title: Cardiorespiratory responses to stationary running at different cadences in water and on land.
abstract: OBJECTIVE
  The aim of the current study was to analyze the heart rate (HR), oxygen uptake (V.O(2)), and percentage of maximal HR (%HR(max)) and V.O(2) (%V.O(2max)) responses to stationary running exercise performed at different cadences on land (LA) and in water (WA).
  
  
  METHODS
  The sample comprised 12 apparently healthy women (mean age 22.33+/-0.57 years). The exercise was performed in WA and LA environments (interval of 2 hours) at submaximal cadences of 60, 80 and 100 bpm for a period of 4 min at each cadence (interval of 5 min). HR and V.O(2) data were collected using a Polar S610TM and Aerosport KB1-C gas analyzer, respectively. The data were analyzed using factorial ANOVA for mixed models, Tukey's post hoc and Pearson's correlation test, with P<0.05 (SPSS version 13.0).
  
  
  RESULTS
  Significant differences were found between the environments for all variables (HR, V.O(2), %HR(max) and %V.O(2max): P<0.001), with higher values for LA. Significant differences were found between the cadences for all variables (HR, V.O(2), %HR(max) and %V.O(2max): P<0.001). The effect of the interaction environment cadence was only significant for %HR(max) (P=0.041). The correlations between HR and V.O(2) (WA: r=0.857; P<0.001 and LA: r=0.556; P<0.001) and %HR(max) and %V.O(2) (WA: r=0.860; P<0.001 and LA: r=0.798; P<0.001) exhibited high and significant correlation coefficient values, especially for WA, suggesting that variable increased linearly with increases in cadence.
  
  
  CONCLUSIONS
  The results suggest that cardiorespiratory responses to stationary running exercise are lower in WA, though they can be maximized by increasing the execution cadence.
authors.affiliation: Exercise Research Laboratory, School of Physical Education, Federal University of Rio Grande do Sul, Brazil. tinialberton@yahoo.com.br
authors.forename: C L
authors.initials: CL
authors.lastname: Alberton
authors.forename: M P
authors.initials: MP
authors.lastname: Tartaruga
authors.forename: S S
authors.initials: SS
authors.lastname: Pinto
authors.forename: E L
authors.initials: EL
authors.lastname: Cadore
authors.forename: E M
authors.initials: EM
authors.lastname: Da Silva
authors.forename: L F M
authors.initials: LF
authors.lastname: Kruel
mesh_terms: D000222:Adaptation, Physiological; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006339:Heart Rate; D006801:Humans; D010101:Oxygen Consumption; D012420:Running / Q000502:physiology*; D055815:Young Adult