When it comes to engaging in activities such as sex, sleep or exercise, it seems that the ‘when’ is just as important as ‘how’.

According to clinical psychologist and sleep-disorder specialist Michael Breus, timing could be the key to success and pleasure in your daily pursuits. His new book, The Power of When, breaks down 75 different activities, from drinking coffee to going for a run, and assesses the optimum time for you to do them based on your biological clock.

Breus has identified four chronotypes, according to personality and sleep requirements: the dolphin, lion, wolf and bear.

The ‘dolphin’ is an intelligent and neurotic light-sleeper; the ‘lion’ is an ambitious, optimistic morning person; the ‘wolf’ is night-oriented, creative and extroverted; and the ‘bear’ is outgoing and loves fun and sunlight.

“Everyone’s internal rhythm is different,” he says. “There are certain times when our body is burning calories or producing more oestrogen, so it’s all about using that knowledge.”

So, when is the best time for you to:

Go to sleep?
Dolphin: 11.30pm
Lion: 10pm
Wolf: Midnight
Bear: 11pm

Wake up?
Dolphin: 6.30am
Lion: 5.30am to 6am
Wolf: 7.30am
Bear: 7am

Exercise?
Dolphin: 7.30am
Lion: 5.30pm
Wolf: 6pm
Bear: 7.30am or 12pm

Have sex?
Dolphin: 8pm
Lion: Between 6am and 7am
Wolf: 10am or 10.30pm
Bear: 7am or 9pm

Read more at New York Post.

Do you think there’s something to the idea of ‘when’? Would you try adjusting your schedule to suit your chronotype?