Systems and methods for determining the effectiveness of breath training regimens are disclosed. The systems include a sensor assembly configured to detect data indicative of at least one physiological parameter of a user during breath training sessions while the user is awake and while the user is asleep. The system also includes an electronic computing unit with a processor configured to analyze the data indicative of the at least one physiological parameter of the user detected by the sensor assembly, and determine effectiveness of the breath training sessions on the user by determining trends of the at least one physiological parameter of the user from the analyzed data, and determining changes in the at least one physiological parameter of the user while the user is asleep occurring during a period of time from the determined trends.