这里是美国之音慢速英语健康报告。
Parents know a nightly bedtime is not always easy to enforce. But researchers say bedtime rules may improve a child's development.
家长们知道每晚按时就寝不容易执行。但研究人员表示，规律的就寝时间有利于儿童成长发育。
A new study found better results in four-year-olds who go to bed around the same time every night and sleep at least eleven hours. Getting less than that was linked to lower abilities in language, reading and early math skills.
一项新的研究发现，每晚按时就寝且睡眠时间至少11小时的4岁儿童具有良好的结果。达不到这些睡眠要求的儿童则与语言、阅读、初等数学能力较低联系起来。
Researchers at SRI International in California did the study. It involved about eight thousand preschool children whose parents took part in government research on early childhood.
斯坦福国际研究院（SRI International）的研究人员进行了这项研究。涉及到大约8千名其家长参加政府幼儿教育研究的学前儿童。
The parents answered questions by telephone at nine months and again at four years. The amount of sleep was based on their reporting of a child's usual bedtime and wake time. These were not independently confirmed.
家长们在孩子9个月和4岁的时候通过电话接受调查。睡眠时间的长短来自于他们对孩子日常就寝和起床时间的报告，这些数据没有得到独立证实。
SRI policy researcher Erika Gaylor says doctors can easily try to get parents to set regular bedtimes. And at bedtime she urges parents to follow routines like reading books or telling stories to their children.
斯坦福国际研究院的政策研究员Erika Gaylor表示，医生可以简单地尝试让父母给孩子们设置规律的作息时间，同时她呼吁父母在孩子们睡前进行一些些像阅读、讲故事这种睡前准备工作。
For most measures of development, the study found that an earlier bedtime was also a predictor of higher scores.
研究发现，对于儿童成长发育的各类衡量标准来说，早睡也是获得更高分的前提。
Last August, a study in the journal Sleep Medicine said children who go to bed after nine o'clock took longer to fall asleep and slept less. The study found that children also got less sleep if they did not have bedtime routines.
发表在去年8月的睡眠医学杂志上的一份研究称，9点以后上床的孩子入睡时间更长，睡眠更少。研究同时发现，没做睡前准备的孩子睡眠也更少。
The new findings were presented this week in San Antonio, Texas, at a meeting of the Associated Professional Sleep Societies.
这项新发现本周在德克萨斯州圣安东尼奥市召开的联合专业睡眠协会(Associated Professional Sleep Societies)会议上发表。
A separate study found that more sleep may even make a person run faster. The study was small -- seven players on the Stanford University football team. For the study, they aimed for at least ten hours of sleep each night during the season.
另一项研究发现，充足睡眠甚至能使人跑得更快。这项研究是在小范围内进行--研究对象是斯坦福大学橄榄球队的7名队员。为了进行这项研究，他们准备在本赛季每晚至少睡足10个小时。
After seven to eight weeks of more sleep, the players ran faster in short training races. They also felt less sleepy during the day.
经过7到8周的充分睡眠，这些球员在短期训练比赛中跑得更快，他们还感觉在白天更有精神。
Stanford sleep researcher Cheri Mah says sleep should be part of an athlete's training program. This is some of her advice: Before competition, extend your nightly sleep for several weeks to reduce a sleep debt. Adults should try to get seven to eight hours of sleep a night. Teenagers and young adults should aim for nine hours or more. Go to bed and wake up at the same times every day. And take brief naps during the day to get extra sleep.
斯坦福睡眠研究员Cheri Mah表示，睡眠应该是运动员训练计划的一部分。以下是她的一些建议：比赛前几周，延长睡眠时间以减少睡眠债。成年人每晚尽量睡7-8小时，青少年和儿童则应睡9小时以上。每天按时就寝、起床。白天小睡片刻以获得额外睡眠时间。