Individualised training at different intensities, in untrained participants, results in similar physiological and performance benefits

The impact of individualising exercise duration on training adaptations has not been explored, in particular when comparing different intensities of exercise. This study compared effects of training at moderate, high, or a combination of the two intensities (mixed) on performance and physiological adaptations, when training durations were individualised. 34 untrained participants were assigned to a moderate, high, or mixed group. Maximal oxygen uptake (V?O2max), power output at V? 43 O2max (MAP), time-to-exhaustion and cycling gross efficiency were recorded before and after four weeks of supervised cycling training (four times per week). The moderate group cycled at 60% MAP in blocks of 5 min with 1 min recovery, and training duration was individualised to 100% of pre-training time-to-exhaustion. The high group cycled at 100% MAP for 2 min with 3 min recovery, and training duration was set as the maximum number of repetitions completed in the first training session. The mixed group completed two moderate- and two high-intensity sessions each week, on alternate days. The V?O2max (d = 0.29; 0.59; 0.29), MAP (d = 0.45; 0.63; 0.61), time-to-exhaustion (d = 1.18; 0.88; 1.00) and cycling gross efficiency at 50% MAP (d = 0.19; 0.11; 1.06) increased after four weeks of moderate-, high- and mixed-intensity training respectively (P<0.05), but there were no differences between groups (P>0.05). When training durations are individualised in untrained participants, similar improvements in performance and physiological measures occur, despite differences in exercise intensity.