A technology-blended exercise intervention for cognitive risk reduction and brain health in middle-aged and older adults with type 2 diabetes in Singapore: a mixed-methods study

Abstract

Background

Type 2 diabetes mellitus (T2DM) is a major modifiable risk factor for accelerated brain ageing, cognitive decline, and dementia. However, sustainable lifestyle interventions targeting cognitive health in at-risk older adult populations remain limited. This mixed-methods study evaluated the effects of a 12-week technology-blended Intensive Aerobic and Resistance Exercise Program (IAREP) on cognitive risk and related health outcomes among middle-aged and older adults with T2DM in a primary care setting in Singapore.

Methods

Participants were recruited from a community polyclinic and allocated to either the intervention or usual care group. The intervention integrated face-to-face, Zoom-based, and video-recorded home exercise sessions to support accessibility and adherence. Quantitative outcomes included cognitive impairment (CI) risk, physical function, metabolic and inflammatory markers, physical activity, and self-care maintenance. Qualitative focus group discussions (FGDs) explored participant experiences following program completion.

Results

Fifty-three participants completed the study (mean age 66.7 years). Compared with usual care, the intervention group demonstrated significant reductions in predicted risk of CI (F(1,51) = 4.9, p = .031, η²_p = 0.088), improvements in physical function (F(1,51) = 10.6, p = .002, η²_p = 0.172), and higher physical activity levels (F(1,51) = 8.3, p = .006, η²_p = 0.140). Self-care maintenance also improved significantly (F(1,51) = 4.5, p = .040, η²_p = 0.081). Adherence was high (88.9%). Qualitative findings highlighted enhanced motivation, social connectedness, and perceived cognitive and physical well-being.

Conclusions

These findings support technology-blended exercise might be a feasible and scalable strategy for cognitive risk reduction and brain health promotion among middle-aged and older adults with T2DM, with potential translational relevance for dementia prevention in primary care and community settings.

Clinical trial registration number

NCT06401733

Introduction

The global epidemic of diabetes mellitus poses a significant threat to public health, with an estimated 536.6 million people worldwide living with diabetes.¹ Type 2 Diabetes Mellitus (T2DM) is associated with a range of complications, including cognitive decline, cardiovascular disease, physical disability, and sarcopenia, which place a substantial burden on healthcare systems and reduce the quality of life for affected individuals.² The prevalence of cognitive impairment (CI) ranges from 21.8% to 67.5% across various countries and populations among T2DM.³ Evidence showed midlife physical activity reduces late-life dementia and CI.⁴ Exercise has emerged as one of the most effective and cost-efficient non-pharmacological interventions that improve cognitive function, glycemic control, cardiovascular health, and overall well-being in individuals with T2DM.⁵

While exercise is highly beneficial, low compliance rates remain a significant barrier, particularly among middle-aged and older adults with T2DM.⁶ Sustaining regular exercise is often hindered by barriers, including busy schedules, low motivation, physical limitations, social isolation, and racial disparities.⁷ Traditional exercise programs often lack flexibility, personalized guidance, or innovative delivery methods tailored to the unique needs of this population. This limitation affects accessibility and engagement, particularly for older adults who may face mobility or scheduling constraints. Additionally, few programs offer a specific, evidence-based exercise protocol for the T2DM population that combines multiple exercise modalities with guided instruction.

To address these challenges, technology-based interventions have gained traction as flexible, engaging solutions. Virtual fitness platforms (eg, Zoom-based exercise) offer social connection, convenience, and accessibility, allowing participants to exercise at their own pace and schedule.⁸ One study showed that adding home-based tele-exercise improves exercise adherence in individuals with chronic diseases.⁹ Integrating motivational strategies, such as chatbots (eg, Telegram) and gamification, significantly increases user adherence and engagement across domains such as health and fitness.¹⁰ Studies in other countries have demonstrated that technology-based exercise programs can significantly enhance compliance and health outcomes in individuals with T2DM.¹¹ However, the effectiveness of such interventions may vary across cultures and populations, highlighting the need for culturally tailored programs that address local preferences and barriers. Given the unique challenges faced by middle-aged and older adults with T2DM, there is a critical need for tailored exercise programs that are both effective and accessible.

The Intensive Aerobic and Resistance Exercise Program (IAREP) was designed to address this gap, using a blended, technology-supported model for middle-aged and older adults with T2DM. This study aims to examine the effectiveness of the IAREP on cognition, metabolism, inflammation, physical health, and self-care practices, focusing on how its unique design supports adherence to exercise-related behavioral change.

Methods

Design, setting, and participants

The study employed an explanatory mixed-methods design consisting of a quasi-experimental approach and a qualitative process evaluation through FGDs. Following ethical approval from the Domain Specific Review Board (2022/00594), all screened subjects provided informed consent after being fully briefed on the study’s purpose, procedures, and potential risks, and confidentiality was maintained by de-identifying all data. The study was registered in ClinicalTrials.gov (NCT06401733).

Participants were recruited from a polyclinic in western Singapore using convenience sampling, and the 12-week intervention was delivered between May and July 2024 (Figure 1). The eligibility criteria were subjects who were (1) aged 40-85; (2) living in the community; (3) diagnosed with T2DM; (4) literate in English or Mandarin; (5) independent in Activities of Daily Living; and (6) obtained at least a score of 5 in the Short Physical Performance Battery (SPPB) test. Exclusion criteria were: (1) severe cognitive or psychiatric disorders; (2) severe hearing or vision impairments; (3) terminally ill medical conditions, severe cardiovascular, respiratory, or orthopedic conditions; (4) absolute contraindications to aerobic exercise and resistance training programs; (5) pregnant or breastfeeding women; (6) uncomfortable with video recording of intervention sessions.

Figure 1.

CONSORT diagram of study flow. CONSORT flow diagram illustrating participant recruitment, allocation, follow-up, and analysis. A total of 150 individuals were assessed for eligibility. Ninety-two were excluded, including 40 who could not be contacted, 45 who declined participation, and 7 for other reasons. Fifty-eight participants were enrolled in the quasi-experimental study, with 27 allocated to the intervention group and 31 to the control group. During follow-up, 2 participants in the intervention group withdrew because of medical conditions, and 3 participants in the control group were lost to follow-up because they were unable to attend the assessment due to scheduling constraints. The final analyses included 25 participants in the intervention group and 28 participants in the control group.

Participants were selected from a prior cohort of 150 individuals.¹² In view of the majority of our population being working adults, due to their willingness to exercise and availability to the exercise schedule, we’ve adopted the non-randomized quasi-experimental trial. For this 2-arm quasi-experimental trial, a total of 80 participants (40 per group: intervention vs control) were enrolled, adhering to Brown et al.’s¹³ recommendation of a minimum of 30 subjects per parameter in quantitative analyses. Alongside quantitative measures, a qualitative process evaluation was conducted through FGDs with all intervention group participants. FGDs continued until thematic saturation was achieved, allowing for triangulation of quantitative outcomes with participants’ experiential insights.

Intensive Aerobic and Resistance Exercise Program

The IAREP (Figure 2) was a 12-week technology-blended exercise program based on the American College of Sports Medicine and the Singapore Physical Activity Guideline.^14,15 It incorporated FITT-based exercise prescription, Borg Rating of Perceived Exertion (RPE)-guided progression, and blended delivery through face-to-face, Zoom-based, and video-recorded components (Tables S1-S4).

Figure 2.

Overview of the technology-blended intensive aerobic and resistance exercise programme (IAREP). Conceptual framework of the IAREP intervention. The 12-week intervention comprised 36 exercise sessions and was developed based on the American College of Sports Medicine (ACSM) and Singapore physical activity guidelines. The program included 3 integrated components: (1) an exercise prescription based on the FITT (Frequency, Intensity, Time, and Type) principles, consisting of moderate-to-vigorous, low-impact combined aerobic and resistance exercise performed 3 times per week for 45-60 min per session (135-180 min per week); (2) a tailored design with progression guided by rating of perceived exertion (RPE), individual adjustment, and exercise options of varying difficulty; and (3) a blended delivery model combining face-to-face group exercise in the polyclinic, live group exercise via zoom at home, and individual video-recorded exercise sessions at home.

Control group

Participants in the control group received usual care in the polyclinics, including the services of routine checkups, screenings, and medication treatment.

Data collection

Quantitative quasi-experimental trial

Data were collected at baseline and at 3 months post-intervention through cognitive assessments, blood tests, and questionnaires. The primary outcome was cognition, measured using the Vascular Dementia Battery (VDB)¹⁶ and Risk Stratification Scores (RSS).¹² VDB was used in this study to categorize subjects into CI and non-CI groups. CI was defined as failing one or more cognitive domains on formal neuropsychological tests, including executive function (Fontal Assessment Battery), attention (Digit Span, Visual Memory Span, Auditory Detection Test), language (Modified Bostan Naming, Verbal Fluency), verbal memory (Word List Recall, Story Recall), visual memory (Picture Recall, WMS-R Visual Reproduction), visual construction (WMS-R Visual Reproduction, Clock Drawing Test, WAIS-R Block Design), and visuomotor speed (Digit Cancelation Task Symbol, Digit Modalities Task, Maze Task); a domain was considered impaired if the subject failed at least 50% of its tasks.¹⁶ This formal neuropsychological test had previously been validated in Singapore.¹⁶ RSS was derived from an earlier study by the team, is a prediction model developed using logistic regression, with CI status determined by the VDB assessment as the outcome, which screened for CI risk using the Montreal Cognitive Assessment (MoCA, as a screening tool for mild CI, evaluates multiple cognitive domains, including visuospatial/executive function, naming, attention, language, abstraction, delayed recall, and orientation),¹⁷ the SPPB, and diastolic blood pressure.¹² The cutoff score of 0.3 was combined according to the published scoring algorithm to generate an overall RSS, with higher scores indicating a greater predicted risk of CI. In this study, the RSS was used as a composite outcome to estimate participants’ risk of CI rather than as a diagnostic measure of current CI.

The secondary outcomes included metabolic glycemic profile (HbA1c), inflammatory markers (IL-6, CRP, and TNF-α), SPPB, rapid sarcopenia screening (SARC-F), blood pressure, physical activity status (International Physical Activity Questionnaire Short Form, IPAQ-SF), Self-Care of Diabetes Inventory (SCODI), and Self-Rated Abilities for Health Practice scale (SRAHP).

Qualitative process evaluation

Process evaluation was conducted through FGDs, utilizing a semi-structured interview guide. Upon completion of the intervention, all intervention completers were invited to participate in the FGDs. The process evaluation framework developed by Saunders et al.¹⁸ was used to systematically assess program implementation. There was at least 1 facilitator, 1 note-taker, and groups of 4-6 participants for each session. The semi-structured interview questions (Table S5) focused on satisfaction, motivations, adherence challenges, and perceived benefits. Sessions were conducted in either English or Chinese and were audio-recorded for verbatim transcription. Chinese transcripts were translated into English, and the English transcripts were used for coding, analysis, and reporting. Structured exercise observations tracked participation, technique, and adherence, objectively validating feedback. Observations during FGDs captured nonverbal cues of engagement, emotions, and group dynamics, enriching the interpretation of transcripts.¹⁹ Facilitators documented behavioral cues (interaction, participation levels) in field notes, later integrating them with FGD data for nuanced analysis, ensuring a comprehensive understanding of participant perspectives.

Each participant was compensated up to USD 70 for their participation in the pre- and post-intervention assessments and FGD.

Data analysis

Data were managed using SPSS version 29. Descriptive analyses were conducted to explore sociodemographic and clinical data, with medians and interquartile ranges (IQRs) utilized. For statistical analysis, the Wilcoxon signed-rank test was used to assess within-group changes between the pre- and post-intervention phases. In contrast, the Quade nonparametric analysis of covariance (ANCOVA) was used to compare differences between the intervention and control groups, adjusting for each group’s baseline values of the outcome variables. A 2-sided t-test was used, with a p-value threshold of .05 set for statistical significance.

Two researchers transcribed the recording material into text and conducted a cross-check to ensure the completeness and accuracy of the data. Data were uploaded and organized using NVivo 14.0. The FGDs were coded independently by 2 researchers (J.Z. & J.M.) trained in qualitative methods. Codes and themes were compared and refined through discussion within the research team until consensus was reached. Formal inter-coder agreement statistics were not calculated. The discrepancy was resolved by a third researcher (V.X.W), who was the senior researcher on the qualitative study. Thematic analysis²⁰ was employed to analyze the data from FGDs. An inductive approach, grounded in the transtheoretical model,²¹ was initially employed to identify emergent themes, followed by deductive analysis to refine and categorize these themes and subthemes.

Results

Participant characteristics

A total of 53 participants were recruited, with 25 in the intervention group and 28 in the control group. The median age of the participants was 67.0 years, and 49.1% were female. Table 1 provides additional information on participants’ demographics. Of the 25 participants who completed the intervention, 24 agreed to participate in the FGDs, while 1 declined due to personal reasons.

Table 1.

Baseline demographics and clinical data (N = 53).

Characteristics	Intervention n = 25	Control n = 28	p-value
	n (%) or median (IQR)	n (%) or median (IQR)
Age	68.0 (60.0-73.0)	66.0 (60.5-74.0)	.87
Middle-aged adults (40-60 years)	7 (28.0)	7 (25.0)
Older adults (>60 years)	18 (72.0)	21 (75.0)
Gender			.69
Female	13 (52.0)	13 (46.4)
Male	12 (48.0)	15 (53.6)
Ethnic			<.01*
Chinese	23 (92.0)	14 (50.0)
Malay	2 (8.0)	4 (14.3)
Indian	0 (0)	8 (28.6)
Othersa	0 (0)	2 (7.1)
Education			.40
Nil and primary	6 (24.0)	6 (21.4)
Secondary/institute of technical education/pre-university/polytechnic	11 (44.0)	17 (60.7)
University	8 (32.0)	5 (17.9)
Waist-hip ratio	0.9 (0.9-1.0)	1.0 (0.9-1.0)	.19
Normal	6 (24.0)	2 (7.1)
Central obesity	19 (76.0)	26 (92.9)
Body mass index	25.7 (23.9-27.4)	26.6 (22.6-29.2)	.62
Healthy weight (18.5-24.9 kg/m2)	11 (44.0)	10 (35.7)
Overweight (25.0-29.9 kg/m2)	11 (44.0)	15 (53.6)
Obese (30 kg/m2 or higher)	3 (12.0)	3 (10.7)
Comorbidities			.99
0-1	8 (32.0)	9 (32.1)
≥2	17 (68.0)	19 (67.9)
CI status			.59
Non-CI	13 (52.0)	12 (42.9)
CI	12 (48.0)	16 (57.1)
Failed cognitive domainsb
Executive function	2 (8.0)	0 (0)	.22
Attention	0 (0)	0 (0)	1.00
Language	0 (0)	1 (3.6)	.63
Verbal memory	3 (12.0)	4 (14.3)	.44
Visual memory	8 (32.0)	12 (42.9)	.63
Visual construction	1 (4.0)	7 (25.0)	.10
Visuomotor speed	3 (12.0)	8 (28.6)	.29
Risk Stratification Score	−0.2 (−1.2-0.7)	−0.1 (−0.8-2.2)	.38
MoCA score	25.0 (22.5-27.0)	24.5 (21.3-26.0)	.44
HbA1c (%)	7.0 (6.4-7.5)	7.5 (7.0-8.1)	.02*
IL-6 (pg/mL)	0.4 (0.2-0.9)	0.4 (0.3-0.9)	.50
TNF-α (pg/mL)	1.47 (1.2-1.8)	1.46 (1.1-2.0)	.89
CRP (ng/mL)	834.1 (243.6-2474.8)	2008.6 (754.8-5847.3)	.04*
Systolic blood pressure (mmHg)	134.0 (122.0-146.5)	133.5 (124.3-141.8)	.82
Diastolic blood pressure (mmHg)	73.0 (67.5-81.5)	72.0 (64.3-81.0)	.53
SPPB score	11.0 (9.0-12.0)	11.0 (9.0-12.0)	.74
SARC-F score	0.0 (0.0-1.0)	1.0 (0.0-2.0)	.14
SCODI maintenance	89.6 (71.9-91.7)	83.3 (75.0-91.7)	.13
SCODI monitoring	58.8 (44.1-70.6)	55.9 (36.0-75.0)	.62
SCODI management	53.1 (37.5-71.9)	54.3 (34.4-68.8)	.44
SCODI confidence	77.3 (68.2-93.2)	77.3 (63.6-85.8)	.28
SRAHP score	99.0 (73.5-108.0)	93.0 (78.3-101.8)	.34
IPAQ-SF (MET-min/week)c	693.0 (297.0-1288.5)	747.0 (346.5-1406.3)	.62
Low physical activity level	12 (48.0)	11 (39.3)
Moderate physical activity level	13 (52.0)	15 (53.6)
High physical activity level	0 (0)	2 (7.1)

Abbreviations: CRP, C-reactive protein; Hb1Ac, glycated haemoglobin; IL-6, interleukin-6; CI, cognitive impairment; IPAQ-SF, International Physical Activity Questionnaire—Short Form; MET, metabolic equivalent of task-minutes; MoCA, Montreal Cognitive Assessment; SPPB, Short Physical Performance Battery; SARC-F, sarcopenia screening test (Strength, Assistance in walking, Rise from a chair, Climb stairs, Falls); SCODI, Self-Care of Diabetes Inventory; SRAHP, Self-Rated Abilities for Health Practice scale; TNF-α, tumor necrosis factor-alpha.

^aTwo participants represented other ethnicities in the control group; one participant was Filipino, and another was from Myanmar.

^bThe number of participants who failed the respective cognitive domains from the vascular dementia battery.

^cIPAQ-SF physical activity levels were categorized according to the IPAQ scoring protocol into low, moderate, and high physical activity levels.

^* p < .05.

Quantitative results

Cognition (primary outcome)

The VDB showed no statistically significant intervention effects across its 7 cognitive domains (all p > .05). Attention demonstrated the largest but non-significant effect (F(1,51) = 2.8, p = .100, η²_p = 0.052), while other domains showed negligible to small non-significant effects (Table 2). The intervention group demonstrated a statistically significant reduction in the RSS score compared to the control group (F(1,51) = 4.9, p = .031, η²_p = 0.088, medium effect), suggesting that the IAREP intervention may reduce the predicted risk of CI. As RSS is a prediction score derived from MoCA, SPPB, and DBP, the observed reduction may reflect improvements in one or more of these predictors rather than cognitive performance alone, further examination is needed to examine the individual components of the RSS. MoCA scores showed no statistically significant group difference with a negligible effect size (F(1,51) = 0.6, p = .434, η²_p = 0.012).

Table 2.

Pre- and post-test comparisons and clinical outcome differences in intervention and control groups.

Variables	Intervention group, n = 25				Control group, n = 28				Between group Quade nonparametric ANCOVAa
	Pre	Post			Pre	Post
	Median (IQR)	Median (IQR)	W	p	Median (IQR)	Median (IQR)	W	p	F	t	p	η²p
Cognition (primary outcome)
Executive function	3.0 (3.0-3.0)	3.0 (3.0-3.0)	4.0	.564	3.0 (3.0-3.0)	3.0 (3.0-3.0)	0.0	1.000	1.2	1.1	.275	0.023
Attention	3.0 (3.0-3.0)	3.0 (3.0-3.0)	6.0	.655	3.0 (2.0-3.0)	2.5 (2.0-3.0)	3.5	.102	2.8	−1.7	.100	0.052
Language	3.0 (3.0-3.0)	3.0 (3.0-3.0)	5.0	1.000	3.0 (3.0-3.0)	3.0 (3.0-3.0)	5.0	1.000	0.3	−0.5	.612	0.006
Verbal memory	3.0 (2.0-3.0)	3.0 (2.0-3.0)	12.0	.705	2.0 (2.0-3.0)	2.0 (2.0-3.0)	32.5	.564	0.6	−0.8	.432	0.012
Visual memory	2.0 (1.0-3.0)	2.0 (1.5-3.0)	31.5	.248	2.0 (1.0-3.0)	2.0 (1.0-3.0)	54.5	.499	0.6	−0.8	.430	0.012
Visuo-construction	2.0 (2.0-2.0)	2.0 (2.0-2.0)	15.0	.317	2.0 (1.3-2.0)	2.0 (1.0-2.0)	9.0	.739	0.4	−0.6	.544	0.008
Visuomotor speed	3.0 (2.0-3.0)	3.0 (2.0-3.0)	16.0	.705	2.0 (1.0-3.0)	2.5 (1.0-3.0)	18.0	1.000	0.5	−0.7	.472	0.010
RSS	−0.2 (−1.2-0.7)	−0.8 (−1.8-0.1)	168.5	.872	−0.1 (−0.1-2.2)	−0.0 (−0.9-1.7)	268.0	.139	4.9	2.2	.031*	0.088
MoCA	25.0 (22.5-27.0)	25.0 (23.0-27.0)	68.5	.455	24.5 (21.3-26.0)	24.0 (21.5-26.8)	103.0	.442	0.6	−0.8	.434	0.012
Physical function
SPPB	11.0 (9.0-12.0)	11.0 (11.0-12.0)	83.0	.007*	11.0 (9.0-12.0)	10.0 (8.1-12.0)	34.0	.073	10.6	−3.3	.002*	0.172
SARC-F	0.0 (0.0-1.0)	0.0 (0.0-1.0)	10.5	.272	1.0 (0.0-2.0)	1.0 (0.0-1.8)	50.0	.744	3.2	1.8	.079	0.059
Vascular health
SBP	134.0 (122.0-146.5)	131.0 (122.0-141.0)	106.5	.131	133.5 (124.3-141.8)	134.5 (122.8-146.0)	180.0	.909	1.5	1.2	.226	0.029
DBP	73.0 (67.5-81.5)	78.0 (70.5-87.0)	173.5	.767	72.0 (64.3-81.0)	73.5 (65.8-80.8)	114.5	.196	3.4	−1.8	.072	0.063
Metabolic and inflammatory health
HbA1c (%)	7.0 (6.4-7.5)	6.9 (6.2-7.6)	168.5	.871	7.5 (7.0-8.1)	7.3 (7.1-8.0)	225.0	.616	0.8	0.9	.378	0.015
IL-6 (pg/mL)	0.4 (0.2-0.9)	0.9 (0.4-1.3)	165.0	.946	0.4 (0.3-0.9)	1.0 (0.7-1.6)	263.0	.172	1.4	1.2	.236	0.027
CRP (ng/mL)	834.1 (243.6-2474.8)	1011.8 (187.0-2790.8)	164.0	.968	2008.6 (754.9-5847.3)	1161.7 (681.5-3329.4)	144.0	.179	0.0	−0.1	.898	0.000
TNF-α (pg/mL)	1.5 (1.2-1.8)	1.4 (1.1-2.0)	115.5	.206	1.5 (1.1-2.0)	1.4 (1.2-1.9)	192.5	.811	0.2	0.4	.666	0.004
Physical activity level
IPAQ-SF (MET-min/week)	693.0 (297.0-1288.5)	1182.0 (791.3-1727.3)	269.0	.004*	747.0 (346.5-1406.3)	594.0 (222.8-1386.0)	100.0	.093	8.3	−2.9	.006*	0.140
Self-care and health practice behaviour
SCODI maintenance	89.6 (71.9-91.7)	87.5 (82.3-91.7)	163.5	.094	83.3 (75.0-91.7)	82.3 (71.4-89.6)	155.0	.602	4.5	−2.1	.040*	0.081
SCODI monitoring	58.8 (44.1-70.6)	47.1 (35.3-63.2)	95.0	.069	55.9 (36.0-75.0)	50.0 (33.1-63.2)	173.0	.494	0.6	0.8	.457	0.012
SCODI management	53.1 (37.5-71.9)	53.1 (35.9-75.0)	136.5	.745	54.3 (34.4-68.8)	48.4 (34.4-78.1)	190.5	.703	0.1	−0.3	.760	0.002
SCODI confidence	77.3 (68.2-93.2)	79.6 (64.8-94.3)	190.0	.459	77.3 (63.6-85.8)	69.3 (54.6-79.6)	156.0	.284	1.7	−1.3	.197	0.032
SRAHP	99.0 (73.5-108.0)	96.0 (82.5-105.5)	131.5	.843	93.0 (78.3-101.8)	86.5 (74.5-104.8)	158.5	.463	0.5	−0.7	.495	0.010

Abbreviations: ANCOVA, analysis of covariance; CRP, C-reactive protein; DBP, diastolic blood pressure; HbA1c, glycated haemoglobin; IL-6, interleukin-6; IPAQ-SF, International Physical Activity Questionnaire—Short Form; MET, metabolic equivalent of task; MoCA, Montreal Cognitive Assessment; RSS, Risk Stratification Score; SARC-F, sarcopenia screening test (Strength, Assistance in walking, Rise from a chair, Climb stairs, Falls); SBP, systolic blood pressure; SCODI, Self-Care of Diabetes Inventory; SPPB, Short Physical Performance Battery; SRAHP, Self-Rated Abilities for Health Practice scale; TNF-α, tumor necrosis factor-alpha.

^aGroup differences (control vs intervention) were analyzed using Quade’s rank ANCOVA; the analysis adjusted for the respective baseline values of the outcome variables.

^* p < .05.

Physical function

The SPPB score demonstrated a statistically significant improvement in the intervention group compared to the control group, with a large effect size (F(1,51) = 10.6, p = .002, η²_p = 0.172). Within-group analysis confirmed significant improvement in the intervention group (W = 83.0, p = .007). For sarcopenia risk, SARC-F scores showed a marginally significant small-to-medium reduction (F(1,51) = 3.2, p = .079, η²_p = 0.059).

Vascular health

The intervention group showed a non-significant decrease in systolic blood pressure from 134.0 mmHg (IQR 122.0-146.5) to 131.0 mmHg (IQR 122.0-141.0) (W = 106.5, p = .131), while the control group demonstrated a marginal increase from 133.5 mmHg (IQR 124.3-141.8) to 134.5 mmHg (IQR 122.8-146.0; W = 180.0, p = .909). The diastolic blood pressure patterns differed, with the intervention group increasing from 73.0 mmHg (IQR 67.5-81.5) to 78.0 mmHg (IQR 70.5-87.0) (W = 173.5, p = .767), compared to a negligible change in controls (72.0 mmHg [IQR 64.3-81.0] to 73.5 mmHg [IQR 65.8-80.8]; W = 114.5, p = .196).

Metabolic and inflammatory health

Metabolic control showed no significant intervention effects. HbA1c levels demonstrated no statistically significant difference between groups (F(1,51) = 0.8, p = .378, η²_p = 0.015), and within-group analyses showed no significant changes over time in either group. Inflammatory markers (IL-6, CRP, TNF-α) also showed no significant differences in within- or between-group comparisons.

Physical activity level

Total physical activity measured by IPAQ-SF (MET-min/week) demonstrated a significant between-group difference (F(1,51) = 8.3, p = .006, η²_p = 0.140), indicating a large effect size. Within-group analysis showed a significant increase in the intervention group (W = 269.0, p = .004), whereas no significant change was observed in the control group (W = 100.0, p = .093).

Self-care and health practice behavior

Within-group analyses showed no significant changes across SCODI domains in either the intervention or control groups (all p > .05). Between-group comparisons revealed a significant difference in SCODI self-care maintenance (F(1,51) = 4.5, p = .040, η²_p = 0.081), indicating a moderate effect size. This effect reflects a relative preservation of maintenance behaviors in the intervention group, whereas a greater decline was observed in the control group over time. No significant between-group differences were identified for SCODI self-care monitoring (F(1,51) = 0.6, p = .457, η²_p = 0.012), self-care management (F(1,51) = 0.1, p = .760, η²_p = 0.002), self-care confidence (F(1,51) = 1.7, p = .197, η²_p = 0.032), or SRAHP (F(1,51) = 0.5, p = .495, η²_p = 0.010), all demonstrating small effect sizes.

Qualitative themes

Three themes and 11 sub-themes emerged from the thematic analysis of the participants’ perspectives of the IAREP. The 3 themes are: (1) Journey of transformation and adaptation; (2) Power of connection; (3) Harmony and commitment in holistic wellness and lifelong exercise.

Journey of transformation and adaptation

This theme consists of 4 subthemes: (1) Establishing discipline in exercise habits through program commitment; (2) Building resilience while navigating challenges and uncertainties; (3) Cultivating confidence through guidance and education; and (4) Sustaining exercise through personalized and flexible routines. Through IAREP’s technology-blended approach (in-person, Zoom-based, video-recorded), participants experienced changes in exercise behavior as a transformative journey. While structured support, professional guidance, and personalized routines facilitated sustained engagement, participants also encountered practical challenges, including interruptions from video advertisements, occasional feelings of isolation during home-based exercise, time constraints, technology-related difficulties, and episodes of physical discomfort. These experiences highlighted exercise as an ongoing process of adaptation in which both facilitators and barriers shaped long-term engagement.

Discipline emerged as the foundation of participants’ fitness journeys, serving as a structured commitment that anchored their engagement. Participants viewed discipline as both a motivator and a challenge, reflecting their efforts to sustain consistency in exercise habits.

Joining this program is a commitment. It doesn’t mean you can just not go; there’s a certain commitment there, and with that commitment, being people like me, retired routine, forcing you to have exercise activities there. (Participant A1)

Participants also described a range of challenges during the intervention. Some experienced frustration with repeated video advertisements that interrupted exercise sessions, while others reported occasional feelings of isolation during home-based exercise, technology-related barriers, competing time demands, or temporary physical discomfort. Despite these challenges, many participants described adapting their strategies to remain engaged.

The advertisement in the video was disruptive and frustrating, as it repeatedly interrupted the flow, requiring me to wait 3-5 seconds before continuing. But I realised these small obstacles made me more adaptable. Instead of resisting the interruptions, I used them as moments to catch my breath, refocus, or replay missed steps. (Participant D3)

Clear instructions and professional advice played a crucial role in helping participants avoid mistakes and build confidence to establish a habit. Guidance provided structure and reassurance, especially for beginners.

For beginners like me, this structured approach is highly beneficial because it provides an instructor to correct our mistakes during face-to-face exercises and to monitor our movements to ensure safety and establish a consistent exercise habit. (Participant D2)

Tailoring routines to individual needs made exercise more sustainable and relevant for participants, thereby enabling them to address specific challenges and achieve specific goals.

We use computers a lot, which causes pain in my neck and shoulders. After learning many movements from the trainer, I began exercising my muscles at any time using an elastic band. It’s very useful and effective. (Participant B5)

Power of connection

The theme of Power of Connection consists of 3 subthemes: (1) Finding accountability through the supportive network and community group dynamic, (2) Active involvement fostering empowerment through participation, and (3) Overcoming isolation by building social connection. Participants described how group exercise transformed physical activity into a shared experience with meaning and significance. Collective struggles and successes turned workouts from solitary tasks into communal experiences, where peer energy created natural accountability and motivation. Beyond camaraderie, these connections alleviated isolation by fostering a sense of belonging, making even challenging routines feel achievable through laughter and support. This social framework sustained commitment and amplified joy in progress.

Supportive networks with peers, family, and friends created an environment of encouragement and belonging. These connections amplified the positive aspects of exercise, fostering a sense of community.

When there’s a family gathering, I’ll talk to my brother-in-law regarding the exercises… I told him that he was very monotonous and suggested adding a variety of exercises from IAREP, which he agreed to. Hence, I sent him our exercise videos, and he showed interest. We have additional topics to discuss, and I shared with him the type of exercise we are doing on Saturday. (Participant D2)

Feeling valued and included in group activities enhanced participants’ sense of belonging and engagement. One participant highlighted that empowerment stemmed from opportunities to contribute and take ownership of the program.

If you involve all the people in designing your program, it is the best. It gives you a sense of participation. If not, you don’t feel the happiness or pleasure of participating. (Participants B5)

Moreover, participants consistently highlighted the challenges of isolation experienced during virtual or solitary exercise settings, which negatively impacted their motivation and sense of accountability. The absence of real-time social interaction diminished their engagement and enjoyment, shifting their preference toward outdoor face-to-face exercise, interactive virtual exercise, or having family accompany them during exercise to alleviate loneliness.

I enjoy it because we come together and do the exercises, and it feels like we have friends. If you do it alone, it’s very boring. If you have friends and you do it together, you feel happier in a group. (Participant B2)

Harmony and commitment in holistic wellness and lifelong exercise

This theme consists of 4 subthemes: (1) Finding satisfaction and physical benefits in exercise; (2) Understanding the long-term benefits of exercise on health; (3) Enhancing mental health and emotional stability through exercise; and (4) Setting and achieving goals to maintain momentum. Participants transformed exercise from a chore to a joyful movement, observing improved flexibility and mobility that enhanced their daily functioning (eg, stair climbing). These physical gains, coupled with broader health benefits (such as improved sleep and better glycemic control), reinforced the commitment. Exercise also boosts mental health by stabilizing mood and reducing stress. Goal achievement fostered motivation, while tangible outcomes, such as blood pressure regulation, sustained engagement. Notably, IAREP enhanced cognitive functions, and participants reported sharper focus (eg, during chess), longer attention spans, and improved facial recognition.

Participants found satisfaction and physical benefits in exercise, transforming it from a chore into a source of joy in movement. This shift in perspective enhanced their engagement and motivation.

I think my hands and feet were more flexible after (IAREP) exercising, and I feel better when I walk up and step down the stairs. (Participant E2)

Understanding the cumulative impact of exercise on health and well-being motivated participants to sustain their engagement. The long-term benefits extended beyond physical fitness to include improved sleep, disease management, and overall quality of life.

It will help people with diabetes in the long term; it will help me control my diet through exercise. (Participant A5)

Participants recognized how physical activity enhanced mental health, emotional stability, and overall health. This integration of mind and body created a sense of balance and harmony by enhancing mental health and emotional stability through exercise.

It improves my memory. I know I must improve in recognising people. When we went out to meet some of my old friends and colleagues, I was fortunate to recognise them: “Hello, Mr XX.” “Yeah, I remember you after I see you.” Even though I didn’t see them for a long time. I think the physical exercise (IAREP) effect is holistic on both physical and mental health. I think that is very good and useful for ageing people like us. (Participant A3)

Lastly, having explored the cultivation of endurance through goal setting and personal motivation, the focus shifts to the practical integration of exercise into daily life. For fitness to become a lifelong commitment, it must seamlessly blend with existing routines and be perceived as enjoyable, rather than a chore.

We need ways to track progress, such as self-assessment, but it’s difficult to know whether I’m truly improving mentally or physically. Seeing positive results after exercise motivates me to keep going. Small wins prove my effort matters, and that keeps me committed. (Participant C1)

Integration of quantitative results and qualitative themes

This mixed-methods study integrated quantitative and qualitative findings to explain how participants’ experiences contextualized the observed intervention effects (Figure 3). Participants demonstrated high adherence to the IAREP, with a median of 88.9% (IQR: 76.4%-95.8%), attending a median of 10 sessions (IQR: 8-11) out of the 12 planned face-to-face sessions. For the Zoom-based exercise component, participants attended a median of 12 sessions (IQR: 10-12), reflecting high engagement with the virtual live sessions. Additionally, participants self-reportedly performed the video-recorded exercise sessions a median of 11 times (IQR: 9.5-12), indicating consistent participation in the self-guided component of the program. These findings suggest that the intervention was delivered as planned. The qualitative findings suggest that this high adherence was facilitated by structured program commitment, professional guidance, flexible exercise delivery, increased confidence, and social support, providing context for the observed improvements in physical function, physical activity, and self-care maintenance.

Figure 3.

Mixed-methods integration of intervention outcomes. Conceptual diagram illustrating the integration of quantitative and qualitative findings from the intensive aerobic and resistance exercise programme (IAREP) intervention. The left panel summarizes the quantitative findings, including reduced predicted risk of cognitive impairment (RSS, Risk Stratification Score), improved physical function (SPPB, Short Physical Performance Battery), increased physical activity (IPAQ-SF, International Physical Activity Questionnaire—Short Form), improved self-care maintenance (SCODI, Self-Care of Diabetes Inventory), high program adherence, and favorable trends in metabolic and inflammatory markers. The right panel summarizes qualitative findings from the process evaluation, including improved mental well-being, enhanced physical confidence, increased health awareness, strengthened social support and motivation, and greater commitment to sustained behavior change. The Central panel integrates these findings, indicating that the technology-blended IAREP improved physical function and supported sustained self-management. Qualitative findings suggest that increased confidence, motivation, social support, and program commitment contributed to high adherence and sustained exercise participation. Participants also perceived cognitive benefits alongside a lower predicted risk of cognitive impairment, although objective cognitive performance measures (VDB, Vascular Dementia Battery; or MoCA, Montreal Cognitive Assessment) remained unchanged.

Although participants also described perceived improvements in memory, attention, and facial recognition, these subjective experiences were accompanied by a lower predicted risk of CI, as reflected by the significant reduction in RSS. However, no significant improvements were observed in the objective cognitive performance measures (VDB cognitive domains and MoCA). Together, these findings suggest that the intervention may have favorably influenced perceived cognitive functioning and CI risk, although measurable improvements in objective cognitive performance were not detected during the study period.

Discussion

The findings of this study suggest potential benefits of the IAREP in cognition, metabolism, physical function, and promoting exercise adherence among middle-aged and older adults with T2DM. Structured exercise interventions in IAREP offered a promising, transformative strategy for changing exercise behavior.

The study demonstrated that the IAREP reduces CI risk by lowering RSS. The significant reduction in RSS, despite the absence of significant changes in the VDB cognitive domains, highlights the different constructs measured by these outcomes. RSS is a prediction score that estimates the risk of CI, whereas the VDB directly assesses domain-specific cognitive performance. Consequently, the reduction in RSS suggests a lower predicted risk of CI rather than a direct improvement in cognitive performance. This discrepancy may reflect the multidimensional nature of RSS. Improvements in physical function may have contributed to the observed reduction in RSS, whereas no significant changes were detected in the VDB cognitive domains. These findings suggest that the intervention may have favorably influenced CI risk before producing measurable improvements in domain-specific cognitive performance.

Through FGDs, participants described perceived improvements in focus, concentration, facial recognition skills, and processing speed, which they attributed to enhanced hand-eye and lower-limb coordination following IAREP. Consistent with our study results, the combined exercise improved attention and concentration in the T2DM population and enhanced executive and memory domains.²² Structured exercise induces volumetric increases in frontal and parietal regions of the attentional network, accompanied by improvements in attentional performance among older adults.²³ Indeed, concurrent aerobic and resistance exercise improved composite cognitive scores, particularly processing speed, episodic memory, and sustained attention, in older adults with T2DM.²⁴ Although participants described perceived improvements in memory, attention, and facial recognition, these subjective experiences were not reflected in the objective cognitive measures, as neither the VDB cognitive domains nor MoCA demonstrated significant intervention effects. These findings suggest that the intervention may have enhanced participants’ perceptions of cognitive functioning without producing measurable changes in objective cognitive performance over the study period. Emerging evidence suggests that certain antidiabetic therapies, particularly metformin and sodium-glucose cotransporter-2 (SGLT2) inhibitors, may confer additional benefits for cognitive health and dementia risk beyond glycemic control in older adults with T2DM.^25–30 Although medication use was not evaluated in the present study, future multimodal interventions should consider the potential synergistic effects of optimized pharmacological therapy and structured exercise on cognitive health.

Regular physical activity is a cornerstone of T2DM management, as it enhances insulin sensitivity, promotes weight management, and stimulates glucose uptake by muscle cells, thereby lowering blood glucose levels.³¹ These findings are consistent with our study results, which revealed clinically meaningful directional changes in SPPB and SARC-F. The quantitative results were congruent with the FGDs’ findings that IAREP helped participants improve lower limb strength and balance. The SPPB scores increased, and the intervention group showed non-significant but a trend toward lower SARC-F scores, indicating potential improvement in physical performance and functional mobility. In alignment with our data, exercise improves balance in T2DM, particularly in dynamic balance.³² Sarcopenia involves dysregulated pathways and mitochondrial dysfunction, causing muscle loss, weakness, and frailty, which heighten fall risk and disability.³³ Increased physical activity stimulates mitochondrial function, suppresses myostatin to mitigate muscle atrophy,³⁴ and improves AMPK activity,³⁵ thereby enhancing energy balance and physical function, which may reduce fall risk. Participants perceived better balance and greater leg strength during stair climbing when wearing socks or pants. One study found that attention inhibition was associated with static balance in older women, whereas it was associated with dynamic balance in older men.³⁶

The intervention group demonstrated a lower trend of HbA1c levels than the control group, although this difference was not statistically significant. This lack of significance may be attributable to the study’s limited sample size. Evidence showed that each 1% increase in HbA1c was associated with a significantly higher risk of CI.³⁷ Studies have shown that 30 minutes of moderate-to-vigorous exercise per week results in dose-dependent reductions in HbA1c, with maximal efficacy at 100 minutes.³⁸ The observed trend toward lower HbA1c in the exercise intervention group suggests that IAREP potentially improved glycemic control, reinforcing the role of physical activity as a non-pharmacological intervention in T2DM management.³⁹ A reduced HbA1c level suggests enhanced insulin sensitivity.³¹ T2DM contributes to cognitive decline through mechanisms involving inflammation, oxidative stress, and brain insulin resistance, which are driven by mediators such as TNF-α, IL-6, reactive oxygen species, and ceramides.⁴⁰ However, our study did not show significant differences in IL-6, which may be due to the small sample size and might require longer intervention durations. These pathological processes lead to mitochondrial dysfunction, impaired neuronal growth, and reduced glucose utilization in the brain, ultimately resulting in cognitive deficits.⁴¹ Exercise mitigates these effects by enhancing brain vascularization, reducing inflammation and oxidative stress, clearing Aβ via LRP-1 upregulation, and promoting neurogenesis (Figure S1).^42,43 Collectively, these adaptations help mitigate cognitive decline and improve learning and cognitive functions in T2DM patients.

Moreover, improved physical activity and adherence created a positive feedback loop, enhancing physical performance, behavioral change, and social connection. One study indicated that social activities in midlife predict better cognitive function across mid- and later-life across all domains.⁴⁴ Through FGDs, participants reported that the exercise program reinforced their healthy lifestyle behaviors, particularly regarding improved dietary habits and diabetes self-management. Consistent with the quantitative results of improving the SCODI maintenance domain score.

Implications

Clinically, structured exercise should be considered a key preventive strategy, with prescribing tailored regimens to address diabetes-related complications. The blended modality of face-to-face, Zoom-based, and video-recorded sessions can be adapted for broader community health initiatives. For example, community partners and health organizations could offer similar programs to promote physical activity among middle-aged and older adults, particularly those with T2DM and its complications.⁴⁵ By incorporating social support networks and peer mentoring, these programs can enhance motivation and adherence, making exercise more accessible and enjoyable for middle-aged and older adults.⁴⁶ Additionally, the program’s emphasis on personalized and flexible routines can be tailored to address the specific needs of individuals with varying levels of physical ability, ensuring inclusivity and sustainability.

Future research could investigate the long-term effects of programs like IAREP on cognitive, metabolic, inflammatory, and physical function outcomes in individuals with T2DM. Further research could delve deeper into the mechanisms underlying the IAREP, including specific components of the program (eg, social support, personalized routines) that contribute to sustained behavior change and improved health outcomes. This would provide a more nuanced understanding of the factors that drive exercise adherence and long-term success. The success of the blended mode of IAREP with technology suggests that technology-enhanced interventions (eg, mobile apps and wearable devices) could be further explored to enhance engagement and adherence.

The blended modality of face-to-face, Zoom-based, and video-recorded sessions can be adapted for broader community health initiatives. For example, community partners and health organizations could offer similar programs to promote physical activity. By incorporating social support networks and peer mentoring, these programs can enhance motivation and adherence, making exercise more accessible and enjoyable for middle-aged and older adults. Additionally, the program’s emphasis on personalized and flexible routines can be tailored to address the specific needs of individuals with varying levels of physical ability, ensuring inclusivity and sustainability. However, the relatively small sample size from 1 polyclinic may limit the generalizability of the findings, suggesting the need for future studies with larger cohorts to strengthen the conclusions. Additionally, this study highlights the necessity for longitudinal studies to assess sustained impacts. Lastly, physical activity level and other behaviors were evaluated using self-reported measures, which may introduce bias; therefore, incorporating objective measures, such as wearable devices, would enhance the reliability of future findings.

Study limitations

This study has several limitations. The quasi-experimental design was adopted to maximize feasibility in a real-world primary care setting, where recruitment challenges and participant availability limited the practicality of randomization. Although baseline comparability between groups was assessed and statistical adjustment was applied where appropriate, the possibility of residual selection bias cannot be fully excluded. Therefore, the findings should be interpreted with caution, as unmeasured differences between groups may have contributed to the observed effects and limit the ability to draw definitive causal conclusions. The relatively small sample size from a single polyclinic may limit generalizability, and future studies involving larger and more diverse populations are warranted. Exercise participation and related behaviors were assessed using self-reported measures, which may be subject to reporting bias; incorporating objective monitoring tools such as wearable devices in future studies could improve measurement accuracy. Moreover, the qualitative findings may primarily reflect the experiences of participants who completed the intervention and may not fully capture the perspectives of those who withdrew or did not complete the intervention.

Conclusion

In conclusion, this study demonstrates that a technology-blended IAREP is feasible in a real-world primary care setting and is associated with improvements in cognitive status and physical function among adults with T2DM, alongside enhanced self-care maintenance and increased physical activity and exercise participation. The findings highlight the potential of flexible, personalized delivery models to support engagement and diabetes self-management. Further research using larger controlled designs is needed to confirm long-term outcomes and explore underlying mechanisms linking exercise with cognitive and metabolic health.

Supplementary material

Supplementary material is available at The Journals of Gerontology, Series A: Biological Sciences and Medical Sciences online.

Funding

The work was supported by the Japan Society for the Promotion of Science and the National University of Singapore (JSPS-NUS) Joint Research Grant (grant number: A-8000227-01-00). The funders had no role in study design, data collection, data analysis, data interpretation, or writing of the report.

Conflicts of interest

None declared.

Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Author contributions

Jinghua Zhang (Conceptualization [equal], Data curation [lead], Formal analysis [lead], Investigation [equal], Methodology [equal], Project administration [lead], Visualization [equal], Writing—original draft [lead], Writing—review & editing [lead]), Wilson Wai San Tam (Conceptualization [equal], Data curation [equal], Methodology [equal], Supervision [equal], Visualization [equal], Writing—review & editing [equal]), Jinhua Lu (Data curation [equal], Investigation [equal], Writing—review & editing [equal]), Junjie Chen (Data curation [equal], Writing—review & editing [equal]), Jed Montayre (Methodology [equal], Writing—review & editing [equal]), Joji Kusuyama (Writing—review & editing [equal]), Yanhong Dong (Investigation [equal], Writing—review & editing [equal]), Xin Yi Yap (Project administration [equal], Writing—review & editing [equal]), Wentao Zhou (Investigation [equal], Writing—review & editing [equal]), Na Wang (Writing—review & editing [equal]), Hui Nan Yeo (Writing—review & editing [equal]), Frena Jia Sy Lee (Writing—review & editing [equal]), and Vivien Xi Wu (Conceptualization [equal], Data curation [equal], Funding acquisition [lead], Investigation [equal], Methodology [equal], Project administration [equal], Supervision [lead], Visualization [equal], Writing—review & editing [equal])