Effects of Imagery and Breathing Exercises on Swimmers' Performance, Mental Toughness, and Heart-Mind Coherence

Participants performed daily imagery and breathing exercises before bedtime for 10 weeks. The protocol involved a 4-second inhale through the nose and a 4-second exhale through the mouth while visualizing a 200-meter freestyle swim with detailed attention to technique and performance. A 6-day training period was provided to teach the techniques, and participants received daily reminders and feedback via a WhatsApp group.