"I'm just not a morning person," could be a statement that you've repeated time and again... during high school when your mom tried to push you out of bed... or when you were late for a college midterm... or even now as you sit groggily reading this story at work.

But take heart because it's not your fault. The blame lies with modern electricity, according to a new study in Current Biology that says spending time in nature on a camping trip can turn a 'night owl' into a 'morning lark' by resetting the human biological clock.

"When people are living in the modern world-living in these constructed environments-we have the opportunity to have a lot of differences among individuals. Some people are morning types and others like to stay up later," said lead author Professor Kenneth Wright, a physiologist at the University of Colorado Boulder.

"What we found is that natural light-dark cycles provide a strong signal that reduces the differences that we see among people-night owls and early birds-dramatically."

Our internal clocks — or circadian rhythms — tell us when to wake up and to go to bed, but also when we will eat our meals throughout the day. These processes are governed by special hormones released on a tight schedule

Wright and his colleagues measured one of these hormones — melatonin — over the course of one week, while they went about their regular routines. Melatonin controls a person's alertness and when its levels rise at night, people become sleepy. Conversely melatonin are supposed to drop when people wake up in the morning, so they can start their days.

The researchers found that this melatonin schedule was offset in this group, so levels of the hormone didn't fall until about two hours after waking up.

Prior research has suggested that the invention of electrical lights, which allow people stay up late into the night, has disrupted the natural circadian clock, so the investigators took the eight people camping for a week by a lake in the beautiful Rocky Mountains.

During this study period, the subjects were not allowed to use flashlights or even smart phones. Their only source of light after sundown was a campfire.

After only a week, the volunteers' sleep schedules shifted two hours in reverse and they began rising at sunset. This was matched by corresponding change with the release of melatonin into the bloodstream.

This study is just one in a sea of research suggesting that modern living has disrupted natural patterns of human sleep. Last week, a Swiss group reported that humans evolved to respond the lunar cycles, explaining why some people have trouble sleeping during a full moon. And the ever controversial and semiannual switch for daylight saving time is thought to cause a variety of negative health effects.

Harvard epidemiologist explains the health risks of daylight saving time.

Althougth a return to the wild isn't feasible for most of us, Wright argues there are things that we can do to tune our biological clocks to a more natural schedule.

"By increasing our exposure to sunlight and reducing our exposure to electrical lighting at night, we can turn our internal clock and sleep times back and likely make it easier to awaken and be alert in the morning," said Wright.

Source: Wright Jr KP, McHill AW, Birks BR, Griffin BR, Rusterholz T, Chinoy ED. Entrainment of the Human Circadian Clock to the Natural Light-Dark Cycle. Current Biology. 2013.