HIIT
HIIT is a training format that alternates very hard work bouts (often 15–60 seconds) with recovery periods. The goal is dense cardio and metabolic stimulus in a short session — not a replacement for progressive strength programming.
Definition
HIIT (High-Intensity Interval Training) alternates short high-effort intervals with recovery (full rest or easy work). Density is high: a lot of useful work in little time.
💡 HIIT is not “cardio until you collapse.” It is a prescription of intensity and work:rest ratios, scalable per client.
Why coaches use it
- Time-efficient conditioning
- Improves anaerobic capacity and repeat-effort tolerance
- Easy to adapt across modalities
- Pairs well with RPE on work bouts
Typical structure
| Element | Common range |
|---|---|
| Work | 15–60 seconds |
| Recovery | 1:1 to 1:3 work:rest |
| Total time | 10–25 minutes |
| Work RPE | 8–10 |
| Frequency | 1–3× / week |
Simple example (12 min)
- Warm-up 5–8 min
- 8 rounds: 30 s hard / 60 s easy
- Cool-down 3–5 min
Common mistakes
- ❌ HIIT every day “to burn more”
- ❌ Technique collapsing by round 3
- ❌ Replacing all strength work with HIIT
- ❌ Skipping warm-up before near-max intervals
HIIT vs other formats
- vs LISS / zone 2: higher density and fatigue, less easy aerobic volume
- vs Tabata: Tabata is a specific HIIT protocol (20/10 × 8)
- vs circuit training: circuits can stay submax; HIIT targets near-relative max efforts
Takeaway
HIIT is a conditioning density tool. Program it when goals and recovery allow — not as a religion.
Common questions
What is HIIT?
HIIT (High-Intensity Interval Training) alternates short hard efforts with recovery (rest or easy work). Sessions often last 10–25 minutes excluding warm-up.
HIIT or LISS — which should I use?
Use HIIT to densify conditioning when time is limited and recovery allows. Use LISS / zone 2 for aerobic base at lower fatigue cost. They complement each other.
How many HIIT sessions per week?
Usually 1–3 depending on lifting volume and sleep. More often raises neural fatigue and can hurt heavy strength work.
Related terms
LISS (Low-Intensity Steady State) is continuous easy cardio at a conversational pace — useful for recovery, aerobic base and extra calorie burn.
Zone 2 is a moderate aerobic intensity (often ~60–70% HRmax) where you can talk in full sentences — foundation of endurance base.
Tabata is a 4-minute HIIT protocol: 20 seconds max effort, 10 seconds rest, 8 rounds. Maximum efficiency in minimum time.
Circuit training chains several exercises with little rest. Ideal for burning calories and improving cardiovascular fitness while keeping muscle.
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