Complain about poor sleep when blamed on failure of concentrating on work?

As a matter of fact, large percent of such cases could be eliminated if you just pay more attention to some habits & your way of living.

Control the Quantity of Caffeine
Taking superfluous caffeine a day could be the cause, if you have difficulties in sleep. Try to cut your caffeine consumption to just one or two glasses per day. Don’t drink any caffeine beverages after lunch. There are plenty of beverages without caffeine.

Avoid Alcohol
Although alcohol initially can make you drowsy, it suppresses the normal stage of sleep by restoreing the sense of well-being later. Avoid drinking alcohol, especially when it is draw near bedtime.

Take Exercises Regularly
Many of us don’t move about our bodies unless we are asked to do so. We’re often too mentally fatigued to get off the couch when we get home from work. Our brains may be exhausted, but our bodies may not be the same. Generally, one needs taking exercises for at least 30 minutes a day. But don’t do that when you are going to sleep for it will keep you awake, leave a 2-3 hours window between exercise and time to go to sleep.

Go to bed on Time & Skip the Late Show
Go to bed & get up at the same time everyday. Yes, even on weekends and holidays. All the sleep researches agree with that principle. Begin with the time in the evening when you go to bed, you need at least 8 hours’ sleep everyday. And do the match in the morning. It might be a pity to miss late show like soaps in late evening, but all are for your health, if you stay up very late everyday, and then what you will miss is much than just soaps.