Spending extra hours at work and with your family is important. But if you want to be productive at the office and energized at home, you also need to spend enough time sleeping.

"We see a lot of people functioning at less than optimum because they are trying to get by on too little sleep," says Dr. Martha Lentz, a research associate professor in the UW School of Nursing. Lentz studies the relationship of circadian rhythms, body temperature and sleep in older women, as well as the relationship between stress and insomnia.

Some typical results of chronic sleep deprivation include an increase in irritability and a deterioration of the ability to make good decisions about complex information.

But the fast-lane lifestyle so in vogue these days can make getting enough sleep a real challenge, Lentz acknowledges.

"People make time for the things that they value, and we have a myth going around that we sleep too much," Lentz says. "High stress jobs naturally boost levels of chemicals that stimulate nervous system activity, so we need some down time between the excitement and challenges of our work and when we go to sleep."

Drinking coffee during the day for a caffeine boost and drinking alcohol in the evening to relax can also have an adverse effect on sleeping. Even though alcohol might make you feel sleepy, it disrupts the quality of sleep, she says. Alcohol can cause "rebound insomnia," in which you fall asleep easily but wake up a short time later and lie awake.

To improve the quality of your sleep, Lentz suggests:

• Cut down on coffee and other stimulants during the day, and skip the alcohol before bed.
• Stick to a regular schedule for going to bed and waking up, even on weekends.
• Get some light exercise in the late afternoon or early evening.
• Spend some quiet time before going to bed.
• Don't do stressful activities (like working on the report your boss has been pestering you about) in the bedroom.

Take heart, short term sleep debt can be repaid by sleeping a little extra for a few days, Lentz says. Chronic sleep deprivation is more difficult to overcome, but a few months of getting some extra sleep should do it.