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Motorized and Non-Motorized Treadmill Evaluation: Physiologic Responses and Biomechanical Aspects (ROI_Locomotion)
Principal Investigator
Research Area:
Cardiovascular physiology
Exercise physiology
Muscle physiology
Species Studied
Scientific Name: Homo sapiens Species: Human

Treadmill exercise is currently employed as a countermeasure to space flight de-conditioning during long duration missions aboard the International Space Station (ISS). The primary treadmill currently in use, a space flight treadmill with vibration isolation and stabilization (TVIS), can be operated in either motorized (TVIS-M) or non-motorized (TVIS-NM) modes. Although nominal treadmill exercise is performed in the motorized mode, non-motorized treadmill exercise has been utilized as a contingency situation in case of treadmill motor failure or low power availability for treadmill operation. Additionally, a Russian non-motorized treadmill (BD-1) has been proposed as a contingency exercise device in the event of a TVIS failure.

Although previous studies have demonstrated differences between motorized and non-motorized treadmill exercise, there has been no direct comparisons made between exercise hardware designed for space flight. Little is known about any differences in metabolic demand, muscle work, gait kinematics, and ground reaction forces between motorized and non-motorized treadmill exercise.

The purpose of this study is to compare the acute metabolic and cardiovascular responses, as well as the kinetic and kinematic aspects of short-duration TVIS-M, TVIS-NM, and BD-1 treadmill exercise in relation to a standard laboratory treadmill (LAB-TM) exercise. The findings from this study provide valuable information regarding ongoing use of treadmill exercise as a countermeasure to musculoskeletal and cardiovascular de-conditioning associated with space flight and assist in the development of future treadmill exercise prescriptions.

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De Witt JK, Bentley JR, Lee SM, Norcross J, Smith C, Hagan, RD. Kinematic differences between motorized and nonmotorized treadmill locomotion: Paper presented at: American Society of Biomechanics Annual Meeting; September 6-9, 2006; Blacksburg, VA. NASA Technical Memorandum NASA/TM-2006-0021459.

De Witt JK, Lee SM, Wilson CA, Hagan RD. Determinants of time to fatigue during nonmotorized treadmill exercise. Journal of Strength and Conditioning Research. 2009 May; 23(3):883-90.[]

Lee SM, De Witt JK, Smith C, Laughlin MS, Loehr JA, Norcross J, Hagan RD. Physiologic responses and biomechanical aspects of motorized and non-motorized treadmill exercise: a ground-based evaluation of treadmills for use on the International Space Station. Houston TX: National Aeronautics and Space Administration, Lyndon B. Johnson Space Center; 2006. NASA Technical Publication NASA/TP-2006-0052414.

Comparative study
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Data Information
Data Availability
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Absolute oxygen consumption
Ankle angle at heel strike
Ankle angle at toe off
Ankle range of motion
Blood lactate
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Mission/Study Information
Mission Launch/Start Date Landing/End Date Duration
ROI 01/01/2002 12/31/2012 In Progress

Additional Information
Managing NASA Center
Johnson Space Center (JSC)
Responsible NASA Representative
Johnson Space Center LSDA Office
Project Manager: Jessica Keune
Institutional Support
National Aeronautics and Space Administration (NASA)
Alternate Experiment Name