NM Balance Regulation With ULLS and Loss of Sleep

NCT05956964 | Completed Results

• 2 other identifiers: 8429080NSSC20M004
• Study Type: interventional
• Target: 16
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this trial is to learn about how restricted sleep and not bearing weight on the leg affects muscle strength and posture control. Participants will walk exclusively on one leg, sleep at differing intervals, and complete posture tests, muscle strength tests, and muscle imaging. Researchers will compare adequate sleep and restricted sleep to see if muscle strength and posture are affected.

Conditions

Muscle Weakness; Quadriceps Muscle Atrophy; Sleep Disturbance

Keywords

sleep restriction; spaceflight; unweighting; posture

Outcome Measures

Primary Outcomes (4)

• Change in Percentage in Interpolated Twitch Torque of the Loaded and Unloaded Leg

  Subjects will sit upright in an isokinetic dynamometer with the knee at 60° flexion. Gel electrode pads will be placed over the femoral nerve and just proximal to the patellar tendon. Square wave, constant current, doublet pulses from an electrical stimulator will be used to evoke twitches prior to, during, and following a maximal voluntary isometric contraction (MVIC). Twitch torque will be measured in Newton-meters (Nm). Outcome data are reported as the percentage change in voluntary activation from baseline.

  Baseline and study completion, approximately 14 days

• Percent Change in Single Leg Stand (SLS)

  Balance will be assessed using a dual force plate system. Participants will be asked to stand on one leg and maintain their balance for 15 seconds. Specific outcome measures include percentage change in center of pressure 95% ellipse area (sq. mm) compared to baseline.

  Baseline and study completion, approximately 14 days

• Muscle Volume

  Diffusion Tensor Imaging (DTI) will be used to quantify muscle volume of the loaded and unloaded leg. Subjects will lay supine, and slightly flex the knee (\~10°) to elongate and straighten the quadriceps. A spine array coil will be placed on the MR-scanner table and a flexible body coil wrapped around the upper thigh and centered over mid-thigh of the dominant leg. Multiple images will be taken. DSI Studio program will be used to analyze raw images.

  Post-intervention, approximately 14 days after start of study

• Percent Change in Center of Pressure Velocity During Single Leg Stance

  Balance will be assessed using a dual force plate system. Participants will stand on one leg on a stable force deck for 15 seconds. The mean Center of Pressure (CoP) velocity will be measured in millimeters per second (mm/s) for loaded and unloaded limbs. Outcomes are reported as the percentage change in mean velocity compared to pre-intervention.

  Baseline and study completion, approximately 14 days

Study Arms (2)

Sleep Restriction (SR)

EXPERIMENTAL

The research team will provide participants with a pair of shoes to wear throughout the study. The right shoe will be modified to include a 5cm (approximately 2") rocker-style platform which will keep the left leg suspended during walking. Participants will also be provided with a pair of short crutches to assist with walking. Participants in the SR group will sleep only 5 hours for three consecutive nights.

Behavioral: Sleep Restriction

Sleep Adequate (SA)

ACTIVE COMPARATOR

The research team will provide participants with a pair of shoes to wear throughout the study. The right shoe will be modified to include a 5cm (approximately 2") rocker-style platform which will keep the left leg suspended during walking. Participants will also be provided with a pair of short crutches to assist with walking. Participants in the SA group will sleep for 9 hours for three consecutive nights.

Behavioral: Sleep Adequate

Interventions

Sleep Adequate BEHAVIORAL

9 hours of sleep for 3 days

Sleep Adequate (SA)

Sleep Restriction BEHAVIORAL

5 hours of sleep for 3 days

Sleep Restriction (SR)

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age between 18 and 50 years
• Regularly engaging in aerobic exercise (\> 150min/wk) and resistance exercise (\>1 time per week) for the past 12 months
• Regularly sleep at least 7 hours per night

You may not qualify if:

• Age \< 18 or \> 50 years
• Height between \<150 (F) or \<170 (M) and \> 190 cm (both sexes)
• Waist circumference \< 55cm or \> 90cm (F) and \< 75cm or \> 100cm (M)
• Body mass index \< 18.5 or \> 27.5
• Do not regularly sleep between 7 and 9 hours each night
• Have a known sleep disorder
• Not regularly engaging in exercise for previous 12 months
• Blood clotting disorder
• Heart arrhythmia
• Implanted device which could negatively be affected by electrical impulse or strong magnetic field such as pacemaker, internal defibrillator, or cochlear implant
• Diagnosed cardiovascular, pulmonary, renal, or metabolic disease
• Pregnancy (within previous 6 months)
• Oral contraceptive use (within previous three months)
• High resting blood pressure (\>140 systolic and/or \> 90 diastolic)
• Currently or previously undergone gender-affirming therapy (hormone therapy or sexual reassignment surgery)

Sponsors & Collaborators

• Lance Bollinger: lead
• National Aeronautics and Space Administration (NASA): collaborator

Study Sites (1)

University of Kentucky

Lexington, Kentucky, 40506, United States

Location

MeSH Terms

Conditions

Muscle Weakness; Parasomnias

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Neuromuscular Manifestations; Neurologic Manifestations; Nervous System Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Sleep Wake Disorders; Mental Disorders

Results Point of Contact

• Title: Dr. Lance Bollinger
• Organization: University of Kentucky

lance.bollinger@uky.edu

859-257-7904

Study Officials

• Lance Bollinger, PhD

  University of Kentucky

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Associate Professor

Model Details: Subjects will be randomized to different arms via a matched-pairs design using the following criteria: age, sex, and race. Within each arm, the loaded limb will serve as an internal control to assess effects of unloading.

Study Record Dates

• First Submitted: July 3, 2023
• First Posted: July 24, 2023
• Study Start: August 10, 2023
• Primary Completion: March 14, 2025
• Study Completion: March 14, 2025
• Last Updated: June 17, 2026
• Results First Posted: June 17, 2026

Record last verified: 2026-05

Locations

US (1)