A selectively inclining hiking exercise apparatus supports a user ambulating thereon. The selectively inclining hiking exercise apparatus includes a support base and a treadbase that selectively inclines with respect to the support base. The treadbase includes a motor for driving an endless belt upon which the user ambulates. The treadbase also includes a magnetic braking assembly for regulating the speed of the endless belt to prevent the endless belt from moving at a rate that is faster than the rate at which the treadbase motor is driving the endless belt. The magnetic braking assembly includes a magnet that selectively moves relative to the treadbase flywheel along a threaded lead screw to provide the braking force.