Dose-Response and Phase-Specific Effects of Graded Cognitive Load on Functional Mobility in Older Adults: A Kinematic Analysis (CL)

This study will be conducted to investigate the effect of dose-response and phase-specific effects of Graded Cognitive Load affect on functional mobility in Older Adults

Study Overview

• Status: Not yet recruiting
• Conditions: Older People
• Intervention / Treatment: Other: Dual-Task Cognitive Loading Protocol

Detailed Description

Aging is associated with progressive changes in both the central nervous system and the musculoskeletal system, leading to declines in motor performance, balance, and functional mobility. These changes include reduced cortical processing efficiency, slower information processing speed, and alterations in sensorimotor integration, all of which contribute to decreased movement efficiency in older adults. Functional mobility, particularly walking and transitional movements, is no longer considered a purely automatic motor task, but rather a cognitively mediated activity that requires continuous interaction between attentional resources and motor control systems. Clinically, previous studies have demonstrated that dual-task performance is strongly associated with fall risk and mobility impairment in older adults, suggesting 6 its importance in functional assessment and rehabilitation planning.Despite these advances, most of the existing research has primarily focused on binary dual-task paradigms, comparing single-task versus dual-task conditions without considering different levels of cognitive demand. This approach limits the ability to understand whether cognitive-motor interference follows a dose-response relationship, where progressively increasing cognitive load produces graded deterioration in motor performance. Furthermore, while overall gait and mobility outcomes have been widely investigated, there is a lack of detailed evidence regarding how cognitive load influences specific phases of functional mobility tasks, such as sit-to-stand, gait, turning, and stand-to-sit transitions. Previous studies suggest that different movement phases may vary in their sensitivity to cognitive interference due to differences in biomechanical and postural control demands. However, this phasespecific behavior remains underexplored, particularly in the context of graded cognitive loading.

Therefore, there is a clear gap in the literature regarding the combined effect of graded cognitive load and phase-specific motor behavior during functional mobility tasks.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: mostafa seliem, master; Phone Number: 01554049062; Email: mostafasleim92@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age ≥ 60 years
• Ability to ambulate independently without assistive devices
• Ability to follow verbal instructions and perform dual-task activities
• Medically stable and capable of participating in functional mobility assessment Cognitive function within normal range, defined as Mini-Mental State Examination (MMSE) score ≥ 24 out of 30, indicating absence of significant cognitive impairment .
• Functionqal independence in basic activities of daily living, defined as Barthel Index score ≥ 90 out of 100
• Body Mass Index (BMI) between 18.5 and 29.9 kg/m², as values ≥ 30 kg/m² (obesity) may adversely affect gait and balance performance.

Exclusion Criteria:

• Any neurological disease that affects walking or balance, such as stroke or Parkinson's disease
• Any musculoskeletal condition that limits lower-limb movement or affects normal walking patterns
• Severe cognitive impairment defined as Mini-Mental State Examination (MMSE) score < 24
• Visual, vestibular, or hearing problems that affect safe walking or balance control
• History of lower-limb injury or surgery within the last 6 months
• Serious medical conditions that make participation unsafe, such as unstable cardiac or respiratory disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Dual-Task Cognitive Loading Protocol; sixty Participants will perform the time-up-and-go test under four standardized experimental conditions designed to investigate the dose-response and phase-specific effects of graded cognitive load on functional mobility in older adults.

Other: Dual-Task Cognitive Loading Protocol; Participants will perform the TUG test under four standardized experimental conditions: 1. Single-Task Condition (Baseline) : Participants will perform TUG test without any additional cognitive task. 2-Low Cognitive Load Condition:Participants will perform the TUG test while simultaneously performing simple backward counting by ones starting from a randomly assigned number between 90 and 100. 3-Moderate Cognitive Load Condition :Participants will perform the TUG test while simultaneously performing serial backward counting by threes starting from a randomly assigned number between 90 and 100. 4-High Cognitive Load Condition:Participants will perform the TUG test while simultaneously performing serial subtraction by sevens (Serial 7s task) starting from a randomly assigned number between 90 and 100.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Timed Up and Go (TUG) Completion Time	A smartwatch will be used to assess the completion time of the TUG test. The total time required to complete the TUG test under each cognitive load condition will be recorded in seconds and used as the primary measure of functional mobility performance. Increased TUG completion time will indicate deterioration in functional mobility under cognitive interference conditions	up to one day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
sit-to-stand phase time	A smartwatch will be used to assess the time of sit-to-stand phase as a part of the TUG test	up to one day
walking phase time	The smartwatch will be used to assess the time of the walking phase as a part of TUG test	up to one day
turning phase time	The smartwatch will be used to assess the time of the turning phase as a part of TUG test	up to one day
stand-to-sit phase	The smartwatch will be used to assess the time of the stand-to-sit phase as a part of TUG tes	up to one day
gait speed	A sagittal-plane video-based kinematic analysis system will be used to evaluate gait speed.ormal gait speed for healthy adults generally ranges from 1.2 to 1.4 meters per second (m/s)	up to one day
step length	A sagittal-plane video-based kinematic analysis system will be used to evaluate step length. The normal walking step length is about 2.5 feet (75 to 79 cm) for men and 2.2 feet (66 to 69 cm) for women	up to one day
cadence	A sagittal-plane video-based kinematic analysis system will be used to evaluate cadence. A normal comfortable walking cadence for healthy adults generally ranges from 100 to 120 steps per minute	up to one day
step time	A sagittal-plane video-based kinematic analysis system will be used to evaluate step time. the normal step time for a healthy adult walking at a comfortable, self-selected speed is approximately 0.5 seconds per single step	up to one day
turning duration	A sagittal-plane video-based kinematic analysis system will be used to evaluate turning duration.For healthy, normal adults, the average turning durations typically fall into these ranges from 1.4 to 1.5 seconds	up to one day
peak trunk flexion angle	sagittal-plane video-based kinematic analysis system will be used to evaluate peak trunk flexion.Studies show that actively flexing the trunk increases peak angles (reaching higher ranges like an added 47° in intentional flexed landings vs. preferred landings) which helps absorb impact and protect the knees	up to one day
peak hip flexion angle	the sagittal-plane video-based kinematic analysis system will be used to evaluate peak hip flexion angle. it should be from 130-140 degree.	up to one day
peak knee flexion angle	The sagittal-plane video-based kinematic analysis system will be used to evaluate peak knee flexion angle. it should be from 120-150 degree.	up to one day

Collaborators and Investigators

• Sponsor: Cairo University

Study record dates

Study Major Dates

• Study Start (Estimated): September 20, 2026
• Primary Completion (Estimated): February 20, 2027
• Study Completion (Estimated): February 20, 2027

Study Registration Dates

• First Submitted: September 5, 2026
• First Submitted That Met QC Criteria: September 5, 2026
• First Posted (Actual): September 10, 2026

Study Record Updates

• Last Update Posted (Actual): September 10, 2026
• Last Update Submitted That Met QC Criteria: September 5, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Keywords: Older Adults; Functional Mobility; Dose-Response and Phase-Specific; Graded Cognitive Load
• Other Study ID Numbers: P.T.REC/012/006633

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No