ENTHUSIASTS liken sleeping under a weighted blanket to being cocoon(把……包裹起来；茧)ed, gently hugged or soothe(抚慰，使平静)d by a light massage. Heavy quilts and sofa throws filled with glass beads or other dense materials have grown popular despite prices that can reach several hundred dollars. Weighted blankets have a curious pedigree: they were inspired in part by padded “squeeze chutes” that restrain and often calm cattle during handling.(重力毯的来历颇为奇特：它的灵感部分来自一种内衬软垫的“挤压通道”，这种装置在处置牛只时将其固定，往往能让牛平静下来。) Might people derive similar measurable benefits from pressure?
爱好者把盖着重力毯睡觉比作被茧包裹、被轻轻拥抱，或被轻柔按摩抚慰。填充玻璃珠或其他高密度材料的厚重被子和沙发毯尽管价格可高达数百美元，却越来越受欢迎。重力毯的来历颇为奇特：它的灵感部分来自一种内衬软垫的“挤压通道”，这种装置在处置牛只时将其固定，往往能让牛平静下来。那么，人是否也能从压力中获得类似的可测量益处呢？
In 2023 the results of a small so-called crossover trial(交叉试验) (in which participants receive the treatment as well as(以及，和) the control) from a sleep laboratory in Sweden were published. Twenty-six healthy young adults had spent a night under a normal blanket and another beneath one weighing about 12% of their respective body weights.(26名健康的年轻成年人分别在普通毯子和一条约相当于各自体重12%的重毯下各睡了一晚。) Each night, for an hour before lights-out, saliva samples were taken. Under the weighted blanket, the rise in salivary levels of melatonin(褪黑素), a hormone that promotes sleep, was on average 32% greater.
2023年，瑞典一家睡眠实验室公布了一项小型“交叉试验”（即受试者既接受治疗也接受对照）的结果。26名健康的年轻成年人分别在普通毯子和一条约相当于各自体重12%的重毯下各睡了一晚。每晚熄灯前一小时，研究人员采集了唾液样本。盖重力毯时，唾液中褪黑素（一种促进睡眠的激素）水平的上升幅度平均高出32%。
That sounds promising. These participants, though, did not sleep for longer when under the heavier blanket. And a single night’s trial says little about sustained(持续的，长期的) use. A larger trial, published in BMC Psychiatry in 2024, therefore followed 95 Chinese adults with diagnosed insomnia(失眠) for a month. Each was randomly assigned a blanket that weighed either 5.5kg or 3.5kg. A device tallied their awakenings during the first week. Those using the heavier blanket woke less often—but only slightly less. At the end of the trial, both groups scored better on a questionnaire measuring insomnia severity, but by statistically indistinguishable amounts.(试验结束时，两组在衡量失眠严重程度的问卷上得分都有改善，但改善幅度在统计上无法区分。) On other questionnaires covering sleep quality and related problems, though, the two groups diverged(出现分歧，分化). Participants using the heavier blanket reported roughly twice the improvement in overall sleep quality, as well as greater reductions in fatigue, anxiety, stress and pain.
这听起来很有希望。不过，这些受试者盖重毯时并没有睡得更久。而且，仅凭一晚的试验很难说明长期使用效果。因此，2024年发表在《BMC精神病学》上的一项更大规模试验，对95名确诊失眠的中国成年人进行了一个月的跟踪。每人被随机分配一条重5.5公斤或3.5公斤的毯子。一台设备记录了他们第一周的醒来次数。使用较重毯子的人醒来次数更少——但只是略少。试验结束时，两组在衡量失眠严重程度的问卷上得分都有改善，但改善幅度在统计上无法区分。不过，在涉及睡眠质量及相关问题的其他问卷上，两组出现了分化。使用较重毯子的受试者报告，整体睡眠质量的改善幅度约为另一组的两倍，疲劳、焦虑、压力和疼痛的减轻也更明显。