Kwee-Meier Sonja Th, Mertens Alexander, Jeschke Sabina
Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Bergdriesch 27, 52062 Aachen, Germany.
Institute of Industrial Engineering and Ergonomics, RWTH Aachen University, Bergdriesch 27, 52062 Aachen, Germany.
Gait Posture. 2018 May;62:490-496. doi: 10.1016/j.gaitpost.2018.04.003. Epub 2018 Apr 12.
Uphill walking is particularly challenging for elderly persons. However, there is a lack of age-differentiated studies investigating the underlying differences in muscle activation when walking on sloped surfaces. These studies are needed, e.g., for planning of evacuations of large modern cruise ships with long walking distances on often inclined surfaces.
An age-differentiated, gender-balanced study with 26 young (20-30 years) and 26 elderly people (60-77 years) was therefore conducted, investigating uphill walking at 7° and at 14° contrasted to level walking on a treadmill. EMG signals of musculus gluteus maximus (GMAX), m. biceps femoris (BF), m. rectus femoris (RF), m. vastus medialis (VM), m. gastrocnemius medialis (GAS) and m. soleus (SOL) were analysed with regard to mean and maximum muscle activities and timing during the gait cycle.
The results showed that walking uphill at 14° was highly strainful for elderly people. In line with previous research, young people mostly "pushed" themselves uphill with the GAS and SOL. In contrast, elderly people not only used the known compensatory ability of hip muscles to propel the trailing leg, but also showed a high level of BF activation prolonged until the mid-stance phase at the steepest uphill gradient of 14°.
The strikingly long activation of the BF until the mid-stance phase in elderly people at steep gradients is an unexpected, new finding. It suggests that, instead of pushing, elderly people "pull" themselves uphill. In cases of evacuations, the lower physical fitness levels of elderly passengers and their increased need for assistance on inclined surfaces have to be planned for in advance. Considering the findings in (home) training programmes might help elderly people to strengthen lower limb muscles and to enhance the efficiency of muscle activation patterns enabling them to manage steep inclinations more easily.
上坡行走对老年人来说尤其具有挑战性。然而，缺乏针对不同年龄段的研究来探究在倾斜表面行走时肌肉激活的潜在差异。例如，在规划大型现代游轮的疏散时，由于在经常倾斜的表面上行走距离较长，就需要这类研究。
因此，开展了一项针对不同年龄段、性别均衡的研究，研究对象包括26名年轻人（20 - 30岁）和26名老年人（60 - 77岁），调查在跑步机上以7°和14°坡度上坡行走与水平行走的差异。分析了臀大肌（GMAX）、股二头肌（BF）、股直肌（RF）、股内侧肌（VM）、腓肠肌内侧头（GAS）和比目鱼肌（SOL）的肌电图信号，以了解步态周期中的平均和最大肌肉活动以及时间。
结果表明，以14°坡度上坡行走对老年人来说压力极大。与先前的研究一致，年轻人大多通过腓肠肌内侧头和比目鱼肌“推”自己上坡。相比之下，老年人不仅利用了髋部肌肉已知的代偿能力来推动后摆腿，而且在14°最陡上坡坡度时，股二头肌的激活水平很高，且一直持续到站立中期。
在陡坡时老年人股二头肌直到站立中期的显著长时间激活是一个意外的新发现。这表明，老年人不是“推”自己上坡，而是“拉”自己上坡。在疏散情况下，必须提前考虑老年乘客较低的身体素质水平以及他们在倾斜表面上对援助的更多需求。在（家庭）训练计划中考虑这些发现可能有助于老年人增强下肢肌肉，并提高肌肉激活模式的效率，使他们能够更轻松地应对陡坡。
