A progressive decline in maximum heart rate (mHR) is a fundamental aspect of aging in humans and other mammals. This decrease in mHR is independent of gender, fitness, and lifestyle, affecting in equal measure women and men, athletes and couch potatoes, spinach eaters and fast food enthusiasts. Importantly, the decline in mHR is the major determinant of the age-dependent decline in aerobic capacity that ultimately limits functional independence for many older individuals. The gradual reduction in mHR with age reflects a slowing of the intrinsic pacemaker activity of the sinoatrial node of the heart, which results from electrical remodeling of individual pacemaker cells along with structural remodeling and a blunted β-adrenergic response. In this review, we summarize current evidence about the tissue, cellular, and molecular mechanisms that underlie the reduction in pacemaker activity with age and highlight key areas for future work.

中文翻译：

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心脏起搏器活动和衰老。

最大心率（mHR）逐渐下降是人类和其他哺乳动物衰老的一个基本方面。mHR 的下降与性别、健康状况和生活方式无关，对女性和男性、运动员和电视迷、吃菠菜的人和快餐爱好者都有同样的影响。重要的是，mHR 的下降是年龄依赖性有氧能力下降的主要决定因素，最终限制了许多老年人的功能独立性。mHR 随着年龄的增长而逐渐降低，反映了心脏窦房结内在起搏器活动的减慢，这是由于单个起搏器细胞的电重塑以及结构重塑和 β-肾上腺素能反应减弱所致。在这篇综述中，我们总结了有关起搏器活动随着年龄增长而减少的组织、细胞和分子机制的当前证据，并强调了未来工作的关键领域。