Abstract: A wearable robotic device configured to provide exercise for a human user. A primary use of the device is to address muscle and bone density loss for astronauts spending extended periods in microgravity. In one configuration the device applies a compressive force between a users feet and torso. This force acts very generally like gravity—forcing the user to exert a reactive force. The compressive force is precisely controlled using a processor running software so that a virtually endless variety of force applications are possible. For example, the wearable device can be configured to apply a gravity-simulating force throughout the device's range of motion. The robotic device may also be configurable for non-wearable uses. In these cases the robotic device may act as an exercise machine. The programmable nature of the force application allows the device to simulate weight-training devices and other useful exercise devices.