After filling up the V - Trigger gauge, you can unleash every character's special attack by pressing the heavy punch and heavy kick buttons. (softpedia.com)
What this means is that after a hard knockdown (being hit by a crouching heavy kick or throw), you can decide to get up at the normal rate or delay it, thus making tricky setups by your opponent more difficult and inconsistent to pull off. (darkstation.com)
I.e. the shotos... Jump in heavy kick, crouching medium kick, projectile move of choice. (metacritic.com)