Table 3

Differences in WT and RT runners for physiological variables assessed during the high-intensity interval sequence

WTRTEffect sizeQualitative threshold
VO24th minute66.0±2.648.3±3.52.92±0.80Very large increase
EE (kJkg)38.1±1.9228.6±1.882.71±0.84Very large increase
RER0.88±0.010.95±0.01−2.69±0.80Very large decrease
Lactate (mmol/L)7.6±1.66.5±1.70.43±0.81Unclear
  • Data are presented as mean and 90% (CL). Effect size is shown as 90% CL WT to RT.

  • RPE, RER and blood lactate concentrations were measured during the work periods.

  • CL, confidence limits; EE, energy expenditure during work and rest periods; RER, respiratory exchange ratio; RPE, rating of perceived exertion; RT, recreationally trained; VO24th minute, VO2 (mL/kg/min) during the fourth minute of each work period; WT, well-trained.