Background

Running is a popular activity practiced worldwide. It is important to understand how running affects joint health to provide recommendations to sports medicine practitioners and runners.

Objective

Our aim was to summarize the influence of running on lower limb cartilage morphology and composition using quantitative magnetic resonance imaging (MRI).

Methods

Prospective repeated-measures studies evaluating cartilage using MRI before and after running were included. Data sources included Pubmed, Embase, CINAHL, SportDiscus, Web of Science, and Cochrane Central Registry of Controlled Trials. Qualitative analyses considered the number and methodological quality ratings of studies based on the QualSyst tool, and recommendations were based on the strength of evidence (strong, moderate, limited, or very limited). Quantitative analysis involved meta-analyses, for which effect sizes were calculated as Hedge’s g standardized mean differences.

Results

We included 43 articles, assessing seven outcomes (lesions, volume, thickness, glycosaminoglycan content, and T1ρ, T2, and T2* relaxation times). Nineteen articles were rated as high quality, 24 were rated as moderate quality, and none were rated as low quality. Qualitative analyses suggest that running may cause an immediate reduction in knee cartilage volume, thickness, as well as T1ρ and T2 relaxation times immediately; however, these changes did not persist. Meta-analyses revealed a small and moderate decrease immediately following a single running bout in T2 relaxation time in the medial femur and tibia, respectively. Qualitative analyses indicated that the influence of repeated exposure to running on cartilage morphology and composition was limited. Despite conflicting evidence regarding pre-existing knee cartilage lesions, moderate evidence suggests that running does not lead to the formation of new lesions. Repeated running exposure did not cause changes to foot and ankle cartilage thickness or composition.

Conclusions

Changes to lower limb cartilage following running are transient. Immediate changes to cartilage morphology and composition, which likely reflect natural fluid dynamics, do not persist and were generally not significant when pooled statistically. Results suggest that cartilage recovers well from a single running bout and adapts to repeated exposure. Given that moderate evidence indicates that running does not lead to new lesions, future trials should focus on clinical populations, such as those with osteoarthritis.

Trial Registration

Not applicable.

中文翻译：

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跑步对下肢软骨的影响：系统评价和荟萃分析

背景

跑步是一项全球流行的活动。了解跑步如何影响关节健康以向运动医学从业者和跑步者提供建议非常重要。

客观的

我们的目的是使用定量磁共振成像 (MRI) 总结跑步对下肢软骨形态和成分的影响。

方法

包括在跑步前后使用 MRI 评估软骨的前瞻性重复测量研究。数据来源包括 Pubmed、Embase、CINAHL、SportDiscus、Web of Science 和 Cochrane Central Registry of Controlled Trials。定性分析考虑了基于QualSyst工具的研究数量和方法学质量评级，建议基于证据强度（强、中、有限或非常有限）。定量分析涉及荟萃分析，其影响大小计算为 Hedge 的 g 标准化平均差。

结果

我们纳入了 43 篇文章，评估了七种结果（病变、体积、厚度、糖胺聚糖含量和 T1ρ、T2 和 T2* 弛豫时间）。19篇文章被评为高质量，24篇被评为中等质量，没有一篇被评为低质量。定性分析表明，跑步可能会立即导致膝关节软骨体积、厚度以及 T1ρ 和 T2 松弛时间立即减少；然而，这些变化并没有持续下去。Meta 分析显示，在单次跑步后，股骨内侧和胫骨的 T2 弛豫时间分别出现小幅和中度下降。定性分析表明，反复跑步对软骨形态和成分的影响是有限的。尽管关于预先存在的膝关节软骨损伤的证据相互矛盾，适度的证据表明，跑步不会导致新病变的形成。反复跑步暴露不会导致脚和脚踝软骨厚度或成分发生变化。

结论

跑步后下肢软骨的变化是短暂的。可能反映自然流体动力学的软骨形态和组成的即时变化不会持续存在，并且在统计汇总时通常不显着。结果表明，软骨从单次跑步中恢复良好，并适应反复暴露。鉴于适度的证据表明跑步不会导致新的损伤，未来的试验应该关注临床人群，例如患有骨关节炎的人群。

试用注册

不适用。