Muscular Fatigue vs. Mental Fatigue on Balance, Proprioception and Reaction Time

NCT07620860 | Recruiting

• 1 other identifier: ISU-25-099
• Study Type: interventional
• Target: 66
• Locations: 1 country
• Sites: 1

Brief Summary

This study aims to understand how different types of fatigue affect balance and reaction time, proprioception, and fine motor in healthy young adults. Fatigue is a common experience in daily life and can arise from physical activity or prolonged mental effort. The study seeks to determine whether fatigue of the upper body, lower body, or mental fatigue from cognitively demanding tasks can negatively affect balance and reaction time, proprioception, and fine motor abilities. To examine this, participants will undergo controlled fatigue protocols designed to tire specific parts of the body or the mind. the Upper body fatigue will be induced through repeated maximal push-up sets performed until the participant can no longer maintain proper form. Lower body fatigue will be created through repeated maximal 1-minute squat jump sets, with participants touching a low box to ensure standardized depth and proper movement. Mental fatigue will be induced using a 20-minute computer-based cognitive task that alternates between the 2-back working memory task and the numerical Stroop task. These tasks are designed to require continuous attention, mental effort, and inhibitory control. Each type of fatigue will be induced independently, and participants' performance will be measured before and after each fatigue protocol. Following fatigue induction, participants will complete a series of tests designed to assess balance and reaction time, proprioception, and fine motor abilities. This includes both static and dynamic postural tasks, as well as reaction time and proprioceptive accuracy assessments. By evaluating these measures before and after fatigue, the study will determine how different forms of physical and mental fatigue impact postural stability, sensory processing, and precise motor control. The study addresses the question: "Do upper body fatigue, lower body fatigue, or mental fatigue reduce balance and reaction time, proprioception, and fine motor performance in healthy young adults?" The hypothesis is that each form of fatigue upper body, lower body, or mental-will meaningfully impair balance and reaction time, proprioception, and fine motor performance compared to non-fatigued conditions.

Conditions

Mental Fatigue; Muscular Fatigue

Keywords

fatigue; reaction time; balance; cognitive

Outcome Measures

Primary Outcomes (3)

• Y Balance Test (YBT)

  The assessment will be performed using a standard YBT kit, which includes a central stance platform and three measurement tapes extending in the anterior (ANT), posteromedial (PM), and posterolateral (PL) directions. Participants will stand barefoot on their dominant leg on the central platform. While maintaining balance and keeping the stance foot stationary, they will reach as far as possible in each of the three directions with the contralateral leg to push a reach indicator. To ensure maximum performance, three trials will be conducted for each direction, and the best score (maximum reach distance) will be recorded for analysis.

  Day 1

• BlazePod Reaction System for Lower Extremity

  Four pods will be arranged in a square configuration at a distance equal to the participant's leg length. Participants stand barefoot in the center on one leg for 30 seconds. They must tap the illuminated pods with their raised foot as quickly as possible without the raised foot touching the ground more than once.

  Day 1

• BlazePod Reaction System for Upper Extremity

  Four pods will be arranged in a rectangular layout (91 cm long and 30 cm wide), with two pods on each side. The protocol follows the same principles as the lower extremity test. Performance is measured by the total number of "hits" and the average RT between responses.

  Day 1

Secondary Outcomes (3)

• Ruler Drop Reaction Test

  Day 1

• Purdue Pegboard Test (PPT)

  Day 1

• Joint Position Sense Test (JPS Test)

  Day 1

Study Arms (3)

Upper Extremity Fatigue

EXPERIMENTAL

Other: Upper Extremity Fatigue Protocol

Lower Extremity Fatigue

EXPERIMENTAL

Other: Lower Extremity Fatigue Protocol

Mental Fatigue

EXPERIMENTAL

Other: Mental Fatigue Protocol

Interventions

Mental Fatigue Protocol OTHER

Mental Fatigue will be created by administering a continuous 20-minute computerized cognitive protocol composed of four consecutive 5-minute blocks without rest. The 2-back task (5 minutes) and the numerical Stroop task (5 minutes) will each be performed twice in alternating order. The sustained and repeated working memory and inhibitory control demands are intended to induce progressive cognitive load and mental fatigue.

Mental Fatigue

Upper Extremity Fatigue Protocol OTHER

The upper extremity fatigue will be created by requiring participants to perform consecutive sets of push-ups until task failure. Push-ups will be executed according to standardized ACSM guidelines, and repetitions will be recorded. Participants will first complete one maximal set to exhaustion, followed by a 1-minute rest period and a second maximal set. If performance in the second set exceeds 60% of the initial repetition count, additional sets will be performed after 1-minute recovery intervals. This sequence will continue until the participant's performance declines below 60% of the previous set, at which point neuromuscular fatigue will be considered achieved.

Upper Extremity Fatigue

Lower Extremity Fatigue Protocol OTHER

The lower extremity fatigue will be created by requiring participants to perform repeated 1-minute sets of maximal squat jumps until exhaustion. During each jump, participants will execute countermovement jumps and touch a low box with their hips to ensure standardized depth, under researcher supervision for proper technique. After completing an initial 1-minute maximal set, total jump count will be recorded. Following a 1-minute recovery period, a second 1-minute maximal set will be performed. If performance in the second set exceeds 60% of the first set's total repetitions, additional 1-minute sets will be completed after 1-minute rest intervals. This procedure will continue until jump performance declines below 60% of the previous set, at which point neuromuscular fatigue will be considered achieved.

Lower Extremity Fatigue

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Being between 18 and 35 years of age
• Self-reporting good general health status
• Not having any physician-diagnosed medical condition
• Not using any assistive device or orthotic insoles

You may not qualify if:

• History of neurological disorders affecting balance (e.g., stroke, Parkinson's disease, multiple sclerosis, vestibular disorders)
• Current or recent (within the past 6 months) lower extremity or spinal injury
• Current lower extremity pain
• Uncontrolled cardiovascular disease
• Uncorrected visual impairment affecting balance
• Current pregnancy

Sponsors & Collaborators

• Istinye University: lead

Study Sites (1)

Istinye University Research and Application Center (ISUFIZYOTEM)

Istanbul, Turkey (Türkiye)

RECRUITING

MeSH Terms

Conditions

Mental Fatigue; Fatigue

Condition Hierarchy (Ancestors)

Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Behavioral Symptoms; Behavior

Central Study Contacts

Çiçek Günday, PhD

CONTACT

0850 283 6000; cicek.gunday@istinye.edu.tr

Alaa Aldeen Hamwi, PT

CONTACT

0850 283 6000; alaa.hamwi@stu.istinye.edu.tr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: INVESTIGATOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Asst. Prof.

Study Record Dates

• First Submitted: March 31, 2026
• First Posted: June 2, 2026
• Study Start: November 11, 2025
• Primary Completion (Estimated): July 30, 2026
• Study Completion (Estimated): July 30, 2026
• Last Updated: June 2, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)