  We discuss the use of the optimization procedure based on the Principle of
Minimal Sensitivity to the third-order calculation of {\mbox{${R_{e^+e^-}}$}}.
The effective coupling constant remains finite allowing us to apply the
Poggio-Quinn-Weinberg smearing method down to energies below 1 GeV, where we
find good agreement between theory and experiment. The couplant freezes to a
value of $\alpha_s/\pi = 0.26$ at zero energy which is in remarkable
concordance with values obtained phenomenologically.
