Running in bad shoes gives pain and reduces speed in real life. Different kinds of clothing for different weather, frostbite is painful and reduces functionality. Dropping from height can cause limping and pain, not necessarily a broken limb. There are many ways to improve the player-model concerning degradation of functionality. Pain is not binary, it can be anything from annoying to paralyzing. It should be a player dilemma: do I take the goretex jacket or do i choose another gun?