Early birds may be more active, but night owls can catch up

Being an early bird has long been associated with a go-getter attitude. Early birds, or those who tend to wake early and go to bed early, are people who naturally feel sleepy earlier in the evening and naturally wake early in the morning. For an early bird type, a 9 p.m. bedtime may be the norm, and rising at 5 a.m. without an alarm clock feels relatively effortless.

Our internal clock controls more than sleep patterns

Being an early bird — or the opposite, a night owl — is usually not something that is thought of as being highly under our control. Some people seem to be hardwired to sleep early, while others get a second wind and tend to sleep late. This internal clock is called our circadian rhythm, each person's unique internal timekeeper and the body's own master controller of many functions. Most obvious is our sleep patterns; however, our internal clock also plays a role in our hunger and eating patterns, hormone levels, and maybe even our mood.

Does being an early bird or night owl affect our health?

A growing body of research shows that we may want to pay more attention to circadian rhythm, also called our chronotype. Identifying if we're more of an early bird or night owl may help predict our risk of potential health problems.

A recent study from the Scandinavian Journal of Medicine and Science in Sports looked at whether the body clock is related to levels of physical activity. Using a wrist-based device that measures movement, over 5,000 participants' activity levels were collected for two weeks. Researchers also identified whether each person was more of an early bird or night owl, based on a well-studied questionnaire. After considering some factors that may explain differences, such as education or background health conditions, they found that being a night owl was linked to lower physical activity. Night owls, as compared to morning types, had up to 60 to 90 fewer minutes per day of activity.

Why might your body's clock and your activity level be linked?

In short, more research in this area is needed to know for sure. Most studies on this topic look at patterns; there seem to be trends emerging that certain body clock patterns and health conditions run together. What we don't know, though, is whether being a night owl or early bird is the cause. But when trying to understand why, there are a number of potential factors that come into play.

For those with a more of a night owl or an "eveningness" type, it may be more of a challenge to incorporate activity into their day. For many night owls, jobs or other demands on time may mean that a morning alarm is sounding well before their natural wake time. As a result, a night owl type may be starting the day relatively "jet lagged" — feeling out of sync with their body due to being awake when the body would prefer to be asleep. They also may be sleep deprived if they had to get up significantly earlier than desired. These may contribute to less activity on a regular basis.

On days off, catching up on sleep may become a priority given too little sleep during the week. Sleep patterns, such as how much or when people are sleeping, are potentially the key here, but this information wasn't captured in this study. Other health conditions or behaviors that interfere with sleep, such as mood disorders, may be found more often among night owls.

If I'm a night owl, what can I do?

We should emphasize that this study does not tell us that being a night owl is the cause for lower physical activity. (This is true for much research around our body clock, as previously mentioned.) It simply shows an association between being an early bird or night owl and certain conditions. In addition, the factors at play — sleep patterns and activity — are factors we have some control over. Though we may be hardwired to lean toward being a night owl or morning bird, most people fall somewhere in the middle. Sleep patterns and activity are modifiable, and even small changes can have a big impact over days, weeks, months, and years.

Reflecting on your sleep patterns is one way to take advantage of the best times of the day for more activity. Are you someone who feels ready and alert first thing in the morning? That may be the best time to get those steps in. More energy in the evening? Then scheduling that walk for after dinner may be best. Using your body clock to your advantage may help optimize the best time to be active.