ERG mode on a smart trainer: automatic power control explained

In ERG mode, a workout sets a target power and the smart trainer adjusts resistance automatically. Pedal faster and resistance decreases. Let cadence fall and resistance increases. The prescribed wattage remains the target.

When is ERG mode useful?

ERG works best for structured sessions with clear power steps. Sweet spot blocks, threshold intervals and recovery sections can be completed without constant shifting. KOMRIDER sends each target to a compatible smart trainer through Bluetooth FTMS.

You do not need to chase the power number manually. This leaves more attention for cadence, position and breathing.

Choose a sensible gear

Gear choice still affects how the trainer feels. A middle gear usually gives stable control. Very large gears create more flywheel speed, while small gears may react more directly.

Select a gear that lets you reach your preferred cadence comfortably before the interval begins. Repeated shifting during a steady ERG step is rarely necessary.

What is the ERG spiral?

When cadence drops sharply, the trainer adds resistance to maintain target power. Pedalling becomes harder, cadence falls further and the rider may stall. This is often called the ERG spiral.

Keep the cranks moving before a power increase and raise cadence slightly before the new step starts. If you stop completely, pause safely and restart instead of forcing the pedals against very high resistance.

ERG mode or route simulation?

In ERG mode, the workout controls the load. In route simulation, the elevation profile controls resistance. KOMRIDER supports both. Choose ERG for precise intervals and route simulation when preparing for a real GPX course.