Universität zu Köln

Yilmaz, Kenan, Burnley, Mark ORCID: 0000-0003-3407-561X, Boecker, Jonas, Mueller, Klaus, Jones, Andrew M. and Rittweger, Joern (2021). Influence of simulated hypogravity on oxygen uptake during treadmill running. PHYSIOL. REP., 9 (9). HOBOKEN: WILEY. ISSN 2051-817X

Full text not available from this repository.

Abstract

Prolonged exposure to microgravity during spaceflights leads to severe deterioration in the physical performance of astronauts. To understand the effectiveness of existing in-flight daily countermeasures and to plan exercise onboard the International Space Station, we compared supine treadmill running to traditional upright treadmill running on earth. Specifically, we assessed the cardiorespiratory responses to conventional upright running to the responses to supine treadmill running under 0.3 g, 0.6 g, and 1 g of body weight in younger (20-30 years, n = 14, 8 females) and older healthy adults (50-60 years, n = 12, 6 females). Maximal cardiorespiratory capacity was additionally evaluated by performing an incremental running protocol on each treadmill. Maximum speed was greater for 0.3 g and 0.6 g in supine than for upright running (18.5 km/h (1.1) and 15.9 (3.1) vs 13.2 (2.4) p < 0.001). In contrast, maximum oxygen uptake ((V)over dotO(2max)) and maximum heart rate (HRmax) were greater in upright running than in all supine conditions (Upright treadmill running vs S1.0G vs S0.6G vs S0.3G, 41.7 ml kg(-1) min(-1) (7.2) vs 30.5 (6.6) vs 32.9 (7.0) vs 30.9 (5.2), p < 0.001 and 171 beats min(-1) (14) vs 152 (24) vs 155 (20) vs 152 (18), p < 0.001, respectively). The reduction in (V)over dotO(2max) was remarkably similar across all three supine conditions, could not be increased by higher running speeds and can be well explained by reduced ground reaction forces (GRF). Thus, although a gravity-related restriction of pulmonary gas exchange or perfusion of the legs when exercising in the supine position can be suspected, findings are also explicable on grounds of the vertical treadmill mechanics. Reduced loading will constitute a substantial limitation to (V)over dotO(2) in space with implications for crew health and the physical deterioration of astronauts.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Yilmaz, Kenan UNSPECIFIED UNSPECIFIED UNSPECIFIED Burnley, Mark UNSPECIFIED orcid.org/0000-0003-3407-561X UNSPECIFIED Boecker, Jonas UNSPECIFIED UNSPECIFIED UNSPECIFIED Mueller, Klaus UNSPECIFIED UNSPECIFIED UNSPECIFIED Jones, Andrew M. UNSPECIFIED UNSPECIFIED UNSPECIFIED Rittweger, Joern UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-588588
DOI:	10.14814/phy2.14787
Journal or Publication Title:	PHYSIOL. REP.
Volume:	9
Number:	9
Date:	2021
Publisher:	WILEY
Place of Publication:	HOBOKEN
ISSN:	2051-817X
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language ORTHOSTATIC INTOLERANCE; MUSCLE PUMP; FOOT FORCES; EXERCISE; SPACE; CYCLE; WEIGHTLESSNESS; COUNTERMEASURE; SPACEFLIGHT; ADAPTATION Multiple languages Physiology Multiple languages
URI:	http://kups.ub.uni-koeln.de/id/eprint/58858