Allie Costin instructs the following:
GRIT™ Strength is a 30-minute high-intensity interval training (HIIT) workout, designed to improve strength and build lean muscle. This workout uses barbell, weight plate and body weight exercises to blast all major muscle groups.
GRIT™ Plyo is a 30-minute high-intensity interval training (HIIT) plyometric-based workout, designed to make you perform like an athlete. This workout uses a bench and combines explosive jumping exercises with agility training to increase explosiveness and to build a lean and athletic body.