Table 1 Inclusion criteria according to the PICOS approach

Population

Healthy trained and untrained humans aged > 14 years old

Intervention

Interval exercise training using passive or active recovery types during exercise for at least 3 weeks

Comparator

Active and/or passive controls

Outcomes

Measures of physical fitness (e.g., aerobic performance, jump performance etc.), physiological adaptations (e.g., maximal oxygen uptake [VO_2max], maximal aerobic speed [MAS], lactate threshold, running economy etc.)

Study Design

nRCTs, nRnCTs and RCTs