Stenroth Lauri, Sillanpää Elina, McPhee Jamie S, Narici Marco V, Gapeyeva Helena, Pääsuke Mati, Barnouin Yoann, Hogrel Jean-Yves, Butler-Browne Gillian, Bijlsma Astrid, Meskers Carel G M, Maier Andrea B, Finni Taija, Sipilä Sarianna
Gerontology Research Center and Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland. Department of Biology of Physical Activity, Neuromuscular Research Center, University of Jyvaskyla, Jyvaskyla, Finland.
Gerontology Research Center and Department of Health Sciences, University of Jyvaskyla, Jyvaskyla, Finland.
J Gerontol A Biol Sci Med Sci. 2015 Aug;70(8):996-1002. doi: 10.1093/gerona/glv011. Epub 2015 Mar 1.
Muscle mass, strength, and power are known determinants of mobility in older adults but there is limited knowledge on the influence of muscle architecture or tendon properties on mobility. The purpose of this study was to examine the relationship between mobility and plantarflexor muscle-tendon properties in healthy older adults.
A total of 52 subjects (age 70-81 years) were measured for 6-minute walk test (6MWT), timed "up and go"-test (TUG), isometric plantarflexion strength, Achilles tendon stiffness, triceps surae muscle architecture, lower extremity lean mass, isometric leg extension strength, and leg extension power. Partial correlations and multivariate regression models adjusted for sex, age, body mass, and height were used to examine the relationship between mobility (6MWT and TUG) and lower limb muscle-tendon properties.
Multivariate regression models revealed that Achilles tendon stiffness (p = .020), plantarflexion strength (p = .022), and medial gastrocnemius fascicle length (p = .046) were independently associated with 6MWT. Plantarflexion strength (p = .037) and soleus fascicle length (p = .031) were independently associated with TUG.
Plantarflexor muscle-tendon properties were associated with mobility in older adults independent of lower extremity lean mass, leg extension strength, or power. Plantarflexion strength was a stronger predictor of mobility than leg extension strength or power. The novel finding of this study was that muscle architecture and tendon properties explained interindividual differences in mobility. This study highlights the importance of the plantarflexors for mobility in older adults and provides understanding of possible mechanisms of age-related decline in mobility.
肌肉质量、力量和功率是老年人活动能力的已知决定因素，但关于肌肉结构或肌腱特性对活动能力的影响，人们了解有限。本研究的目的是探讨健康老年人的活动能力与跖屈肌肌腱特性之间的关系。
共对52名受试者（年龄70 - 81岁）进行了6分钟步行试验（6MWT）、定时起立行走试验（TUG）、等长跖屈力量、跟腱刚度、小腿三头肌肌肉结构、下肢瘦体重、等长腿伸展力量和腿伸展功率的测量。使用经性别、年龄、体重和身高调整的偏相关和多元回归模型，来研究活动能力（6MWT和TUG）与下肢肌肉肌腱特性之间的关系。
多元回归模型显示，跟腱刚度（p = .020）、跖屈力量（p = .022）和腓肠肌内侧肌束长度（p = .046）与6MWT独立相关。跖屈力量（p = .037）和比目鱼肌肌束长度（p = .031）与TUG独立相关。
跖屈肌肌腱特性与老年人的活动能力相关，且独立于下肢瘦体重、腿伸展力量或功率。跖屈力量比腿伸展力量或功率更能预测活动能力。本研究的新发现是，肌肉结构和肌腱特性解释了个体间活动能力的差异。本研究强调了跖屈肌对老年人活动能力的重要性，并提供了对与年龄相关的活动能力下降可能机制的理解。
