title: Effects of daily mild supine exercise on physical performance after 20 days bed rest in young persons.
abstract: To investigate the effects of daily mild supine exercise on physical performance capacity identified as maximal oxygen uptake rate (VO2max) after 20 days bedrest, 3 male students performed a supine pedaling at 40% intensity of VO2max for one hour every day, while 6 male and 5 female students were control.  Before and after the bedrest, muscle mass and strength of exercising leg and cardiovascular responses during -40mmHg lower body negative pressure (LBNP) and moderate upright cycling exercise were measured.  Despite the exercise programme VO2max was similarly decreased to the control subjects after bed-rest.  The delta VO2max was correlated to delta % left ventricular fractional shortening during LBNP, and also % delta VO2max to % delta stroke volume of the moderate exercise (both p<0.05).  The exercise programme should be too weak to maintain cardiovascular functions and thus to present the decrease in VO2max against prolonged bedrest as well as weightlessness stress.
authors.affiliation: Department of Health Administration, University of Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Kashihara
authors.forename: K
authors.initials: K
authors.lastname: Takenaka
authors.forename: K
authors.initials: K
authors.lastname: Kawakubo
authors.forename: Y
authors.initials: Y
authors.lastname: Makita
authors.forename: S
authors.initials: S
authors.lastname: Goto
authors.forename: S
authors.initials: S
authors.lastname: Ikawa
authors.forename: A
authors.initials: A
authors.lastname: Gunji
mesh_terms: D000328:Adult; D001510:Bed Rest / Q000009:adverse effects*; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy / Q000379:methods; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008150:Lower Body Negative Pressure; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*; D009200:Myocardial Contraction / Q000502:physiology; D010101:Oxygen Consumption / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology; D013318:Stroke Volume / Q000502:physiology; D016683:Supine Position