Recruiting

Mental Fatigue

Sponsor:

Florida Institute for Human and Machine Cognition

Code:

NCT07846618

Conditions

Mental Fatigue

Muscle Strength Dynamometer

Eligibility Criteria

Sex: All

Age: 18 - 39

Healthy Volunteers: Accepted

Interventions

Computer-Based Mental Fatigue Protocol

Study Details

Brief summary:

This study will investigate the acute effects of mental fatigue on lower-extremity muscle strength and limb symmetry in healthy young adults. Participants will complete lower-extremity strength testing before and after a standardized computer-based mental fatigue protocol involving tasks of attention, reaction time, concentration, and working memory. Muscle strength and limb symmetry will be assessed using isokinetic dynamometry, with muscle activity measured using surface electromyography. Participants will also complete subjective measures of mental fatigue, sleepiness, mental effort, and perceived physical exertion. Heart rate will be monitored throughout the study, and brain activity may be assessed during cognitive tasks. The study will determine whether acute mental fatigue is associated with changes in muscle strength, limb symmetry, and neuromuscular performance.

Conditions

Mental Fatigue

Muscle Strength Dynamometer

Study ID

NCT07846618

Start date

Sep 23, 2026

Status verified date

Sep, 2026

Completion date

Dec 31, 2027

Anticipated

Primary completion date

Dec 31, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 39

Healthy Volunteers: Accepted

Inclusion Criteria:

1. Age 18-39 years
2. Able to produce maximal force against Biodex protocol
3. Able to perform required lower extremity movements through range of motion necessary for Biodex protocol
4. No known cognitive impairment
5. Sufficient musculoskeletal health to complete the tasks

Exclusion Criteria:

1. History of a neurological disorder, disease, or cognitive impairment that may affect cognition, motor control, reaction time, or force production
2. History of musculoskeletal injury affecting the lower extremities within the past 6 months
3. History of lower extremity surgery affecting force production of the hip, knee, or ankle
4. Color-vision impairment
5. Significant visual or hearing impairment
6. History of migraine headaches
7. Current significant sleep disturbances or sleep deprivation
8. Head injury that may affect cognitive function
9. Medical condition affecting ability to produce maximal force safely
10. Allergy to adhesive tape, parabens, or propylene glycol
11. Scalp lacerations, open wounds, or sutures on the scalp
12. Cranial surgery or skull defects
13. History of unexplained dizziness or fainting in the past 6 months
14. Individuals who are pregnant, prisoners, or not yet adults
15. Inability to communicate with investigators
16. Inability to provide written informed consent

Study Design

Enrollment

50 participants

Anticipated

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Mental Fatigue Intervention

Participants will complete baseline lower-extremity muscle strength testing followed by approximately 30 minutes of standardized computer-based cognitive tasks designed to induce acute mental fatigue. Lower-extremity muscle strength testing will then be repeated immediately following the mental fatigue intervention.

Interventions

Computer-Based Mental Fatigue Protocol

Participants will complete approximately 30 minutes of standardized computer-based cognitive tasks designed to induce acute mental fatigue. The tasks require sustained attention, concentration, reaction time, working memory, and mental effort and may include the Psychomotor Vigilance Task (PVT), incongruent Stroop task, and n-back task. Participants will complete the mental fatigue protocol after baseline strength testing and before the post-intervention strength assessment. Subjective mental fatigue and sleepiness will be assessed before and after the intervention, and perceived mental effort will be assessed following the intervention.

Primary outcome measure

  • Lower-Extremity Muscle Strength [ Time Frame: Baseline and immediately following the approximately 30-minute mental fatigue intervention, during a single study visit lasting up to 2 hours. ]
  • Lower-Extremity Limb Symmetry [ Time Frame: Baseline and immediately following the approximately 30-minute mental fatigue intervention, during a single study visit lasting up to 2 hours. ]

Central Contacts and Locations

Central contacts

Nicole K Rendos, PhD

850-202-4442nrendos@ihmc.org

Locations

Florida Institute for Human and Machine Cognition

Recruiting

Pensacola, Florida, United States, 32502

Contacts

Nicole Rendos, PhD

850-202-4442nrendos@ihmc.org

More Information

Sponsor

Florida Institute for Human and Machine Cognition

Last update posted

Sep 29, 2026

Last verified

Sep, 2026

Keywords

  • mental fatigue
  • muscle strength
  • limb symmetry
  • isokinetic dynamometry
  • electromyography

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-30. This information was provided to ClinicalTrials.gov by Florida Institute for Human and Machine Cognition on 2026-09-29. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.