Brown Frederick M, Neft Evan E, LaJambe Cynthia M
Department of Psychology, The Pennsylvania State University, University Park, Pennsylvania, USA.
J Strength Cond Res. 2008 Nov;22(6):1894-900. doi: 10.1519/JSC.0b013e318187534c.
During adolescence and early adulthood, most humans are predisposed developmentally, both biologically and socially, toward evening/night activity. The morningness-eveningness (M-E) tendency to be an evening-preferring (E-type) rather than a morning-preferring (M-type) or intermediate/neither (N-type) "chronotype" may affect athletic performance at various times of day. This study evaluated M-E effects on rowing performance of an intact, experienced, university club crew with near-daily early morning (0500-0700 hours) and late afternoon (1630-1800 hours) training schedules. The hypothesis tested was that chronotype would modify circadian effects during morning and afternoon performances. Eight men and eight women (mean age 19.6 +/- 1.5 years) were tested in a randomized, counterbalanced design. A standard qualifying 2000-m ergometer rowing sprint and a nonroutine standing broad jump task were measured during early morning and late afternoon, separated by 3 days of rest. Each subject's chronotype was determined using two standard self-rating M-E scales, resulting in eight E-type (three women/five men), four M-type (two women/two men), and four N-type (three women/one man) subjects. The rowing results show that E-type and N-type subjects did not differ between morning and afternoon rowing performances, whereas M-type subjects rowed significantly faster in the morning. In contrast, the standing broad jump showed no consistent time-of-day or chronotype effect. These findings suggest that basic performance timing in young athletes is determined to some extent by naturally occurring M-E predispositions. Further, modification of time-of-day influences may be possible by routine practice at the same time each day, as was suggested here by the absence of evening superiority in performances. Understanding their personal M-E tendencies could allow young athletes to arrange training schedules at specific times of day to help counteract any natural circadian influences that might work against their performance.
在青春期和成年早期，大多数人在生理和社会发展方面倾向于夜间活动。晨型-夜型（M-E）倾向，即偏好夜晚（E型）而非偏好早晨（M型）或中间型/无明显偏好（N型）的“昼夜节律类型”，可能会在一天中的不同时间影响运动表现。本研究评估了M-E对一个完整、经验丰富的大学俱乐部赛艇队赛艇表现的影响，该队有近乎每日的清晨（05:00 - 07:00）和傍晚（16:30 - 18:00）训练计划。所检验的假设是昼夜节律类型会改变早晨和下午表现期间的昼夜节律效应。八名男性和八名女性（平均年龄19.6±1.5岁）接受了随机、平衡设计的测试。在清晨和傍晚分别进行了一项标准的2000米测力计赛艇冲刺赛和一项非常规的立定跳远任务，中间间隔3天休息。使用两个标准的自评M-E量表确定每个受试者的昼夜节律类型，结果产生了八名E型（三名女性/五名男性）、四名M型（两名女性/两名男性）和四名N型（三名女性/一名男性）受试者。赛艇结果显示，E型和N型受试者在早晨和下午的赛艇表现上没有差异，而M型受试者在早晨划得明显更快。相比之下，立定跳远没有显示出一致的昼夜时间或昼夜节律类型效应。这些发现表明，年轻运动员的基本表现时间在一定程度上由自然存在的M-E倾向决定。此外，如这里表现中没有傍晚优势所表明的，每天在同一时间进行常规训练可能会改变昼夜时间的影响。了解他们个人的M-E倾向可以让年轻运动员在一天中的特定时间安排训练计划，以帮助抵消任何可能不利于他们表现的自然昼夜节律影响。
