Any process that activates or increases the frequency, rate or extent of slow-twitch skeletal muscle contraction.
Synonyms:
exact_synonym:
positive regulation of slow-twitch skeletal muscle contraction; up regulation of slow-twitch skeletal muscle contraction; upregulation of slow-twitch skeletal muscle contraction
narrow_synonym:
activation of slow-twitch skeletal muscle contraction; stimulation of slow-twitch skeletal muscle contraction