Are you a dolphin, a bear, a wolf or a lion?

The best time to wake, eat, sleep, exercise or go shopping

You've probably already seen a lot of tricks and tips about the "what" and "how" of success (how to lose weight; what to say to your boss to get a pay increase, etc). "What" and "how" are excellent and necessary questions - but there is another crucial question that must be addressed in order to make fast, dramatic, lasting improvements in the quality of your life across the board.

"When" is the ultimate life hack. It's the foundation of success, the key that unlocks a faster, smarter, better and stronger you. Knowing "when" enables you to perform "what" and "how" to your maximum potential. Having worked with patients who suffer from sleep disorders for over 15 years, I've learnt that you only need to make micro-adjustments to start seeing benefits. Let's say you change the time of your first cup of coffee in the morning so that it better fits your body's needs. The action will nudge the rhythm of your entire day back in sync with the rhythm of your biology. One small change helps everything to feel easier and flow naturally.

Good timing isn't something you choose, guess, or have to figure out. It's already happening inside you, in your DNA, from the minute you wake up to the minute you fall asleep. An inner clock embedded inside your brain has been ticking away, keeping perfect time, since you were a baby. This precisely engineered timekeeper is called your circadian pacemaker, or biological clock. Specifically, it's a group of nerves called the suprachiasmatic nucleus (SCN), in the hypothalamus, right above the pituitary gland.

In the morning, sunlight comes into your eyeballs, travels along the optic nerve, and activates the SCN to begin each day's rhythm. The SCN is the master clock that controls dozens of other clocks throughout your body. Over the course of the day, your core temperature, blood pressure, cognition, hormonal flow, energy, metabolism, creativity, sociability, and athleticism, among many other functions, are governed by the commands of your inner clocks.

For 50,000 years, these clocks ruled human life. Our ancestors ate, hunted, gathered, socialised, rose, rested, procreated, and healed on perfect bio-time. We rose with the sun, spent most of the day outdoors, and slept in total darkness. And then we created civilisation and societies and made incredible advances that, ironically and effectively, turned our finely tuned and evolved inner clocks against us. Working hours and dinnertime shifted later and later. We started to spend more time indoors exposed to artificial light and less time outdoors under the sun. Today, thanks to computer technology, we live in a 24/7 smartphone culture of perpetual dusk where we work, play and eat around the clock.

It's taken only 125 years to undo 50,000 years of perfect bio-timekeeping. No wonder our physiology hasn't kept up. Our "when" is way off - which is why scientists are now connecting the so-called diseases of civilisation (mood disorders, heart disease, diabetes, cancer and obesity) with a phenomenon they term "chrono-misalignment". Symptoms include insomnia and sleep deprivation, which lead to depression, anxiety, and accidents, to say nothing of what feeling overwhelmed and exhausted does to relationships, careers, and health.

For example, morning types tend to be more health-conscious. Evening types tend to be impulsive. Neither type tends to be easy-going.

There's no "one-size-fits-all" fix to chrono-misalignment, because not every person's biological clock keeps the same time. According to conventional wisdom, there are three chronotypes: larks rise early, owls rise late, and hummingbirds are somewhere between the two. I've always been bothered by these categories. Yes, we tend to naturally wake up at different times, but we also have different "sleep drives" - the amount of sleep we need every night.

And then there's personality, which is incredibly important for figuring out chronotype. For example, morning types tend to be more health-conscious. Evening types tend to be impulsive. Neither type tends to be easy-going. In a comprehensive evaluation of chronotype, personality is simply too big and relevant to ignore.

I believe there are four distinct chronotypes and they deserve new names, because humans are mammals, not birds. To start realigning your body to its natural rhythm, try to work out which one most accurately describes you (or your parents, as chronotype is genetic, passed through the PER3 gene). From there, you can discover the best times of day to do quotidian or uncommon things, from when to go shopping to falling in love.

What's your chronotype?

1 DOLPHIN

Personality: cautious, introverted, neurotic, intelligent

Key behaviours: avoids risky situations, strives for perfection, fixates on details

Sleep/alertness pattern: wakes up feeling unrefreshed and remains tired until late in the evening, when they hit their stride. They're most alert late at night and most productive in spurts throughout the day

Like real dolphins, who sleep with only half of their brain at a time so the other half can watch out for predators, human dolphins are light sleepers with a low sleep drive. They struggle with waking up multiple times and are susceptible to anxiety-related insomnia. As they lie awake at night, they ruminate about mistakes they've made and things they've said.

Dolphins are often better at working alone than in a team, and confrontation-averse. They don't really care about fitness and don't need to exercise in order to lose weight, since their body mass index (BMI) tends to be low to average.

2 LION

Personality: conscientious, stable, practical, optimistic

Key behaviours: overachieves, prioritises health and fitness, seeks positive interactions

Sleep/alertness pattern: wakes up early, feels tired in the late afternoon, and falls asleep easily. Most alert at noon and most productive in the morning

Lions in nature rise before dawn to hunt. The human equivalent also rises before the sun comes up, is ravenous upon waking, and, after a hearty breakfast, is ready to conquer the goals he or she has set for that day.

They burst with purposeful energy, facing challenges head-on, with clear objectives and strategic plans for success. Most CEOs and entrepreneurs are lions. They also value exercise, because it gives them a way to set and achieve goals.

3 BEAR

Personality: cautious, extrovert, friendly and open-minded

Key behaviours: avoids conflict, aspires to be healthy, prioritises happiness, takes comfort in the familiar

Sleep/alertness pattern: wakes up in a daze after hitting the snooze button, feels tired by mid-to-late evening, and sleeps deeply but not as long as they'd like. Most alert from mid-morning to early afternoon and most productive just before noon

When bears in nature are not hibernating, they are diurnal: active in the day and restful at night. Their human counterparts would prefer to sleep for at least eight hours per night, if not longer. It takes them a couple of hours to feel fully awake in the morning, during which time they feel hungry. In fact, bears are hungry all the time. If food is available, they'll probably eat it - even if it isn't meal or snack time.

They are affable and undramatic, unlikely to scheme to get a colleague's job or to blame others for their mistakes. A good person to have at a party.

4 WOLF

Personality: impulsive, pessimistic, creative, moody

Key behaviours: takes risks, prioritises pleasure, seeks novelty, reacts with emotional intensity

Sleep/alertness pattern: finds waking up before midday tough, and doesn't feel tired until midnight or later. Most alert at 7pm and most productive in the late morning and late evening.

In nature, wolves come alive when the sun goes down and hunt in a pack. A human wolf is similarly night-orientated. They aren't hungry when they wake up, but they become ravenous at night. Their BMI is average to high. Due to their eating schedules and poor choices, they're more likely to have obesity-related diseases.

Wolves are creative, unpredictable and angered by the perception that they are "lazy". The stress of being out of sync means they are susceptible to mood disorders like depression and anxiety.

When to make a big decision

We make decisions every day. Ideally, we'd make careful, rational calls about the many choices in our lives, especially when they have to do with our performance at work. If you use bio-time to choose wisely at work, you will benefit for the rest of your life.

Decisions are made rationally or emotionally, based on how the choice is framed. The "framing effect", a concept in psychology, means that you're likely to make a choice depending on how it's presented to you.

Take this example, known as "the Asian disease question": A deadly Asian disease might kill 600 people. You have two choices for saving some of them. Choice one guarantees that 200 will live. Choice two offers no guarantees, with a slight chance everyone might live, and a higher chance that 400 will die.

The framing effect at work here is in the language. Even though in both outcomes, 200 people are likely to survive, choice one has a positive frame (risk free, 200 will live!), and choice two has a negative frame (high risk, 400 might die!).

Researchers at Appalachian State University asked this question to subjects at multiple times over the course of a day and found that there was a pattern to their responses. When the subjects were "on-peak", they put aside the emotional reactivity and chose the logical, risk-free first option, that 200 would live. But when they were off-peak, they chose the emotional high-risk option, that it's possible everyone might live but that 400 would probably die.

I think we can all agree that it makes sense to use logical cognitive powers to choose rather than making snap emotional decisions. So, the next time you are faced with a quandary, consider waiting for your on-peak times to make the call:

For Dolphins, that means 4pm to 11pm. For Lions it's 6am to 11am. For Bears, 3pm to 11pm while Wolves are on-peak from 5pm to midnight.

When to go shopping

The best time to shop is when you leave your wallet at home. Trust me on this. Every cue in a retail environment - in-store and online - is devised to get you to take out your credit card right now. Outlets spend millions on research to figure out how to appeal to consumers' emotional instability and get them to throw rationality out the window.

Bears and Wolves are more susceptible to impulse purchases than cautious Lions and Dolphins. But in the right circumstances, anyone is vulnerable to making an on-the-spot buy that they'll later regret.

This is especially true of nonmenopausal women during the luteal phase of their cycle (that is, between ovulation and menstruation). According to a survey of 443 women from 18 to 50, those in the luteal phase had less control over their spending and impulse purchasing than those in the follicular and ovulation phases.

Women and men alike: when you are in a state of arousal - not sexual; excited, full of joy - you are likely to make an impulse purchase. For this reason, store environments are visually exciting (bright lights, colours, smells, music). You become distracted, forget what you intended to buy in the first place, and are tempted by stuff that wasn't on your list.

To avoid the impulse, shop when you are least likely to become aroused by an exciting in-store environment. For Wolves, Dolphins and later-rising Bears, this is during the middle of the day. Lions and earlier-rising Bears will have greater wallet control in the morning, but are susceptible in the evening.

One last thing to watch out for to keep your wallet intact: your hunger rhythm. As we all know, you should never go food shopping when you're hungry, or you'll wind up clearing the shelves. Researchers from the University of Minnesota proved that being hungry causes shoppers to spend more on non-food items, too. The team polled 81 shoppers on their hunger level as they exited a department store, and then checked their receipts. The hungry shoppers purchased a greater number of non-food objects and spent nearly twice as much money as those who weren't hungry, regardless of their mood or how long they'd been shopping.

So, try to shop after meals, when you feel full of energy and are not easily distracted. For Dolphins, that's 1pm; Lions should shop at noon; Bears at 2pm and Wolves at 3pm.

When to talk to your kids

When should you talk to your kids? As a psychologist, my simplest answer is: "Whenever they choose to talk to you."

It's only too common to ask a child about his day and get "nothing" and "whatever" in return. But then, when you least expect it, they reveal a fascinating insight into their inner and social lives. Nine times out of 10, those golden moments happen when you're busy doing something else. Children have uncanny timing for seeking out attention when you are least available to give it.

The next time you initiate a little talk with them, check your bio-timing. If you want them to listen, getting the "when" right is just as important as what you have to say. Adult populations are divided by the four chronotypes, but children are far more likely to fall into one or another category depending on their age. They start out as baby Wolves, sleeping during the day and active overnight. Toddlers are Lions, waking predawn and then falling asleep early. By primary school, they've become Bears, following the solar schedule; then, at secondary school, as adolescence kicks in, they turn into Wolves - zombies in the morning and energy surging at night.

Try putting this knowledge into practice. When your child is between the ages of one and six, initiate important conversations immediately after lunch and dinner. Lions experience a drop in blood sugar known as the postprandial dip after eating. For about 30 minutes, they slow down but don't shut down, giving you the perfect window for conversation. From age seven to 12, talks are best held in the 3pm to 5pm window, during their predictable late-afternoon mood boost. For teenagers, wait until around 10pm, when they'll be positively talkative. If you can catch them within an hour of bedtime, they'll surprise you with how much they're willing to reveal.