechanics.

The Bottom Line

Don't obsess over treadmill pace — train by time and effort. Don't keep it flat — set the gradient at 1–2%. A treadmill should complement your outdoor training, not replace it.