Exercise machine brake system

An exercise machine, comprising:

• a shaft configured to rotate about an axis;
• a spool configured to receive a strap and, in response to movement of the strap, rotate about the axis and drive rotation of the shaft about the axis;
• a flywheel configured to rotate about the axis;
• two or more conductive coils arranged to generate magnetic fields that induce eddy currents in the flywheel, the two or more conductive coils arranged radially outside the flywheel;
• a clutch configured to engage and disengage transmission of torque between the spool and the flywheel;
• and
• a spring arranged around the axis, the spring configured to exert a return torque on the spool about the axis in response to rotation of the shaft, the return torque causing the spool to rotate about the axis.