A practical, science-informed digital guide (about 22,000 words) for high-stress male executives ages 35–55. It teaches quick heart rate variability (HRV) biofeedback routines and simple breathing protocols that fit busy calendars. It includes daypart-specific stacks (morning, midday, evening), travel strategies, boardroom prep and decompression tools, and plug-and-play templates for Apple Watch, Oura, Whoop, and Garmin. The focus is on fast, measurable stress relief to lower cortisol and support healthy testosterone through better sleep and steadier daily rhythm.