FIG. 1 is a front perspective view of a leg exercise machine showing my new design;

FIG. 2 is a left side elevational view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a right side elevational view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a front elevational view thereof; and

FIG. 7 is a rear elevational view thereof.

The broken line showing of a belted human figure in FIG. 1 is for illustrative purposes only and forms no part of the claimed design.