Effects of Resistance and Dual-Task Training on Physical, Oculomotor, and Executive Functions in Older Adults With MCI

Official title

Study Protocol: Effects of Combined Resistance Training and Dual-Task Interventions on Physical, Oculomotor, and Executive Functions in Older Adults With Mild Cognitive Impairment. A Randomized Controlled Trial

Overview

The goal of this clinical trial is to determine the effect of a combined therapeutic intervention program with anaerobic exercises (resistance exercises) and dual tasks on the physical, oculomotor, and executive functions of older adults with mild cognitive impairment. The main questions it aims to answer are: • How effective will a therapeutic intervention program combining resistance exercises with dual tasks be in improving the physical, oculomotor, and executive functions of older adults with mild cognitive impairment living in the community? Researchers will compare the effectiveness of a resistance exercise training program combined with dual tasks versus a resistance-only exercise training program to see if it improves the physical, oculomotor, and executive functions of older adults with mild cognitive impairment Participants Will: * Receive resistance exercises, resistance exercises combined with dual tasks. or the standard health care. The intervention programs will consist of 3 weekly sessions over 8 weeks. * Before the start and after the completion of the programs, they will be evaluated using a battery of tests. This includes sociodemographic and general health background, physical fitness tests, as well as assessments of executive functions and oculomotor Saccadic movements and anti-saccadic error. * be required to sign a consent form.

Detailed description

A randomized clinical trial will be conducted with two experimental groups and one control group. The target population will be older adults with mild cognitive impairment living in the communities of Arica (Chile) and Valencia (Spain). All participants must score between 10 and 25 points on the Montreal Cognitive Assessment (MoCA).

The sample size was calculated using statistical software, based on mean differences reported in prior studies on training and dual tasks in older adults. A minimum of 11 participants per group was established, adjusted for a 20% dropout rate, a significance level of 0.01, and a statistical power of 0.9.

In each city, 33 participants (men and women in a 1:1 ratio) will be recruited. Random distribution by gender will assign participants to three groups:

EGR: Resistance exercises only.

EGRD: Resistance exercises combined with dual tasks (cognitive tasks).

CG: Control group, receiving standard health care during the study and, upon completion, the best-evaluated therapeutic intervention.

Procedure The study will last 12 weeks: two weeks for baseline measurements (pre-test), eight weeks for training protocols, and two weeks for final measurements (post-test). Evaluations will include sociodemographic and health data, functional physical condition tests, executive function assessments, and saccadic and anti-saccadic eye movement measures.

Interventions will be conducted at the physiotherapy faculties of the participating universities, supervised by experienced professionals blinded to group allocation. Participants will be asked not to engage in physical exercise outside the study protocols during evaluation weeks.

Hypotheses

Primary: The combined intervention of resistance exercises and dual tasks is more effective than isolated resistance training in improving physical, executive, and oculomotor functions in older adults with mild cognitive impairment.

Secondary: The combined intervention produces greater improvements in executive function tasks (Stroop Test, Corsi Block-Tapping Test, Trail Making Test) compared to resistance training alone.

Intervention Program

The intervention will last eight weeks, with three weekly sessions (20-24 sessions total). Each resistance training session will last one hour, divided into:

Warm-up: Joint mobility and basic movements; Resistance training: Exercises with external load; Cool-down: Breathing exercises and stretching.

Exercises will target flexor and extensor groups of the elbow and knee, including bilateral leg press, unilateral knee extensions, and bilateral elbow flexion/extension. Three sets of eight repetitions will be performed for each muscle group. Training intensity will begin at 60% of one-repetition maximum (1RM) and progress to 80% by week 7, adjusted every two weeks based on new strength evaluations and perceived exertion.

The combined group (EGRD) will follow the same physical protocol, incorporating memory and arithmetic tasks during exercise execution.

Assessment Instruments

Functional physical condition: Timed Up and Go Test (TUG), Short Physical Performance Battery (SPPB), and grip strength measured with a hydraulic dynamometer.

Executive functions: Inhibitory control: Stroop Test, with three conditions (word, color, word-color); Working memory: Corsi Block-Tapping Test (CBTT), assessing visuo-spatial memory sequences; Cognitive flexibility: Trail Making Test (TMT-A and TMT-B), evaluating speed, attention, and alternation.

Oculomotor function: Electrooculography (EOG) will record saccadic and anti-saccadic movements using surface electrodes and controlled visual stimuli.

Statistical Analysis Population data will be presented as means for continuous variables and prevalence for categorical variables, with 95% confidence intervals. Inferential analyses will consider normality and homoscedasticity to determine parametric or non-parametric tests. A blinded researcher will conduct all analyses using IBM SPSS version 27.

Interventions

• Procedure Anaerobic therapeutic exercises (resistance exercise)
  The intervention period will last 8 weeks, with 3 sessions per week. Each resistance training session will last one hour and will consist of three parts: the first part will include joint mobility and basic preparatory movements; the second part will involve the resistance training itself (with added weight); and finally, the third part will feature breathing exercises and stretches as a cool-down. Weighted exercises will focus on the elbow flexor/extensor groups and the knee flexor/extensor gro
• Combination product Anaerobic therapeutic exercises (resistance exercise) plus Dual Task
  The anaerobic (resistance) exercise training group combined with dual tasks will follow the same protocol as the previously described anaerobic therapeutic exercise training and will additionally incorporate memory and arithmetic tasks concurrently during the exercises. The intervention period will also last 8 weeks, with 3 sessions per week, and each training session will last one hour (Pantoja-Cardoso et al. 2023).

Primary outcome measures

• Physical-functional condition - Risk of falls [Time frame: Baseline, and immediately post-intervention (week 11),]
• Executive function - Inhibitory control [Time frame: Baseline, and immediately post-intervention (week 11-12)]
• Oculomotor Function- Saccadic and anti-saccadic oculomotor movement [Time frame: Baseline, and immediately post-intervention (week 11)]
• Physical - functional condition - Physical function [Time frame: Baseline, and immediately post-intervention (week 11)]
• Physical - functional condition - Grip Strength [Time frame: Baseline, and immediately post-intervention (week 11)]
• Executive Function - Working Memory [Time frame: Baseline, and immediately post-intervention (week 11-12)]
• Executive Function - Cognitive Flexibility [Time frame: Baseline, and immediately post-intervention (week 11-12)]

Secondary outcome measures (5)

• Sociodemographic variable - Age [Time frame: Baseline]
• Sociodemographic variable - Sex [Time frame: Baseline]
• Sociodemographic variables-Educational Level [Time frame: Baseline]
• Health indicators- Comorbidities [Time frame: Baseline]
• Anthropometric variable- Body Mass Index (BMI) [Time frame: Baseline]

Eligibility criteria

Inclusion criteria

• Men and women aged 60 years or older
• Score between 10 and 25 points on the Montreal Cognitive Assessment (MoCA) scale
• Provide informed consent

Exclusion criteria

• Visual or auditory disability that impedes communication
• Previous diagnosis of dementia
• Wheelchair use
• Epilepsy
• Progressive or terminal illness
• Depression
• History of alcoholism
• Musculoskeletal or cardiovascular contraindications for strength exercises
• Color blindness
• Dyslexia
• Severe mental or cognitive problems supported by medical reports

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Chile · 1 center

• Arica- Chile y Valencia -España — Arica

Spain · 1 center

• Valencia-Spain — Valencia

Publications

• Voos MC, Custodio EB, Malaquias J Jr. Relationship of executive function and educational status with functional balance in older adults. J Geriatr Phys Ther. 2011 Jan-Mar;34(1):11-8. doi: 10.1097/JPT.0b013e3181ff2452. PMID 21937887
• Vandierendonck A. Working memory benchmarks-A missed opportunity: Comment on Oberauer et al. (2018). Psychol Bull. 2018 Sep;144(9):963-971. doi: 10.1037/bul0000159. PMID 30148381
• Heath M, Weiler J, Gregory MA, Gill DP, Petrella RJ. A Six-Month Cognitive-Motor and Aerobic Exercise Program Improves Executive Function in Persons with an Objective Cognitive Impairment: A Pilot Investigation Using the Antisaccade Task. J Alzheimers Dis. 2016 Oct 4;54(3):923-931. doi: 10.3233/JAD-160288. PMID 27567829
• Glisky EL, Alexander GE, Hou M, Kawa K, Woolverton CB, Zigman EK, Nguyen LA, Haws K, Figueredo AJ, Ryan L. Differences between young and older adults in unity and diversity of executive functions. Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2021 Nov;28(6):829-854. doi: 10.1080/13825585.2020.1830936. Epub 2020 Oct 8. PMID 33028159

Identifiers

NCT: NCT07278141 · 4126162

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗