Physiological Responses to Maximal 4-s Sprint Interval Cycling Using Inertial Loading: the Influence of Inter-sprint Recovery Duration

All subjects completed an informed consent for this study that was approved by the Institutional Review Board of the University of Texas at Austin.

Study Overview. A randomized, cross-over experimental design was conducted. Each participant visited the laboratory on four occasions which were separated by two to five days. Measurement of body mass, familiarization with experimental procedures and cycling peak oxygen consumption test (VO2peak) were performed on the first visit. Participants took part in inertial-load exercise (ILE) on the remaining test days. On each separate session, a different inter-sprint recovery duration was employed (i.e. 15, 30 or 45-s). Cycling power output, pulmonary gas exchange, vastus lateralis de-oxygenation status, heart rate and blood lactate were measured.