title: Fifteen-day cessation of training on selected physiological and performance variables in women runners.
abstract: This study examined the effects of a 15-day cessation of training on maximal oxygen consumption and selected physiological variables (maximal heart rate, cardiac output [Q], stroke volume [SV], arteriovenous oxygen difference [(a-v)O2 diff], blood plasma concentration) in 15 women middle-distance competitive runners (.VO2max: 49.8 +/- 1.1 ml.kg(-1).min(-1)). Subjects were randomly assigned to a cessation training (CT, n = 7) or maintenance training (MT, n = 8) group and tested every 5 days. Q was measured by CO2 rebreathing from which SV and (a-v)O2 diff were calculated. No significant changes were found at day 5. After 10 days there was a significant decrement in .VO2max (3.8 ml.kg(-1).min(-1)) in the CT group, being significantly lower than MT but no changes thereafter in any physiological variables. Performance (2,400 m) times did not change for MT but was significantly slower (21.5 +/- 7.1 seconds) for the CT group after 15 days, corresponding to the 7.8% decrease in .VO2max. These findings suggest that in competitive women middle-distance runners, actual performance decrements found after 15 days of CT most likely are due to declines in .VO2max.
authors.affiliation: Clinical Research Coordinator, Carol Frank Buck Breast Care Center, University of California at San Francisco, San Francisco, CA 94115, USA.
authors.forename: Roisheen A
authors.initials: RA
authors.lastname: Doherty
authors.forename: J Patrick
authors.initials: JP
authors.lastname: Neary
authors.forename: Yagesh N
authors.initials: YN
authors.lastname: Bhambhani
authors.forename: Howard A
authors.initials: HA
authors.lastname: Wenger
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D002302:Cardiac Output / Q000502:physiology; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics; D006801:Humans; D010101:Oxygen Consumption / Q000502:physiology; D010806:Physical Education and Training; D010953:Plasma Volume / Q000502:physiology; D012420:Running / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology