Purpose Improvements in D'(the fatigability constant for running)subsequent to training interventions remain elusive.High-intensity interval training(HIIT)within the severe intensity domain for short durations(<...Purpose Improvements in D'(the fatigability constant for running)subsequent to training interventions remain elusive.High-intensity interval training(HIIT)within the severe intensity domain for short durations(<2-min)have been theorized to improve D'.The purpose of the present study was to assess this in a group of moderately trained individuals.Methods Eighteen participants completed graded exercise testing(GXT),40-m sprint testing and a 3-min all-out test(3MT)for running to determine key mechanistic and physiological parameters.Participants were randomly assigned into one of two groups based on intensity prescription(G140%=140%of critical speed[CS]),or time intervals(G90-s=90-s)to complete a twice-weekly training intervention for 6-weeks followed by re-assessment.Results No between-group differences were present either prior to or following the intervention.Substantial and meaning-ful improvements were detected during the post-intervention period for both groups for VO2max(G140%:+7.60%;G90-s:+11.67%),speed evoking VO2max(sVO2max;G140%:+4.33%;G90_s:+2.92%),gas exchange threshold(GET;G140%:+12.02%;G90-s:+20.52%),speed evoking GET(sGET;G140%:+4.17%;G90_s:+7.92%),CS(G140%:M=0.62 m/s;G90-s:M=0.46 m/s),D'(G140%:M=-56.34 m;G90-s:M=-18.36 m),FI%(G140%M=-6.75%;G90-s:M=-4.38%)and maximal distance(G140%:M=49.67 m;G90_s:M=58.38 m).Conclusions The prescribed intensities and durations were insufficient to elicit improvements in D'.Improvements in D'may be dependent on very short-duration intervals(i.e.<60 to 90-s)at speeds exceeding 140%CS but below maximal sprint speed.展开更多
文摘Purpose Improvements in D'(the fatigability constant for running)subsequent to training interventions remain elusive.High-intensity interval training(HIIT)within the severe intensity domain for short durations(<2-min)have been theorized to improve D'.The purpose of the present study was to assess this in a group of moderately trained individuals.Methods Eighteen participants completed graded exercise testing(GXT),40-m sprint testing and a 3-min all-out test(3MT)for running to determine key mechanistic and physiological parameters.Participants were randomly assigned into one of two groups based on intensity prescription(G140%=140%of critical speed[CS]),or time intervals(G90-s=90-s)to complete a twice-weekly training intervention for 6-weeks followed by re-assessment.Results No between-group differences were present either prior to or following the intervention.Substantial and meaning-ful improvements were detected during the post-intervention period for both groups for VO2max(G140%:+7.60%;G90-s:+11.67%),speed evoking VO2max(sVO2max;G140%:+4.33%;G90_s:+2.92%),gas exchange threshold(GET;G140%:+12.02%;G90-s:+20.52%),speed evoking GET(sGET;G140%:+4.17%;G90_s:+7.92%),CS(G140%:M=0.62 m/s;G90-s:M=0.46 m/s),D'(G140%:M=-56.34 m;G90-s:M=-18.36 m),FI%(G140%M=-6.75%;G90-s:M=-4.38%)and maximal distance(G140%:M=49.67 m;G90_s:M=58.38 m).Conclusions The prescribed intensities and durations were insufficient to elicit improvements in D'.Improvements in D'may be dependent on very short-duration intervals(i.e.<60 to 90-s)at speeds exceeding 140%CS but below maximal sprint speed.
