A manual non-motorized exercise treadmill with the ability to provide adjustable resistance to perform strength training resistance movements and simulate the movements of an exercise drive sled in a stationary location is described. A treadmill deck of the treadmill is supported by friction-reduction rollers, a front treadmill roller and a rear treadmill roller. The treadmill is operated by the user pushing and/or pulling with the feet of the user via a belt or harness attached to adjustable stationary hand bars. Variable resistance allows for increased or decreased difficulty in achieving the exercise according to the preference and ability of the user. The resistance is configured to be applied to the rollers and/or belt, making it more difficult for the user to manually move the treadmill belt. The treadmill belt is configured to oscillate for both concentric and eccentric exercises not provided by conventional treadmills.