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December 12, 2016

The Power of When

screen-shot-2016-12-09-at-12-46-26-pmThe Power of When

By: Michael Breus, PhD


Written by Michael Breus, PhD, a clinical psychologist and Fellow of the American Academy of Sleep Medicine, The Power of When offers scientific research about the significance of when we do certain things for both our health and productivity.  Although most of us know the what of health and productivity, these insights about the when can make a huge difference in our lives.  Breus’s argument is that our circadian rhythms fall into four categories, rather than the traditional morning lark/night owl dichotomy, and that when we know our “chronotype” and the rhythms of our various sleep-related hormones, we can make better decisions about when to do almost any type of activity.  He then associates those chronotypes with four mammals–Dolphins, Lions, Bears, and Wolves, based on some of their sleep/wake characteristics.  An assessment is provided at the beginning of the book to help you nail down where you fall on the spectrum.

Personally, I found this book incredibly helpful.  I took lots of notes and was easily able to start applying his advice to my daily routine.  Time will tell if it “works” for me, but I found that I was already naturally applying some of his advice according to my Bear chronotype (the majority of the population).  After chapters covering a “day in the life”–both typical and ideal–of each chronotype, the following chapters are short and packed with valuable information.  Each of these chapters presents various “rhythms” scientists have discovered that influence the best time to do a certain thing, such as exercise, eat meals, ask for a raise, or do something creative.  Breus then applies these to the chronotypes and suggests the best time to do the activity for each type.

My main criticism of the book is the personality traits he attributes to the types, as I think it tended to overgeneralize and not account for the many other factors that make up our personalities.  However, his theories and advice should benefit anyone, whether you suffer from lack of sleep, food cravings at night, or a midday slump.  Insomniacs especially (often categorized as Dolphins) would benefit most from trying out the recommendations in this book.

Review By:  Alison Frolik