The research article by Foster et al. (2015) aimed to compare high intensity interval training (HIIT) protocols with steady state exercise and conclude that HIIT protocols are not superior to conventional exercise training in sedentary young adults. We would like to compliment the authors for the interesting work and findings, however, it is necessary to point out some relevant issues, especially regarding protocols configuration and interpretation of the results. Despite the worldwide popularity of Tabata’s protocol, it is necessary to be more critical about its use and adaptation. Foster et al. (2015) cited Tabata et al. (1996) for the very brief, very high intensity interval training used in the study. However, they actually described a protocol similar to the one published by Tabata et al. (1997), which should be performed until exhaustion with only 5–6 bouts at 170% of the VO2max, and not 8 as used in the study. The original protocol, published in 1996, proposed 7–8 sprints at a constant load performed until the pedaling frequency dropped below 85 rpm. Load was incremented when the participants could perform more than 9 sets, and not only based on RPE decrements. The Meyer et al. (1990) interval training protocol used by Foster et al. (2015) also did not follow the original description. The original prescription was based on maximum heart rate (86 ± 3% of maximum), with 1-min intervals and an effort:pause ratio of 1:1, while the protocol described by Foster et al. (2015) was based on power output (PO), with 30-s intervals and an effort:pause ratio of 1:2. In our opinion, researchers should exercise caution when attempting to replicate previously used protocols, since deliberate changes to these original parameters used will most likely yield different results. In addition, the divergence between the used protocols from the protocols cited in the references may cause difficulties when replicating the study. Therefore, authors should be more meticulous in indicating these changes and their consequent limitations. Moreover, one of the major problems with HIIT studies is the wide range of training protocols utilized across studies, limiting more conclusive inferences. In this way the modification of existing protocols in subsequent studies does not contribute positively to increase our comprehension about HIIT prescription