{"668623":{"#nid":"668623","#data":{"type":"event","title":"BioE PhD Defense Presentation- Lindsey Trejo","body":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EZoom Link:\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/strong\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E \u003Ca href=\u0022https:\/\/gatech.zoom.us\/j\/5374686038\u0022\u003Ehttps:\/\/gatech.zoom.us\/j\/5374686038\u003C\/a\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EAdvisor:\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/strong\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EGreg Sawicki, Ph.D. (Georgia Institute of Technology)\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003E\u003Cspan\u003EThesis Committee:\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/strong\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EYoung-Hui Chang, Ph.D. (Georgia Institute of Technology)\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EYoung Jang, Ph.D. (Georgia Institute of Technology)\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003ESabrina Lee, Ph.D. (Simon Fraser University)\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003ERich Mahoney, Ph.D. (Intuitive)\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u0026nbsp;\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003EInteraction of ankle exoskeleton assistance with age-related changes in physiology to reduce metabolic cost of walking\u003C\/span\u003E\u003C\/strong\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EDifficulties with mobility were the most commonly reported disability for those age 65 and over. It is well known that older adults are slower and less economical during walking compared to young. This is thought to be brought on by reduced ankle push off power and a redistribution of positive power generation to more proximal joints (e.g., hip). Ankle exoskeletons have been shown to increase ankle push off, increase self-selected speed, and reduce metabolic cost in young adults for a near immediate improvement in walking performance. There is a\u0026nbsp;\u003Cem\u003Ecritical gap\u003C\/em\u003E\u0026nbsp;in understanding whether beneficial exoskeleton assistance strategies for younger adults will also benefit older adults and if so, what the underlying mechanism is that enables exoskeletons to reduce metabolic cost across age.\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EOlder adults have more compliant tendons than young, or a less stiff spring, operate with shorter less optimal muscle lengths, and exhibit reduced push-off power leading to a loss of the \u2018spring in their step\u2019. This necessitates higher muscle activations and reliance on muscles at less efficient joints like the hips, increasing metabolic cost during walking. Passive ankle exoskeletons have been shown in younger adults to lower the demand at the ankle, optimize complicated muscle-tendon dynamics during stance, and reduce metabolic cost. Muscle level changes in young adults in response to ankle exoskeletons to reduce metabolic cost led to wondering how ankle exoskeletons interact with age-related changes in physiology to reduce metabolic cost. The near-term \u003Cem\u003Eobjective \u003C\/em\u003Eof my work was to evaluate the calf muscles and tendon\u2019s role in modifying metabolic cost during walking with passive, and active ankle exoskeletons across age. My\u0026nbsp;central \u003Cem\u003Ehypothesis\u0026nbsp;\u003C\/em\u003Ewas ankle exoskeletons can offset age-related changes in physiology to reduce metabolic cost to that of young walking economy.\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\r\n\r\n\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003EI used electromyography to measure muscle activity, B-mode ultrasound to track muscle level changes, and a portable indirect calorimetry system to measure metabolic cost in young and older adults with passive and active exoskeleton conditions. These aims yielded a greater understanding of how people interact with ankle exoskeletons to modify metabolic cost. These outcomes can improve the design and control of ankle exoskeletons to improve the cost of walking across age, leading to greater mobility and increased quality of life. The aims also clarified whether passive or active control is best for young or older adults. Passive devices are lighter weight, require less maintenance, and are easier to conceal but they are less tunable and have shown lower reductions in metabolic cost. Active devices can be optimized for each person and provide more assistance at any timepoint in the gait cycle. However, motors and batteries make a lightweight device difficult to create and complicates usage with maintenance, battery life, bulkiness, and noise. Completion of the aims, pave the way for studies in more functional measures such as increasing self-selected walking speed, improving balance, and reducing fatigue that may translate more directly to improved quality of life.\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n","summary":"","format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cspan\u003E\u003Cstrong\u003E\u003Cspan\u003EBioE PhD Defense Presentation \u0022Interaction of ankle exoskeleton assistance with age-related changes in physiology to reduce metabolic cost of walking\u0022\u0026nbsp;- Lindsey Trejo \u003C\/span\u003E\u003C\/strong\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/span\u003E\u003C\/p\u003E\r\n","format":"limited_html"}],"field_summary_sentence":[{"value":"\u0022Interaction of ankle exoskeleton assistance with age-related changes in physiology to reduce metabolic cost of walking\u0022"}],"uid":"27917","created_gmt":"2023-07-27 20:09:34","changed_gmt":"2023-07-27 20:09:34","author":"Laura Paige","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2023-08-14T15:00:00-04:00","event_time_end":"2023-08-14T17:00:00-04:00","event_time_end_last":"2023-08-14T17:00:00-04:00","gmt_time_start":"2023-08-14 19:00:00","gmt_time_end":"2023-08-14 21:00:00","gmt_time_end_last":"2023-08-14 21:00:00","rrule":null,"timezone":"America\/New_York"},"location":"GTMI Room 114","extras":[],"groups":[{"id":"65448","name":"Bioengineering Graduate Program"}],"categories":[],"keywords":[{"id":"172056","name":"go-BioE"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}