The TRX System, also known as Total Resistance exercises, refers to a specialized form of suspension training that utilizes equipment developed by former U.S. Navy SEAL Randy Hetrick. TRX is a form of suspension training that uses body weight exercises to develop strength, balance, flexibility and core stability simultaneously. It requires the use of the TRX Suspension Trainer, a performance training tool that leverages gravity and the user’s body weight to complete the exercises. TRX's designers claim that it draws on research from the military, pro sports, and academic institutions along with experience gathered from the TRX team, who work "with thousands of athletes, coaches, trainers, first responders, subject matter experts, professors, and service members in all branches."