The ornamental design for an exerciseresistancedevice for a seated user, as shown and described.
FIG. 1 is a perspective view taken from below of an exercise resistance device for a seated user;
FIG. 2 is another perspective view taken from above thereof, and FIG. 2 shows the surface of the exercise resistance device for a seated user upon which a user would sit in a typical configuration of the exercise resistance device for a seated user;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a top plan view thereof; and,
FIG. 5 is a right side elevational view thereof, the left side being a mirror image.
The broken lines showing portions of the exercise resistance device for a seated user depicts environment and forms no part of the claim.