Electromyostimulation (EMS) of Astronauts in Spaceflight (Easymotion-2) (Easymotion-2)

ElectroMyoStimulation (EMS Body Suit) Protocol to Improve Exercise Outcome in Space Missions (EasyMotion-2)

This is a prospective spaceflight study involving an investigational non-risk device called the EasyMotionSkin for whole body electric muscle (myo) stimulation (WB-EMS) onboard the International Space Station (ISS).

The purpose of this study is to show:

• optimized exercise outcome with EMS in human spaceflight
• demonstrate efficacy of EMS as alternative inflight exercise protocol
• provide a time-saving and reliable EMS-assisted exercise protocol compliant to astronauts for later use in planetary habitats and future deep space exploration

Eight (n=8) astronauts on long duration missions will take part in this study. This experiment uses the following hardware/software (HW & SW): (A) EasymotionSkin suit (dry electrode muscle stimulation), B) non-invasive hand-held Myoton device (digitized passive muscle stiffness data collection). C) a customized Myoton body template suit (elastic yoga suit with customized anatomical reference labels to aid inflight Myoton data collection on dedicated perforated 2x2 cm small skin fields) at 5 different skin measurement points (MP), neck, back, shoulder, legs.

Before and after flight the following tests will be done once: Myoton data collection, dynamometry strength test, magnetic resonance imaging (MRI) for baseline comparison. Researchers will compare data from a non EMS control group (non EMS Astronauts, retrospective) to see if changes of passive muscle stiffness is seen in EMS Astronauts before, during and after spaceflight

Study Overview

• Status: Enrolling by invitation
• Conditions: Muscle Atrophy; Myotonia; Stiffness; Spine; Exercise Overtraining
• Intervention / Treatment: Device: Electromyostimulation (EMS); Device: Myoton; Diagnostic test: Electromyography (EMG); Diagnostic test: Magnetic Resonance Imaging (MRI); Diagnostic test: Dynamometry

Detailed Description

In a previous space analog study (60 days reactive jumps on a sledge during bed rest immobilisation, Cologne, Germany, 2015) on n=24 voluntary participants followed by an experiment on the International Space Station, ISS (MYOTONES 2015-2023) the investigators used non-invasive Myoton technology (Myoton device) to detect digital biomarkers (passive muscle tone and stiffness) on twelve (n=12) study participants together with clinical imaging (MRI), muscle strength tests (dynamometry), and blood samples (biosamples) to study muscle properties and adaptation in microgravity following routine inflight exercise in ISS Astronauts. One of the MYOTONES ISS Astronaut already tested a space-qualified EasymotionSkin suit (Demo-Tech Experiment, German Aerospace Agency, Deutsches Zentrum fuer Luft- und Raumfahrt, DLR, 2022) that was used for about 20 minutes on top of the daily routine exercise protocol in order to optimize inflight training outcome by EMS technology in spaceflight. Preliminary results (n=1) showed feasibility of the novel EMS technology in spaceflight and suggested improved muscle health parameters (increased tone and stiffness) found in some muscle from torso (lower back) and limbs compared to a non-EMS mission crewmember. Easymotion-2 is designed to replicate similar changes in inflight passive muscle parameters (resembling muscle health) in eight (n=8) more ISS Astronauts for robust statistical analyses and interpretation. Pre and postflight baseline data collections with Myoton technology (passive tone [Hz] and stiffness [N/m]) serve as control for comparison. Protocol and recruitment of healthy study participants (male or female Astronauts) is under control by NASA via Informed Consent Briefing standardized procedures.

• Study Type: Interventional
• Enrollment (Estimated): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • State of Berlin
    • Mitte, State of Berlin, Germany, 10117
      • Charité - Universitätsmedizin Berlin

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Astronauts with active Flight Medical

Exclusion Criteria:

• Heart disease
• Liver disease
• Diabetes
• Thrombosis
• Extreme blood pressure
• Abdominal & inguinal hernias (bulges)
• Strong neurological diseases
• Pregnancy
• Cancer

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• 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: EMS (electromyostimulation) participants; Healthy Astronauts that perform EMS-assisted inflight exercise onboard the International Space Station

Device: Electromyostimulation (EMS); EasymotionSkin body suit for digitally controlled electric impulses via Easymotion-2 software on crew iPad (frequency, impulse rate, duration) are transferred from integrated dry electrodes of the EMS- stimulation suit to activate surface muscle groups of the body (trunk), arms and legs; Other Names: EMS body muscle stimulation; Device: Myoton; The non-invasive Myoton technology collects data from passive muscle properties (tone and stiffness) obtained from selected anatomical surface muscle groups; Other Names: passive muscle properties; Diagnostic test: Electromyography (EMG); As a standard method, surface EMG collects data from nerve impulse-triggered active muscle contractions, pre/postflight only; Other Names: surface EMG/nerve impulse rate [amplitude/frequency]; Diagnostic test: Magnetic Resonance Imaging (MRI); MRI is a clinically standard (non-radiation) imaging method to study structural changes of the human body (organs, muscle, bones, tendons) at the macroscopic level, pre/postflight only; Other Names: MRI; Magnetic Resonance Tomography; Diagnostic test: Dynamometry; Dynamometry is a standard functional and diagnostic method to test muscle strength in sports and rehabilitation. pre/postflight only; Other Names: muscle functional test

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Myoton Tone (baseline preflight)	Passive muscle tone [Hz] numerical indices. Abbreviations for Outcome Measures 1-37: Hertz, Hz; Newton/meter, N/m; before launch (preflight), L-; recovery (postflight), R+; inflight days, FD; not earlier than, NET; not later than, NLT; electro-myo-stimulation, EMS; versus/against, vs; surface electromyography, sEMG.	L-105+/-30 days (time window)
Myoton Tone (recovery postflight)	Passive muscle tone [Hz] numerical indices. Abbreviations for Outcome Measures 1-37: Hertz, Hz; Newton/meter, N/m; before launch (preflight), L-; recovery (postflight), R+; inflight days, FD; not earlier than, NET; not later than, NLT; electromyostimulation, EMS; versus/against, vs; surface electromyography, sEMG.	R+30+/-10 days (time window)
Myoton Tone (inflight, preEMS-1)	Passive muscle tone [Hz] numerical indices. Abbreviations: see Outcome1	FD20-30 days (time window)
Myoton Tone (inflight, preEMS-2)	Passive muscle tone [Hz] numerical indices. Abbreviations: see Outcome1	FD60-80 days (time window)
Myoton Tone (inflight, post EMS-1)	Passive muscle tone [Hz] numerical indices. Abbreviations: see Outcome1	NET R-18 days (time window)
Myoton Tone (inflight, post EMS-2)	Passive muscle tone [Hz] numerical indices. Abbreviations: see Outcome1	NLT R-12 days (time window)
Myoton stiffness (baseline, preflight).	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	L-105+/-30 days (time window)
Myoton stiffness (recovery, postflight).	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	R+30+/-10 days (time window)
Myoton stiffness (inflight, preEMS-1)	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	FD20-30 days (time window)
Myoton stiffness (inflight, preEMS-2)	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	FD60-80 days (time window)
Myoton stiffness (inflight, postEMS-1)	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	NET R-18 days (time window)
Myoton stiffness (inflight, postEMS-2)	Passive muscle stiffness [N/m] numerical indices. Abbreviations: see Outcome 1	NLT R-12 days (time window)
EMS body stimulation (inflight EMS1)	1st out of a total of 12 (1/12) single EMS-assisted inflight exercise between NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24. Abbreviations: see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS2)	2/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS3)	3/12 single EMS-assisted inflight exercise, NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out")at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days(time window)
EMS body stimulation (inflight EMS4)	4/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out")at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS5)	5/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out")at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS6)	6/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out")at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS7)	7/12 single EMS-assisted inflight exercise, NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out")at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS8)	8/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS9)	9/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS10)	10/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS11)	11/12 single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
EMS body stimulation (inflight EMS12)	Last out of a total of twelve (12/12) single EMS-assisted inflight exercise NET R-60 and NLT R-21 days (time window) with 1-4 days in between "wash-out") at tolerable stimulation merged to nominal daily inflight exercise countermeasure sessions at crew discretion. Applies to Outcome Measures 13-24: Abbreviations see Outcome 1.	NET R-60 and NLT R-21 days (time window)
Dynamometry (baseline, preflight/power).	Standard muscle isometric/isokinetic tests (power [Watt] on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus). Abbreviations: see Outcome 1	L-105+/-30 days (time window)
Dynamometry (baseline, preflight/torque).	Standard muscle isometric/isokinetic tests ( torque [Nm]) on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus). Abbreviations: see Outcome 1	L-105+/-30 days (time window)
sEMG (baseline, preflight/amplitude).	Non-invasive sEMG by amplitude on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus) as part of dynamometry. Abbreviations: see Outcome 1	L-105+/-30 days (time window)
sEMG (baseline, preflight/frequency).	Non-invasive sEMG by frequency (Hz) on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus) as part of dynamometry. Abbreviations: see Outcome 1	L-105+/-30 days (time window)
Dynamometry (recovery postflight/power).	Standard muscle isometric/isokinetic tests (power [Watt] on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus). Abbreviations: see Outcome 1	R+30+/-10 days (time window)
Dynamometry (recovery postflight/torque).	Standard muscle isometric/isokinetic tests (torque [Nm] on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus). Abbreviations: see Outcome 1	R+30+/-10 days (time window)
sEMG (recovery postflight/amplitude).	Non-invasive surface EMG (amplitude) on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus) as part of dynamometry. Abbreviations: see Outcome 1	R+30+/-10 days (time window)
sEMG (recovery postflight/frequency).	Non-invasive surface EMG (Hz) on calf muscle (gastrocnemius) and lower deep back muscle (erector spinae/multifidus) as part of dynamometry. Abbreviations: see Outcome 1	R+30+/-10 days (time window)
Magnetic Resonance Imaging (MRI) (baseline preflight).	Standard clinical structural analysis by optical sections of lower leg and lumbar back muscle profile/volume area (square/3-D, centimeters). Abbreviations: see Outcome 1	L-105+/-30 days (time window)
Magnetic Resonance Imaging (MRI) (recovery postflight).	Standard clinical structural analysis by optical sections of lower leg and lumbar back muscle profile/volume area (square/3-D, centimeters). Abbreviations: see Outcome 1	R+30+/-10 days (time window)
EMS protocol report (ms)	Multiple measurements (milliseconds=ms) will be aggregated for each of the 12 single inflight EMS session (see Outcome 13-24) to report on inflight EMS protocol and to collect technical data (of muscle stimulation) for whole body inflight EMS monitoring and assessment. see Outcome1	NET R-60 and NLT R-21 days (time window)
EMS protocol report (minutes)	Multiple measurements (duration/min.) will be aggregated for each of the 12 single inflight EMS session (see Outcome 13-24) to report on inflight EMS protocol and to collect technical data (of muscle stimulation) for whole body inflight EMS monitoring and assessment. Abbreviations: see Outcome1	NET R-60 and NLT R-21 days (time window)
EMS protocol report (Hz)	Multiple measurements (frequency/Hz) will be aggregated for each of the 12 single inflight EMS session (see Outcome 13-24) to report on inflight EMS protocol and to collect technical data (of muscle stimulation) for whole body inflight EMS monitoring and assessment. Abbreviations: see Outcome1	NET R-60 and NLT R-21 days (time window)

Collaborators and Investigators

• Sponsor: Charite University, Berlin, Germany
• Collaborators: German Sport University, Cologne
• Investigators: Principal Investigator: Dieter Blottner, PhD, Charite-Universitätsmedizin Berlin, Germany

Publications and helpful links

General Publications

• Schoenrock B, Zander V, Dern S, Limper U, Mulder E, Veraksits A, Viir R, Kramer A, Stokes MJ, Salanova M, Peipsi A, Blottner D. Bed Rest, Exercise Countermeasure and Reconditioning Effects on the Human Resting Muscle Tone System. Front Physiol. 2018 Jul 3;9:810. doi: 10.3389/fphys.2018.00810. eCollection 2018.
• Schoenrock B, Muckelt PE, Hastermann M, Albracht K, MacGregor R, Martin D, Gunga HC, Salanova M, Stokes MJ, Warner MB, Blottner D. Muscle stiffness indicating mission crew health in space. Sci Rep. 2024 Feb 20;14(1):4196. doi: 10.1038/s41598-024-54759-6.
• Muckelt PE, Warner MB, Cheliotis-James T, Muckelt R, Hastermann M, Schoenrock B, Martin D, MacGregor R, Blottner D, Stokes M. Protocol and reference values for minimal detectable change of MyotonPRO and ultrasound imaging measurements of muscle and subcutaneous tissue. Sci Rep. 2022 Aug 11;12(1):13654. doi: 10.1038/s41598-022-17507-2.

Study record dates

Study Major Dates

• Study Start (Actual): September 15, 2025
• Primary Completion (Estimated): July 31, 2029
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: May 23, 2024
• First Submitted That Met QC Criteria: July 1, 2024
• First Posted (Actual): July 9, 2024

Study Record Updates

• Last Update Posted (Actual): March 23, 2026
• Last Update Submitted That Met QC Criteria: March 19, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: skeletal muscle; electromyostimulation; muscle health; passive muscle stiffness; space flight; countermeasure
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Atrophy; Fatigue; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Myotonia; Muscular Atrophy; Overtraining Syndrome; Investigative Techniques; Diagnostic Techniques and Procedures; Diagnosis; Tomography; Diagnostic Imaging; Electrodiagnosis; Myography; Autopsy; Magnetic Resonance Imaging; Electromyography; Postmortem Imaging
• Other Study ID Numbers: 50WB2329

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Results will not be shared to other researchers due to privacy reasons of participating Astronauts related to their Space Agencies

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No