Article

Age-related decline in physical capabilities may lead to older adults
experiencing difficulty in performing everyday activities due to high demands
placed on the muscles of their lower extremity. This study aimed to determine the
biomechanical functional demand in terms of joint moments and maximal muscle
capabilities at the knee and hip joints while older adults performed stair ascent
(SA) and stair descent (SD). Eighty-four healthy older adults aged 60-88 years
were tested. A torque dynamometer attached to a purpose-built plinth was utilized
to measure muscle moments at the knee and hip joints. Participants also underwent
full body 3-D biomechanical assessment of stair ascent and descent using an
8-camera VICON system (120Hz) with 3 Kistler force plates. Stair negotiation
required knee extensor moments in excess of the maximum isometric muscle strength
available (SA 103%, SD 120%). For the hip, the levels of demand were high, but
were slightly lower than those of the knee joint. Stair negotiation placed a high
level of demand on the knee extensors with demand in SA reaching maximal
isometric capacity and demand in SD exceeding maximal isometric capacity. The
levels of demand leave little reserve capacity for the older adult to draw on in
unexpected situations or circumstances.
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Langue : ANGLAIS