Whether you are new to tri or have taken a long break, Spinervals Competition 21 Aero Base Builder IV will help build and develop your aerobic base. This 70 minute DVD with Coach Troy Jacobson focuses on training your blue aerobic zone, which is ideal for long races by getting your body to adapt to using fats for as the primary fuel. There is an option to turn off the audio so you can jam to your own music if wanted. Compatible with all stationary bikes.
