Categories / HIIT & conditioning
Sprint Interval Training
All-out 20-30 second sprints, few repeats.
How to start
After a 10-minute warm-up, do 4 sprints of 20 to 30 seconds at a hard effort (on a bike, rower or hill) with 3 to 4 minutes easy between. Do it once or twice a week.
How to progress
Add one sprint every couple of weeks up to 6 to 8. Keep rest long enough to recover.
What the evidence says
Evidence: moderate
A 2026 pooled analysis of 40 trials (1,460 people) found that sprint interval training improved insulin resistance and LDL cholesterol compared with no exercise, and gave broadly similar results to steady moderate exercise. The authors rated the certainty of the evidence as low to very low. A 2026 review of 25 studies in adults aged 60 and over found HIIT improved fitness (VO2peak), though it did not show that it beats steady exercise, and reporting of side effects was inconsistent.
Take care: Sprinting loads muscles and tendons: warm up very well. Not for anyone with heart disease or uncontrolled blood pressure. Cycling or rowing is gentler than running.
Sources
12-week starter plan
One or two sessions a week of very hard efforts, with plenty of recovery between.
Tick each week as you finish it; your ticks are saved on this device only. Repeat a week if it felt hard. Weeks 4, 8 and 12 hold steady so you can settle. This is a general plan, not medical advice.
Add reminders to your calendar
Pick your days and time. You will download a calendar file that adds 12 weeks of reminders to Google, Apple or Outlook calendar.
Calories and weekly minutes
Enter your details for a rough estimate. Based on about 8.5 METs (Typical effort for this activity (estimated)). Real figures vary by 20% or more between people.
Tips and common mistakes
Tips
- Choose a bike or hill to reduce impact.
- Warm up thoroughly.
- Rest fully between sprints.
Common mistakes
- Sprinting cold.
- Too many sessions.
- Cutting rest short.
Kit and cost
Low to moderate Approximate UK prices.
- A bike, rower or hill
- A timer
- Supportive shoes
Frequently asked questions
Is sprint training worth it?
The pooled analysis found improved insulin resistance and LDL cholesterol compared with no exercise, but certainty was low.
How long is a sprint?
Usually 20 to 30 seconds, all-out.
Is it safe?
It is very demanding. Check with a GP first if you have a health condition.
Good for: Heart & fitness Weight loss
Compare with similar options
| Sprint Interval Training | HIIT | Tabata | Norwegian 4x4 | |
|---|---|---|---|---|
| Typical session | 15 min × 3/wk | 25 min × 3/wk | 4 min × 4/wk | 40 min × 2/wk |
| Effort | ●●●●● | ●●●●● | ●●●●● | ●●●●● |
| Cost | Low cost | Free | Free | Low cost |
| Equipment | Some equipment | No equipment | No equipment | Basic kit |
| Impact | Medium impact | Medium impact | Medium impact | Medium impact |
| Fitness needed | Moderate fitness | Some fitness | Moderate fitness | Moderate fitness |
| Evidence | moderate | moderate | limited | limited |