Soviet POWs ill-equipped to handle Finnish winter during Winter War

The transcript describes the Finnish resistance against the Russian invasion during a harsh winter. Initially, the Finnish forces successfully bewildered the Russian troops. As the Mannerheim Line held strong, Russia reorganized its military under General Tymoshenko, launching a major offensive with 300,000 troops. Despite being outnumbered, the Finnish army employed scorched earth tactics, burning buildings to deny the Russians shelter from the severe cold, which affected both sides.

What strategy did the Finnish army employ to hinder the advancing Russians?

What extreme weather conditions did both the Finns and Soviets face?