敏捷訓練對於輕微認知受損年長者的敏捷能力、身體表現、認知功能以及腦部活化之影響

Abstract

背景：隨著年齡增長，年長者的認知和身體功能皆有可能顯著下降，輕微認知受損近年來是一個備受關注的族群。輕微認知受損為介於正常認知老化和失智症之間的過渡狀態，可能對年長者執行較複雜的日常生活功能造成影響，並增加發展為失智症的風險。為了應對這些挑戰，探索有效的介入訓練至關重要;敏捷訓練作爲一種結合快速全身性運動以及速度和方向變化的運動訓練，似乎有潛力改善年長者的身體與認知功能。過去這種訓練方式大多應用於運動員或年輕人，但近年研究表明，敏捷訓練可能提升年長者的神經肌肉表現、動態平衡和認知功能。本研究旨在評估敏捷訓練對於輕微認知受損年長者動作與認知表現的影響，強調其減緩與老化相關衰退的潛力。

研究目的：探討敏捷訓練對於改善輕微認知受損年長者的身體功能、認知功能與腦部活化之成效。

研究方法：本研究共招募30位輕微認知受損之年長者，於訓練前、訓練後以及訓練結束後一個月（追蹤）共三個時間點進行評估。評估項目包含：敏捷表現、動作功能（行走表現、耐力、平衡、肌力與爆發力）、認知功能（整體認知、工作記憶、認知轉換、選擇性注意與抑制控制），同時使用功能性近紅外光頻譜儀量測腦部活化情形。受試者於前測後隨機分配至敏捷訓練組或控制組。控制組接受為期8週的健康教育指導，包括居家運動建議、老年人飲食建議與預防跌倒相關知識；敏捷訓練組則進行每週兩次、每次60分鐘、一對一的敏捷訓練，共持續8週。訓練內容涵蓋三種不同的環境配置與多樣化指令的敏捷任務，並依據受試者執行情況調整訓練強度與難度。訓練結束後一週內進行後測，並於一個月後實施追蹤測試。

結果：本研究共納入30位受試者，17位受試者分配至敏捷訓練組 (AG)、13位分配至控制組 (CG)。八週訓練後，敏捷表現出現顯著的組別 × 時間交互作用，F(1.65, 46.15) = 5.49，p = 0.007，partial η² = 0.164，其中AG呈現顯著進步（ACE總耗時由72.4 ± 8.8秒降至62.2 ± 8.9秒，p < 0.001）。在雙重任務行走下的步長亦呈現顯著的組別 × 時間交互作用，F(2, 56) = 4.65，p = 0.014，partial η² = 0.142。此外，在單一任務與雙任務行走的步速與步長，以及6分鐘行走距離，均出現顯著的時間主效應（p < 0.05）。認知表現方面，整體認知功能呈現顯著時間主效應，F(1.36, 38.08) = 20.43，p < 0.001，partial η²= 0.422，AG的MoCA分數自24.2 ± 1.3提升至27.2 ± 3.4（p < 0.001）。選擇性注意力也有改善（Stroop一致條件反應時間：F(1.53, 41.38) = 3.25，p = 0.046，partial η²= 0.107）、抑制控制能力提升（Stroop不一致條件反應時間：F(2, 54) = 8.55，p = 0.001，partial η² = 0.241），以及認知轉換能力的進步（WCST錯誤率：F(2, 54) = 3.29，p = 0.044，partial η² = 0.105）。雖然腦部活化方面的結果均未觀察到顯著變化，AG在敏捷任務中展現出前額葉皮質活化下降，並於SMA與PMC呈現活化上升，在雙重任務行走中亦維持這些區域的活化。此外，在認知任務中AG表現出較穩定的前額葉參與，表示可能有神經效率提升的作用產生。

總結：敏捷訓練可有效提升輕微認知受損年長者的敏捷表現、步態功能與整體認知功能，並可能促進與動作-認知整合相關的腦部活化調節。

Background: The aging population is experiencing a notable decline in both cognitive and physical functions, with Mild Cognitive Impairment (MCI) emerging as a significant concern. MCI is a transitional state between normal cognitive aging and dementia, potentially affecting daily living and increasing the risk of progression to dementia. To address these challenges, exploring effective interventions is crucial. Agility training, which combines rapid whole-body movements with changes in speed and direction, has shown promise in improving both physical and cognitive functions. Though traditionally applied to athletes, recent studies suggest that agility training has the potential to enhance neuromuscular performance, dynamic balance, and cognitive function in older adults. This study aims to evaluate the effects of agility training on physical and cognitive function in older adults with MCI, emphasizing its potential to mitigate age-related declines and improve overall functioning.

Study purpose: The present study aims to investigate the effects of agility training on physical function, cognitive function and brain activities in elderly with MCI.

Method: The present study recruited 30 elderly individuals with MCI. Assessments were conducted at three points: pre-test, post-test, and one-month follow-up. These assessments evaluated agility, motor function (walking performance, endurance, balance, muscle power and muscle strength), cognitive functions (global cognition, working memory, mental-set shifting, selective attention, and inhibitory control), and brain activation (assessed by functional near-infrared spectroscopy, fNIRS). After the pre-test, participants were randomly assigned to an agility training group (AG) or a control group (CG). The CG received an 8-week health education guideline, which included home exercises, dietary recommendations for the elderly, and fall prevention education. The AG underwent agility training twice a week, for 60 minutes each session, over 8 weeks, conducted on a one-on-one basis. The agility training included three different environmental setups and agility exercises with varying instructions, while training intensity and difficulty was adjusted based on each participant's performance. The post-test was conducted within a week after the training ends and all the participants underwent a follow-up test one month later.

Results: Seventeen participants were assigned to the AG and 13 to the CG. After 8-week intervention, a significant group x time interaction was observed in agility performance, F(1.65, 46.15) = 5.49, p = 0.007, partial η² = 0.164, with the AG showing significant improvement (ACE total time: 72.4 ± 8.8 to 62.2 ± 8.9 s, p < 0.001). Stride length under dual-task walking also showed a significant group x time interaction, F(2, 56) = 4.65, p = 0.014, partial η² = 0.142. In addition, significant time main effects were found for gait speed and stride length under both single- and dual-task walking, as well as for 6-minute walk distance (p < 0.05). Regarding cognitive outcomes, a significant time main effect was observed for global cognition, F(1.36, 38.08) = 20.43, p < 0.001, partial η² = 0.422, with MoCA scores in the AG increasing from 24.2 ± 1.3 to 27.2 ± 3.4 (p < 0.001). Improvements were also found in selective attention (Stroop congruent reaction time: F(1.53, 41.38) = 3.25, p = 0.046, partial η² = 0.107), inhibitory control (Stroop incongruent reaction time: F(2, 54) = 8.55, p = 0.001, partial η² = 0.241), and mental set shifting (WCST error rate: F(2, 54) = 3.29, p = 0.044, partial η² = 0.105). While no significant effect was found in cortical HbO levels, the AG demonstrated activation in the PFC and increased activation in the SMA and PMC during the agility task, and sustained activation in these regions during dual-task walking. Moreover, more stable prefrontal engagement was observed across cognitive tasks in the AG, suggesting potential neural efficiency.

Conclusion: Agility training appears to be an effective intervention for improving agility, gait performance, and cognitive functions in older adults with MCI. It may also support adaptive brain activation patterns related to cognitive-motor integration.