Most yogis feel freer when they look inward and choose poses that are healing and nurturing—even if that means doing something different than what they originally thought they'd do. This insight is spelled out in the eight limbs of classical ashtanga yoga, which ultimately lead to samadhi, or freedom.
The first limb is yama, a group of five qualities that can be summed up as "self-restraint" or "control." Among other things, the yamas teach us about ahimsa (nonviolence) and satya (truthfulness). So when you apply nonviolence and truthfulness to your practice—avoiding poses that don't feel right or that might cause injury—you eventually reach a place of freedom.