TRX Training Core Strength DVD, Helps Build Crucial Core Strength, Vol. 1 Fitness instruction DVD for TRX suspension training enthusiasts focuses on building core strength in inner abdominal muscles and lower back Innovative new suspension training program designed to deliver total functional training of core musculature Fitness Anywhere Director of Education Fraser Quelch created this two-workout regimen, and also guides the exercises See visible results, improve your posture, feel stronger, and be able to take fitness goals to the next level Includes 30-day satisfaction guarantee