Fitness, Ageing, and Bilingualism (FAB): The Benefits of Regular Exercise and Bilingualism for Language Abilities in Healthy Ageing.
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 233
- 试验地点
- 2
- 主要终点
- Aerobic fitness - VO₂peak
研究概览
简要总结
This project investigates the relative benefits of regular physical activity and bilingualism for ameliorating cognitive decline in healthy ageing, with a particular focus on language function. The randomized intervention component tests whether improving fitness via a home-based HIIT program leads to changes in fitness and related cognitive/language outcomes in older adults.
详细描述
This project will determine the relative benefits of regular physical activity and bilingualism for the amelioration of cognitive decline in old age. Our project focuses on language because it is a core aspect of human cognition, which has received surprisingly little attention in ageing research given its tremendous impact on well-being. Our own previous research has demonstrated that healthy older adults experience a decline in language function, which is characterized by word finding difficulties, slower and more disfluent sentence production, and slower and less accurate sentence comprehension. Such language problems impact older adults' functioning and can lead to social withdrawal and loneliness. The current project, therefore, investigates how to ameliorate such language problems, as well as other forms of cognitive decline in healthy ageing. Two ameliorating factors that have received a lot of attention are bilingualism and regular physical activity, which have been shown to reduce the structural and functional brain decline associated with healthy ageing and to confer cognitive reserve, i.e. resilient cognitive performance. Currently, however, it has only been established that bilingualism and regular physical activity provide benefits for non-linguistic aspects of cognition, such as executive functioning, working memory, and processing speed. What is currently lacking is knowledge about the effects of exercise on language abilities in healthy ageing. Many language processes are isolated from, and independent of, other cognitive faculties. For example, word finding difficulties are not failures of long-term memory, as word knowledge increases with age, but the ability to successfully access words decreases. We have already demonstrated that fitter older adults experience fewer word finding difficulties than unfit older adults. In the current project, we aim to establish for the first time a causal relationship between physical exercise and ameliorated language decline in healthy ageing. To this end, we will conduct an aerobic exercise intervention and quantify increases in fitness levels and physical changes due to the intervention. We will examine the effects of these changes on language function in mono- and bilingual older adults. Moreover, using neuroimaging, we will investigate the neural changes underlying the benefits of exercise for language. Our study will thus provide new knowledge about how best to maintain language abilities across the lifespan. Furthermore, ameliorating language decline might be even more crucial for bilinguals than monolinguals, as bilingualism, even in young adults, has measurable costs for linguistic processing. Bilinguals have slower and less fluent word retrieval in both languages and more frequent word finding failures than monolinguals. Previous research provides competing accounts of these deficits, attributing them to either competition between languages during production or to the reduced frequency of use of a given language compared to monolinguals. Critically, these mechanisms may be differently affected by ageing. This is because with age, executive control declines, but language use accrues. Our research will therefore test these alternative theories about language decline in ageing bilinguals. We will also collect detailed information on the individual characteristics of bilinguals, which will allow us to identify those variables of bilingualism that serve to protect against decline in ageing. The study will be run across two institutions: the Universities of Agder (Norway) and Birmingham (UK).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Prevention
- 盲法
- None
入排标准
- 年龄范围
- 60 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Non-smokers for at least 5 years prior to enrollment.
- •Normal or corrected-to-normal vision and hearing.
- •No diagnosed language impairments (e.g., dyslexia, stuttering).
- •No illness or disease that would prevent safe participation in high-intensity interval training (HIIT).
- •Self-reported not meeting global physical activity recommendations (i.e., <150 minutes/week of moderate-intensity physical activity).
- •Norway only: Written health certificate from the participant's general practitioner confirming eligibility for participation.
排除标准
- •Any cardiovascular, metabolic, respiratory, neurological, kidney, liver, or cancer disease that would prevent safe participation in HIIT.
- •United Kingdom only: Severe electrocardiogram abnormalities (e.g., ST depression, long QT, heart block, wide QRS).
- •United Kingdom only: Elevated blood pressure at screening (systolic >160 mmHg and/or diastolic >90 mmHg).
研究组 & 干预措施
Exercise
Participants will complete a 26-week home-based HIIT program comprising simple circuit training once per week and interval training twice per week. A 26-week dose will be targeted; if interruptions occur (e.g., illness, travel), the intervention period will be extended to ensure completion of 26 weeks of exercise sessions. The first four weeks will constitute a familiarization period with sub-maximal sessions, training equipment familiarization (Polar Unite watch and Polar H9 chest sensor), and instructional videos. Subsequent sessions will target high intensity (≥80% of HRpeak). Training will be guided by a personal exercise coach via emails, phone calls, and face-to-face meetings once weekly during the familiarization period and monthly thereafter. Participants will use a Polar Unite watch and Polar H9 chest sensor; the watch will be pre-programmed to display %HRpeak in real time during sessions. Exercise data will be extracted using Polar Flow software.
干预措施: Home-Based HIIT (Other)
Control group
Control participants will be instructed to maintain their usual lifestyles without significant changes to physical activity or dietary habits.
结局指标
主要结局
Aerobic fitness - VO₂peak
时间窗: Baseline; 26 weeks (post-intervention)
Direct measurement of maximal oxygen uptake during a standardized progressive treadmill walking protocol to volitional fatigue. Participants complete 2-7 min self-paced level walking before the test. The test starts at 3.8 km/h with 4% incline; after a 4-min warm-up/stabilization, incline increases 3% every 4 min until blood lactate is 2.1 mmol/L above baseline, then incline increases 2% per minute up to 20%, followed by speed increases of 0.5 km/h per minute to exhaustion. VO₂peak is defined as the average of the highest 30-s VO₂ values. Test validity requires RER ≥ 1.10 or Borg ≥ 17.
Language function - Tip-of-the-tongue (TOT) task
时间窗: Baseline; 26 weeks (post-intervention)
Participants read definitions and attempt to name the target word (e.g., "A young swan" → "cygnet"). After each item they indicate Know, Don't Know, or Tip-of-the-tongue. The behavioral task includes 60 items (30 cognates; 30 non-cognates). Separate stimulus sets are used for English vs Norwegian, and for pre- vs post-intervention testing. Outcomes include probability of Know and TOT vs Don't Know (knowledge) and TOT vs Know (TOT probability).
Language function - sentence production (speeded picture description)
时间窗: Baseline; 26 weeks (post-intervention)
Speeded picture description to elicit phrases varying in type (coordinate vs prepositional clauses) and complexity (simple vs adjective-modified phrases). Stimuli comprise 20 image pairs, each appearing once in each of four conditions (within-items; within-subject). Outcomes include speech onset latency (RT) for correct responses and accuracy (correct clause produced). Separate stimulus sets are used for English pre, English post, Norwegian pre, and Norwegian post.
Cognitive function - working memory (n-back)
时间窗: Baseline; 26 weeks (post-intervention)
1-back and 2-back continuous performance task with 120 trials total (60 1-back; 60 2-back). Outcomes are reaction time and accuracy; incorrect includes misses/omissions as specified.
Language function - sentence comprehension (auditory word monitoring)
时间窗: Baseline; 26 weeks (post-intervention)
Participants make a speeded button press when they hear a pre-specified target word embedded in auditory input. Targets appear in unstructured lists, meaningful sentences with low target probability, and meaningful sentences with high target probability. Each stimulus set contains 60 items arranged across lists using a Latin square design. Outcome is reaction time measured from speech onset to button press for correct trials (and accuracy as applicable). Separate sets are used for English pre, English post, Norwegian pre, and Norwegian post.
Language function - discourse production (free picture description)
时间窗: Baseline; 26 weeks (post-intervention)
Participants describe one of four matched scenes inspired by the "cookie theft" picture (updated to include more objects/actions and less stereotyped roles). Primary outcome is speech duration (time speaking). Additional planned outcomes may include language complexity (e.g., mean phrase length, mean lexical frequency) and fluency (e.g., syllables per second, pausing-to-speech ratio). Scene presentation is counterbalanced to minimize repetition across sessions where applicable.
Language control - language switching (bilinguals only; cued picture naming)
时间窗: Baseline; 26 weeks (post-intervention)
Bilingual participants name pictures of common objects in L1 (Norwegian) or L2 (English) following a cue. 24 items appear across eight blocks: two English-only and two Norwegian-only blocks (single-language), plus four mixed blocks containing switch (L1↔L2) and stay trials. Two matched stimulus sets (pre and post) are used; order is counterbalanced. Outcomes include switching score (RT difference switch vs stay trials) and switching cost (RT difference switching vs non-switching blocks), plus accuracy.
Cognitive function - processing speed (letter comparison)
时间窗: Baseline; 26 weeks (post-intervention)
Same/different judgments for two letter strings presented top/bottom; string length varies from 3 to 6 letters, total 48 trials. Outcomes are reaction time and accuracy for correct responses.
Cognitive function - working memory (digit span)
时间窗: Baseline; 26 weeks (post-intervention)
Digits presented with 1-second inter-stimulus interval. Sequence length starts at 3 digits and increases up to 12. Each length is presented three times; participants must recall 2/3 correctly to continue. Task stops when criterion is not met. Outcome is maximum correctly recalled span (maximum 30 trials).
Cognitive function - attention/executive control (Attention Network Task; ANT)
时间窗: Baseline; 26 weeks (post-intervention)
Combined Posner cueing and flanker paradigm. Participants indicate direction of a central arrow flanked by congruent or incongruent arrows; cues indicate target location (top/bottom) after warning signal. 96 trials per block, 3 blocks total. Outcomes are ANT network indices: alerting (no cue RT - cue RT), orienting (center cue RT - spatial cue RT), and executive control (incongruent RT - congruent RT), computed for correct responses.
Cognitive function - task switching (colour-shape switching)
时间窗: Baseline; 26 weeks (post-intervention)
Four blocks: first/last are single-task ("solid") blocks (colour-only or shape-only), middle two are mixed blocks with switch/stay trials. Total 144 trials. Outcomes include RT and accuracy, plus local and global switch costs.
次要结局
- Aerobic fitness - blood lactate concentration(Baseline; 26 weeks (post-intervention))
- Physical function - handgrip strength(Baseline; 26 weeks (post-intervention))
- Physical function - 30-second chair stand(Baseline; 26 weeks (post-intervention))
- Physical function - chair sit-and-reach (hamstring flexibility)(Baseline; 26 weeks (post-intervention))
- Physical function - back scratch (shoulder flexibility)(Baseline; 26 weeks (post-intervention))
- Physical function - 8-foot up-and-go (mobility/agility)(Baseline; 26 weeks (post-intervention))
- Physical function - one-leg standing balance (OLSB)(Baseline; 26 weeks (post-intervention))
- MRI - structural T1-weighted imaging(Baseline; 26 weeks (post-intervention))
- MRI - task fMRI(Baseline; 26 weeks (post-intervention))
- MRI - resting-state fMRI(Baseline; 26 weeks (post-intervention))
- MRI - perfusion(Baseline; 26 weeks (post-intervention))
- Health-related quality of life - SF-12(Baseline; 26 weeks (post-intervention))
- Lung function - forced expiratory manoeuvre (FVC)(Baseline; 26 weeks (post-intervention))
- Lung function - forced expiratory manoeuvre (FEV₁)(Baseline; 26 weeks (post-intervention))
- Lung function - maximum voluntary ventilation (MVV)(Baseline; 26 weeks (post-intervention))
- Ventilatory mechanics - exercise flow-volume loop overlap (ventilatory constraint)(Baseline; 26 weeks (post-intervention))
- Physical activity levels - accelerometry (ActiGraph GT3X+)(Baseline (start of intervention); mid-intervention; 26 weeks (end/post-intervention))