Assault Fitness AirRunner

A motorless curved treadmill that forces you to generate every step with your own power. The AirRunner burns 30% more calories than a motorized treadmill at the same perceived effort because there's no belt doing work for you. CrossFit Games athletes train on them, tactical fitness programs swear by them, and the slatted belt lasts significantly longer than traditional treadmill belts. Zero electricity, zero maintenance, zero coasting.