The X3 resistance training program used in Step 4 of the Superhuman Protocol is an effective method to improve muscle strength, tone, and endurance. Resistance training utilizes resistance bands or weights to create tension that forces the muscles to work harder. This increased tension can lead to muscle growth, improved metabolic function, and enhanced overall physical performance. The program allows for targeted muscle group training and can be tailored to the individual's fitness level and goals. Additionally, resistance training has been shown to improve bone density and reduce the risk of injury. When combined with other Superhuman Protocol steps, resistance training becomes a key factor in achieving optimal athletic performance and overall health.