HIIT can be steered to a target adaptation by manipulating up to nine session variables
The canonical framework for prescribing interval conditioning (Part I: cardiopulmonary emphasis)
Key Findings
HIIT prescription consists of manipulating up to nine variables: work-interval intensity and duration, relief-interval intensity and duration, exercise modality, number of repetitions, number of series, and between-series recovery duration and intensity. Changing any of them changes the acute physiological response.
The authors' working target for maximal cardiovascular and peripheral adaptation: at least several minutes per session in the "red zone", i.e. at or above 90% of VO2max (time at VO2max, T@VO2max).
Besides T@VO2max, a HIIT stimulus should also be characterised by cardiovascular work, anaerobic glycolytic contribution, and acute neuromuscular load / musculoskeletal strain (the last two are covered in Part II).
For team and racquet sport players, including sprints and all-out efforts in HIIT has also been effective.
Practical Application
Buchheit & Laursen's framework: HIIT is not one thing — up to nine variables (work and relief intensity/duration, modality, repetitions, series, between-series recovery) set the stimulus, and for cardiopulmonary development the aim is several minutes per session at ≥90% VO2max — design the format to the system you want to load.
Typical mapping (full text; not checked against the abstract): long intervals for cardiopulmonary strain, short/short formats for accumulating time near VO2max, sprints for anaerobic/neuromuscular load.
Inference, not tested: change one variable at a time to shift the stimulus deliberately.
Limitations
Framework/expert synthesis, not a meta-analysis; individual responses to a given format vary.
How this entry was checked and changed
Content correction 2026-09-27
Variable list corrected to the abstract's nine (reps, series, between-series recovery duration and intensity); removed "series duration" and "prior/interspersed condition", which the abstract does not list.
Added the abstract's ≥90% VO2max / several-minutes target and the other stimulus descriptors; Sport "conditioning" -> "general".
Format-to-system mapping labelled as full text; "one variable at a time" labelled as inference.