We study the dielectric relaxation of polycarbonate (PC) at room temperature under imposed strain rate (gamma) over dot, above the yield stress, and up to 13% strain. We find that the dielectric response of stretched PC behaves as if it was heated up at a temperature just below its glass transition temperature, T-g approximate to 423 K for PC. Indeed, in the frequency range of our experiment (10(-2) and 10(3) Hz), the dielectric response of the stretched PC at room temperature superimposes to the dielectric response of PC at a temperature T-a((gamma) over dot) < T-g, which is a function of strain rate. Specifically we observe that at T-a the dominant relaxation time tau(alpha)(T-a) of PC at rest is related to (gamma) over dot in such a way that tau(alpha)(T-a) similar to 1/(gamma) over dot, at and beyond the yield point. In our experiment, 10(-5) s(-1) < (gamma) over dot < 10(-3) s(-1) the temperature shifts T-g - T-a are of a few kelvin. The mechanical rejuvenation modifies the dielectric response at frequencies smaller than 10 Hz, whereas for higher frequencies the spectrum is only slightly modified.