利用人因方法評估不同揹負方式之生理與心物反應

The Ergonomic Evaluations of Physical and Psychophysical Responses among Different Carrying Methods

吳昭瑩(Chao-Tin Wu)

指導教授 ： 王茂駿 ； 張堅琦

國立清華大學/工學院/工業工程與工程管理學系/博士(2016年)

摘要

攜帶「襁褓」中的嬰兒與攜帶貨物（或私人物品）是兩大重要的攜帶功能。在現今繁忙的社會中，使用背負工具使人可以空出做家事或工作並且同時照顧嬰兒或攜帶物品。然而背負相關的文獻多著墨在背負重量(如背包、書包等)，背負時的速度與背負嬰兒的相關研究幾乎無人探究。本研究目的在於找出男性與女性在使用背包或嬰兒背帶時的生理與心理反應，以及生物力學的差異。
本研究分為兩個部分，第一個部分為比較男女在使用傳統嬰兒背帶與兩款一般具有背包特性的背帶之生理與心理反應資訊。實驗共招募10位女性與10位男性。受試者背負兩種不同重量的嬰兒娃娃（7kg 與10kg）行走20分鐘。生理反應包含壓力、肌肉活動度、膚溫差及心搏差。心理反應則以Borg身體疲勞程度評比測得。數據分析結果顯示，三款嬰兒背帶在肩部平均壓力、肌肉活動度與心搏率（運動強度）上並無顯著差異。身體疲勞程度量表在頸部、左肩、右肩及上背對款式有顯著差異，其中以一款肩部帶子有軟墊的背帶表現較另兩款好。而在不同嬰兒重量下，肌肉活動度與肩部平均壓力則有不同。男女的差異則顯示在肌肉活動度上，男性使用較多肩部的力量而女性使用較多腰部的力量。根據實驗結果，對於傳統背帶與背帶設計提出相關建議，以期得到符合使用者期望的產品。
第二部分的研究則是針對男女在一般後背包使用不同重量與不同行走速度時的差異。實驗共招募20位受試者（10位女性與10位男性），此階段在測量男女在不同背包重量與行走速度時的步態相關與心理主觀反應的差異。步態相關反映包括步長，步數，兩腳著地時間，行走時下肢關節角度變化，地面反作用力，肌肉活動度。心理主觀反應則使用Borg身體疲勞程度評比測得。受試者背負不同重量（0%, 10%, 15% 與 20% 體重） 與不同速度 （80%, 100% 與120% 最適行走速度）共12個實驗組合下，測試立即效果。 結果顯示重量在背負行走中是比較主要的影響因子，重量越重近端關節（骨盆與髖關節）相較於遠端關節（膝關節與踝關節）有較大的改變，腹直肌活動度增加但背直肌活動度減少。主觀反應也顯示隨著重量增加肩頸上背的主觀疲勞程度增加。而男女在不同走路速度與負重情況下的反應主要顯示在骨盆的活動度上，女性的骨盆活動度在矢狀面比較小，而在額狀面比較大。根據此研究結果提供了背包重量的建議，並且針對不同性別提出不同的負重訓練建議。

關鍵字

嬰兒背帶 ； 背包 ； 壓力 ； 肌電圖 ； 膚溫 ； Borg量表 ； 關節角度 ； 地面反作用力

並列摘要

Care of pre-weaned infants and transporting goods (or personal belongings) were the two major function of carrying activity. In today’s busy world, using carrying devices could free the hands of the person and help them to manage the daily activities while taking care of their baby or carrying their goods. Studies regarding carrying were mostly focused on backpack weight. There were few study investigated walking speed or baby carrier effects. The purpose of this study was to investigate the physiological and biomechanical responses in men and women while carrying the baby or backpack.
The first study compared gender differences using the baby sling and front worn harness carrier in the physiological and psychophysical responses. Ten females (aged 23-32 years) and ten males (aged 23-35 years) were recruited to participate in this study. Each subject was asked to carry two different weighted baby dummies (7kg and 10kg) using 3 different baby carriers and walk for 20 minutes. Body tactile pressures were measured. The physiological responses, which were recorded during walking included average surface electromyography (sEMG), skin temperature change, heart rate change and exercise intensity. Immediately after walking, the Borg’s rating scale of perceived exertion was used to collect the psychophysical responses. The traditional baby sling and the two front worn harness carrier showed little differences in sEMG activities, body tactile pressure and exercise intensity. Carrying two different weighted baby dummies caused significant differences in sEMG and body tactile pressure. Gender differences were found in sEMG activities, where men used more upper back muscles and women used more low back muscles. Based on the findings of this study, recommendations about the improved baby carrier design are proposed.
The second study examined the backpack load effect on gender walking gait and speed parameters. Twenty subjects (10 males, 10 females) with ages ranging from 21-28 years were involved in a backpack carrying task. The load was specified at 0%, 10%, 15% and 20% of their body weight. The three walking speed levels included preferred walking speed (PWS), 80% PWS and 120% PWS. The response measures included lower extremity joint motion, surface electromyography (sEMG) activities and ground reaction force (GRF) during walking. The results indicated that the load effect was a dominant factor. The increase in backpack weight produced a decrease in pelvis anterior tilt, hip extension and an increase in pelvis posterior tilt. The rectus abdominis muscle activity increased, but the erector spinae and semitendinosus activities decreased with increasing backpack weight. The vertical GRF component increased with the increase in backpack weight. Shoulder area perceived exertion discomfort was the highest at 20% BW load. Post hoc test results showed less difference between 10% BW and 15% BW, but greater differences between 20% BW and the lower weights. Gender differences were found in pelvic ROM, where women had smaller ROM in sagittal plane but larger ROM in frontal plane. In conclusion, people used different muscles with a change in gait pattern to accommodate a heavier backpack. The results from this study provide very useful recommendations for backpack weight and training recommendations for different gender.

並列關鍵字

Baby Carrier ； Backpack ； Body Tactile Pressure ； EMG ； Skin Temperature ； Borg’s CR-10 Scale ； ROM ； GRF ； Preferred Walking Speed

參考文獻

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