Rice Hannah, Patel Mubarak
Sport and Health Sciences, University of Exeter, Exeter, UK.
Vibration Engineering Section, College of Engineering, Mathematics and Physical Sciences, Streatham Campus, University of Exeter, Exeter, UK.
Am J Sports Med. 2017 Aug;45(10):2411-2417. doi: 10.1177/0363546517704429. Epub 2017 May 1.
The Achilles tendon is the most common site of tendon overuse injury in humans. Running with a forefoot strike pattern and in minimal shoes is a topic of recent interest, yet evidence is currently limited regarding the combined influence of foot strike and footwear on Achilles tendon loading.
To investigate the influence of both foot strike and footwear on Achilles tendon loading in habitual rearfoot strike runners.
Controlled laboratory study.
Synchronized kinematic and force data were collected from 22 habitual rearfoot strikers (11 male), who habitually ran in nonminimal running shoes, during overground running at 3.6 m·s. Participants ran in 3 different footwear conditions (standard running shoe, minimal running shoe, and barefoot) with both a rearfoot strike (RFS) and an imposed forefoot strike (FFS) in each footwear condition. Achilles tendon loading was estimated by use of inverse dynamics, where the Achilles tendon moment arm was determined with a regression equation. A 2-way, repeated-measures analysis of variance was used to compare conditions.
Achilles tendon impulse was greater when subjects ran with an FFS rather than an RFS in minimal shoes. Achilles tendon loading rates were higher when subjects ran either in minimal shoes or barefoot than in standard shoes, regardless of foot strike.
In runners who habitually rearfoot strike in standard running shoes, running in minimal shoes or barefoot increased the rate of tendon loading, and running with a forefoot strike in minimal shoes increased the magnitude of tendon loading.
Transitioning to these running conditions may increase the risk of tendinopathy.
跟腱是人类肌腱过度使用损伤最常见的部位。前脚掌着地跑步和穿极简跑鞋是近期备受关注的话题，但目前关于着地方式和鞋类对跟腱负荷的综合影响的证据有限。
研究着地方式和鞋类对习惯性后脚掌着地跑步者跟腱负荷的影响。
对照实验室研究。
从22名习惯性后脚掌着地跑步者（11名男性）收集同步运动学和力数据，这些跑步者习惯穿非极简跑鞋在地面以3.6米/秒的速度跑步。参与者在3种不同的鞋类条件下跑步（标准跑鞋、极简跑鞋和赤足），每种鞋类条件下既有后脚掌着地（RFS），也有强制前脚掌着地（FFS）。通过逆动力学估计跟腱负荷，其中跟腱力臂用回归方程确定。采用双向重复测量方差分析比较不同条件。
当受试者在极简跑鞋中以FFS跑步时，跟腱冲量比RFS时更大。无论着地方式如何，受试者在极简跑鞋或赤足跑步时的跟腱负荷率均高于穿标准跑鞋时。
在习惯穿标准跑鞋后脚掌着地的跑步者中，穿极简跑鞋或赤足跑步会增加肌腱负荷率，在极简跑鞋中前脚掌着地跑步会增加肌腱负荷量。
转变为这些跑步条件可能会增加肌腱病的风险。
