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

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

Interventions

OTHER

Mental Fatigue Protocol

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.

OTHER

Upper Extremity Fatigue Protocol

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.

OTHER

Lower Extremity Fatigue Protocol

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.

Sponsors & Collaborators

• Istinye University

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

35 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-11-11

Primary Completion

2026-07-08

Completion

2026-07-08

Countries

• Turkey (Türkiye)

Study Locations