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According to clinical psychologist and author Michael Breus, there are four types of people in this world: dolphins, lions, bears and wolves.
Which category, or animal, you fall into is determined by your "internal rhythm" - based on sleep patterns and personality.
In an interview with the New York Post, the author explained:
There are certain times when our body is burning calories or producing more oestrogen, so it’s all about using that knowledge.
Breus, who has written about his findings in The Power of When, says these are the times different people should be...
Dolphin: 11:30pm - 6.30am
Lion: 10pm - 5.30/6am
Wolf: midnight - 7am
Bear: 11pm - 7.30am
Bear: 7:30am or 12pm
Dolphin: 3pm - 9pm
Lion: 8am - 12pm
Bear: 10am - 2pm
Wolf: 5pm - midnight
Lion: 6am to 7am
Bear: 7am or 9pm
Wolf: 10am or 10:30am
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