# Effects of 6-week sprint interval training compared to traditional training on the running performance of distance runners: a randomized controlled trail

PMID: 39981302
Journal: Frontiers in Physiology
Published: 2025-02-06
Authors: Jin K, Cai M, Zhang Y, Wu B, Yang Y

## Question

Does a 6-week field SIT program improve aerobic capacity and running performance more than traditional long-distance training in well-trained male distance runners?

## Summary

In 20 well-trained male distance runners, 6 weeks of twice-weekly field sprint interval training improved time to exhaustion and 100 m, 400 m, and 3000 m times within the SIT group. Compared with traditional endurance training, SIT was clearly better only for 3000 m time; VO2max, oxygen cost, TTE, 100 m, and 400 m between-group differences were not statistically significant.

## Population

- Twenty well-trained young male distance runners.
- Sample size: 20
- Age: IT 19 +/- 1 years; CT 20 +/- 1 years
- Sex: Men
- Fitness level: Well-trained distance runners with mean VO2max 67.4 +/- 4.5 mL/kg/min
- Health status: Apparently healthy athletes

## Methodology

- Randomized controlled trial
- 6 weeks
- Field running training plus laboratory treadmill testing
- Randomized and controlled study design.

## Protocol

- Field running SIT.
- Modality: Sprint running.
- Work intervals: 30 s maximal sprint.
- Recovery: 3.5 min recovery until HR below 70% HRmax.
- Sets or repetitions: 10.
- Intensity: Maximal; approximately 175% MAS average interval intensity.
- Session duration: 50 min including 3 min cooldown.
- Frequency: 2 sessions/week.
- Program length: 6 weeks.
- Progression: No formal progression reported; interval intensity declined within sessions.
- Traditional endurance training.
- Modality: Distance and interval running.
- Work intervals: Varied: 10 km; 3000 m, 2000 m, 1500 m, 1000 m, and 400 m repeats.
- Sets or repetitions: Each of six programs conducted twice across 12 sessions.
- Intensity: 70%-85% HRmax.
- Frequency: 2 sessions/week.
- Program length: 6 weeks.
- Progression: Varied traditional endurance programs.

## Outcomes

### TTE
Status: improved
The SIT group improved time to exhaustion within group, while the control group did not.

IT 8.30 +/- 0.22 to 8.42 +/- 0.18, p<0.01; between-group post difference p=0.102.

### 3000 m
Status: improved
SIT improved 3000 m time and was superior to control after training.

IT 527.48 +/- 4.44 to 522.61 +/- 3.52 s, p<0.01; between-group p<0.01, d=1.53.

### VO2max
Status: no clear change
VO2max did not significantly improve within the SIT group and did not differ significantly between groups.

IT p=0.055; between-group post p=0.353, d=0.43.

### Oxygen cost
Status: no clear change
Oxygen cost trended lower in SIT but was not statistically significant.

IT p=0.077; between-group post p=0.162, d=0.65.

## Practical Insights

- For trained runners, field SIT can be programmed without treadmills or cycle ergometers.
- The clearest comparative benefit was 3000 m performance rather than VO2max.
- Long recovery intervals may help preserve repeated maximal sprint quality.

## Limitations

- Small sample size.
- Men only and narrow young adult age range.
- Short 6-week intervention.
- Baseline training history and trainability were not deeply characterized.
- No detailed adverse-event reporting.

## Safety And Adherence

- Adverse events and injuries were not reported.
- Potential risks were explained and participants gave written informed consent.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/39981302/) (pubmed)
- [DOI](https://doi.org/10.3389/fphys.2025.1536287) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11839621/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.