Choose the purpose, control the effort and judge the quality of the work. The interval format is only the starting point.
Two athletes finish the same session: 20 repetitions of 30 seconds, with 30 seconds of recovery. One runs smoothly and could have completed a few more. The other sprints the first repetitions, loses speed and spends the final minutes fighting to finish. Their watches show the same workout. The training they have done is different.
That is the first question I want an athlete to answer before choosing an interval session: what are we trying to develop, and what should a good execution look like?
Start with the purpose
HIIT covers a wide range of demanding interval sessions. It is not a single intensity and it does not always mean sprinting. For an orienteer, the target might be sustained aerobic work, running fast on uneven ground or maintaining a technical process at competition intensity. Those purposes can overlap, but they should not be left implicit.
Buchheit and Laursen’s reviews explain how the work duration, effort, recovery, number of repetitions and exercise mode all influence the training stimulus. Similar cardiovascular demands can also come with different muscular and mechanical loads. That matters when the next day includes a forest session, strength training or a race.
Name the capacity or race demand you want to develop.
Choose repetitions, recovery and terrain that support that purpose.
Check whether effort, movement and technical execution remain appropriate.
Use the response to decide the next step.
Three examples, three different jobs
These are coaching examples to adapt to the athlete, rather than protocols claimed to be best for everyone. Each assumes an appropriate warm-up and a gradual introduction to this type of work.
| Purpose | Example | What I would look for |
|---|---|---|
| Sustained aerobic work | 4 × 4 minutes on runnable ground, with 3 minutes of easy recovery | A hard but controlled effort, with repeatable output and no sprint start |
| Shorter aerobic intervals | 2 sets of 6 × 45 seconds, with 30 seconds easy between repetitions and 3 minutes between sets | Smooth running and enough control to keep the later repetitions purposeful |
| Navigation at speed | 6 short courses of roughly 2–3 minutes, with enough recovery to review and prepare | An independent plan, accurate direction and reliable control approaches as speed rises |
The numbers are adjustable. An athlete returning to harder work may need fewer repetitions. A technically demanding map may require shorter courses or more recovery. Changing the format is useful when it helps deliver the intended work.
What does “hard” mean here?
“95% effort” is too ambiguous on its own. It could be interpreted as a percentage of maximum heart rate, a percentage of maximal sprint speed or a subjective feeling. Those are different measures.
Use a shared intensity system and combine it with breathing, perceived effort and the quality of movement. Heart rate is helpful, but it responds with a delay during short repetitions. Running faster to force it into a zone can distort the session. In forest terrain, the same effort also produces very different speeds on a path, a climb and soft ground.
Add technical pressure deliberately
A harder course is not automatically a better HIIT session. If repeated relocations interrupt the work, the physical stimulus and the technical task may both become unclear.
Decide which demand has priority. For predominantly physical work, choose terrain and navigation that allow the effort to continue. For competition-specific practice, accept the variable rhythm and analyse what happens to the technical process. You can also alternate short runnable intervals with technically demanding ones, provided the reason is clear.
When direction breaks down repeatedly, ask whether the plan was weak, the pace exceeded the athlete’s current technical capacity or fatigue changed the execution. Those diagnoses lead to different adjustments.
Fit the session into the week
Count the other demanding work around it. A race, a fast relay simulation and a strength session all contribute load, even if only one is labelled “intervals”.
I would rather see one well-executed session that the athlete can absorb than add another because a weekly template has an empty slot. Progress one main variable at a time, such as the number of repetitions or the technical demand, so that the response remains understandable.
Afterwards, record more than completion: how the effort developed, whether the final repetitions resembled the first and what happened to navigation. The useful result is a stimulus you can explain and a next session you can choose with better information.
Sources and further reading
- Buchheit, M., & Laursen, P. B. (2013). High-intensity interval training, solutions to the programming puzzle: Part I: cardiopulmonary emphasis. Sports Medicine.
- Buchheit, M., & Laursen, P. B. (2013). High-intensity interval training, solutions to the programming puzzle. Part II: anaerobic energy, neuromuscular load and practical applications. Sports Medicine.
The session examples above are practical coaching applications. They are not presented as the protocols tested in those reviews.