A resistance mechanism for an exercising device is provided. The resistance mechanism comprises a housing configured to engage the exercise device. The housing is configured to translate a resistance from a resistance generator to the exercise device. The resistance mechanism also comprises a resistance adjustment mechanism configured to adjust a level of resistance provided by the resistance mechanism. Adjustment in a first direction increases a provided resistance, and adjustment in a second direction decreases the provided resistance. The resistance generator comprises a flywheel coupled to an indexing wedge. The resistance mechanism is configured to, when the adjustment mechanism adjusts in the first direction, push against the indexing wedge in a linear direction towards and against a brake arm, causing the brake arm to engage the flywheel, thereby increasing the level of resistance provided by the resistance mechanism to the outdoor exercise device.