7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
1 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
2:30 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
4 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
5:30 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
7 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
8:30 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
10 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
11:30 p.m.
What I’m doing:
Mental alertness: 1 2 3 4 5 6 7 8 9 10 NA
Physical energy: 1 2 3 4 5 6 7 8 9 10 NA
WHAT TO DO IF YOU DON’T HAVE CONTROL OVER YOUR DAILY SCHEDULE
The harsh reality of work—whatever we do, whatever our title—is that many of us don’t fully control our time. So what can you do when the rhythms of your daily pattern don’t coincide with the demands of your own daily schedule? I can’t offer a magic remedy, but I can suggest two strategies to minimize the harm.
1. Be aware.
Simply knowing that you’re operating at a suboptimal time can be helpful because you can correct for your chronotype in small but powerful ways.
Suppose you’re an owl forced to attend an early-morning meeting. Take some preventive measures. The night before, make a list of everything you’ll need for the gathering. Before you sit down at the conference table, go for a quick walk outside—ten minutes or so. Or do a small good deed for a colleague—buy him a coffee or help him carry some boxes—which will boost your mood. During the meeting, be extra vigilant. For instance, if someone asks you a question, repeat it before you answer to make sure you’ve gotten it right.
2. Work the margins
Even if you can’t control the big things, you might still be able to shape the little things. If you’re a lark or a third bird and happen to have a free hour in the morning, don’t fritter it away on e-mail. Spend those sixty minutes doing your most important work. Try managing up, too. Gently tell your boss when you work best, but put it in terms of what’s good for the organization. (“I get the most done on the big project you assigned me during the mornings—so maybe I should attend fewer meetings before noon.”) And start small. You’ve heard of “casual Fridays.” Maybe suggest “chronotype Fridays,” one Friday a month when everyone can work at their preferred schedule. Or perhaps declare your own chronotype Friday. Finally, take advantage of those times when you do have control over your schedule. On weekends or holidays, craft a schedule that maximizes the synchrony effect. For example, if you’re a lark and you’re writing a novel, get up early, write until 1 p.m., and save your grocery shopping and dry-cleaning pickup for the afternoon.
WHEN TO EXERCISE: THE ULTIMATE GUIDE
I’ve focused mostly on the emotional and cognitive aspects of our lives. But what about the physical? In particular, what’s the best time to exercise? The answer depends in part on your goals. Here’s a simple guide, based on exercise research, to help you decide.
Exercise in the morning to:
• Lose weight: When we first wake up, having not eaten for at least eight hours, our blood sugar is low. Since we need blood sugar to fuel a run, morning exercise will use the fat stored in our tissues to supply the energy we need. (When we exercise after eating, we use the energy from the food we’ve just consumed.) In many cases, morning exercise may burn 20 percent more fat than later, post-food workouts.1
• Boost mood: Cardio workouts—swimming, running, even walking the dog—can elevate mood. When we exercise in the morning, we enjoy these effects all day. If you wait to exercise until the evening, you’ll end up sleeping through some of the good feelings.
• Keep to your routine: Some studies suggest that we’re more likely to adhere to our workout routine when we do it in the morning.2 So if you find yourself struggling to stick with a plan, morning exercise, especially if you enlist a regular partner, can help you form a habit.
• Build strength: Our physiology changes throughout the day. One example: the hormone testosterone, whose levels peak in the morning. Testosterone helps build muscle, so if you’re doing weight training, schedule your workout for those early-morning hours.
Exercise in the late afternoon or evening to:
• Avoid injury: When our muscles are warm, they’re more elastic and less prone to injury. That’s why they call what we do at the beginning of our workout a “warm-up.” Our body temperature is low when we first wake up, rises steadily throughout the day, and peaks in the late afternoon and early evening. That means that in later-in-the-day workouts our muscles are warmer and injuries are less common.3
• Perform your best: Working out in the afternoons not only means that you’re less likely to get injured, it also helps you sprint faster and lift more. Lung function is highest this time of the day, so your circulation system can distribute more oxygen and nutrients.4 This is also the time of day when strength peaks, reaction time quickens, hand-eye coordination sharpens, and heart rate and blood pressure drop. These factors make it a great time to put on your best athletic performance. In fact, a disproportionate number of Olympic records, especially in running and swimming, are set in the late afternoon and early evening.5
• Enjoy the workout a bit more: People typically perceive that they’re exerting themselves a little less in the afternoon even if they’re doing exactly the same exercise routine as in the morning.6 This suggests that afternoons may make workouts a little less taxing on the mind and soul.
