Exactly what I need to help me get through stressful days

This is a wonderful app. The 5 minutes is all I need. I appreciate how simple it is. The only thing it doesnt have is more information. Why is this exercise healthy? What is it doing to my body? Should I ever lower the target bpm? I wish I could read the research associated with this project. Other than that, its a wonderful addition to my day and Im so happy its free!

ShacAttack about Breathing Zone Free - Relaxing Breathing Exercises