The impact of mid-late-life exercise on the aging heart remains unclear, particularly the effects of high-intensity interval training (HIIT) and continuous moderate-intensity training (CMIT). This study was the first to examine cardiac function, tissue characteristics, electrical remodeling, mitochondrial morphology and homeostasis in old mice subjected to CMIT or HIIT, compared to untrained controls. Our results showed that 8-week HIIT significantly improved the survival rate of old mice. HIIT presented advantages on cardiac function, deposition of collagen fibers, neovascularization, aging biomarkers and mitochondrial homeostasis. Only CMIT alleviated age-related cardiac hypertrophy. However, CMIT potentially exacerbated adverse cardiac electrical remodeling. Those findings suggested HIIT as a particularly appealing option for clinical application for aging populations.

中文翻译：

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中晚期高强度间歇训练与持续中等强度训练对老年小鼠心脏的影响比较


中晚年运动对衰老心脏的影响尚不清楚，尤其是高强度间歇训练 （HIIT） 和持续中等强度训练 （CMIT） 的影响。与未经训练的对照相比，这项研究首次检查了接受 CMIT 或 HIIT 的老年小鼠的心脏功能、组织特征、电重塑、线粒体形态和体内平衡。我们的结果表明，8 周 HIIT 显着提高了老年小鼠的存活率。HIIT 在心脏功能、胶原纤维沉积、新生血管形成、衰老生物标志物和线粒体稳态方面具有优势。只有 CMIT 减轻了与年龄相关的心脏肥大。然而，CMIT 可能会加剧不良的心脏电重构。这些发现表明 HIIT 是老龄化人群临床应用的特别有吸引力的选择。