Your attention is your most valuable asset, and Amy Landino knows exactly how to protect it. In this video, she introduces the 90-minute sprint --- a deep work protocol designed to maximize cognitive output without burning out. Grounded in research on ultradian rhythms (the body's natural 90-minute energy cycles), this method structures work into intense, uninterrupted blocks followed by deliberate recovery. Amy breaks down exactly how to set up a sprint, how to protect it from interruptions, what to do during the recovery phase, and how to stack multiple sprints for an extraordinarily productive day. This isn't just a technique for knowledge workers --- it applies to creators, entrepreneurs, and anyone doing cognitively demanding work. If you've ever ended a busy day feeling like you got nothing meaningful done, the 90-minute sprint might be the single most impactful change you can make this week.