Obstacle negotiation kinematics: age-dependent effects of postural threat
McKenzie, Nicole C.
University of Lethbridge. Faculty of Arts and Science
Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2002
The effects of postural threat and the potential consequences of obstacle contact on the obstacle contact on the obstacle negotiation kinematics among younger and older adults were examined. Seventeen older (OA;7males, 10 females; mean age, 68.94 + 4.85) and fifteen younger adults (YA; 5males, 10 females; mean age, 22.53 + 2.77) negotiated virtual and real obstacles while walking at a self-determined velocity along a 7.2m walkway under 4 different conditions of postural threat. Postural threat was manipulated by varying the width (0.60m)) of the walkway. Postural threat altered crossing kinematics for all subjects. Specifically, age-related differences emerged with increasing postural threat, however the changes observed among older adults were considerably different from those of younger adults. Additionally, there was no effect for the potential consequences of obstacle contact, however, no age-related differences emerged. These results revealed an effect for postural threat and obstacle characteristics on the negotiation strategies of younger and older adults. Both postural threat and obstacle characteristics elicit conservative crossing kinematics in younger and older adults. Specifically, these findings illustrate age-dependent differences in obstacle negotiation strategies and that postural threat affects older adults differently than younger adults whereas the potential consequences of obstacle contact affects younger and older adults equally.
xii, 79 leaves ; 28 cm.
Posture , Kinesiology , Human locomotion , Dissertations, Academic