Though the study mentioned above was fairly small (only 191 women took the initial fitness test, which means it's hard to maintain statistical significance while breaking the group down into sub-categories of more or less fit), it does give us hope that dementia can be prevented or delayed through exercise in one's middle age.
尽管上述研究的规模相当有限(最初只有191名女性接受了体能测试,这意味着如果再按体能水平将参与者细分为更健康和不太健康的亚组,就很难保持统计学显著性),但它确实让我们看到希望:人在中年时期通过锻炼,或许能够预防或延缓痴呆症的发生。
该分句由"Though"引导,说明研究规模较小这一事实与主句中的希望形成让步关系,整体修饰主句。