What method of resistance training has the greatest potential for improving cardiorespiratory endurance?

Circuit training involves sequencing multiple resistance exercises with minimal or no rest intervals between stations, which keeps heart rate continuously elevated in a cardiorespiratory training zone. This combination of muscular demand and sustained cardiovascular stress produces adaptations in both the muscular and cardiorespiratory systems simultaneously. Research supports circuit training as an effective method for improving VO2 max alongside strength in populations where time efficiency is a priority.

Olympic lifting emphasizes maximal power output on individual heavy lifts with substantial rest periods between sets, which does not provide the sustained cardiovascular stimulus needed for cardiorespiratory adaptation.

Split routine training with free weights is organized by muscle group with adequate rest between sets to allow near-maximal strength output, keeping average heart rate too low to drive meaningful cardiorespiratory improvement.

Isokinetic exercise uses specialized dynamometer machines that isolate single joints at controlled speeds, and the brief, isolated nature of these exercises does not sustain the cardiac output necessary for cardiorespiratory endurance gains.