# Effects of High-Intensity Interval Training on Executive Functions in College Students: Evidence from Different Doses

PMID: 37190536
Journal: Brain sciences
Published: 2023 Mar 29
Authors: Wang X, Liu Z, Zhang H, Ji C

## Question

Do low-dose and moderate-dose HIIT improve inhibition, cognitive flexibility, and working memory in college students, and does twice-weekly HIIT outperform once-weekly HIIT?

## Summary

College students randomized to one or two weekly 10-minute recumbent-bike HIIT sessions for six weeks improved executive-function test performance more than a no-HIIT control group. Two weekly sessions generally produced larger benefits than one weekly session, but executive-function scores trended downward after HIIT stopped.

## Population

- Healthy undergraduate college students
- Sample size: 81
- Age: Group means about 21.98-22.79 years
- Sex: Mixed; table totals 49 male/32 female
- Fitness level: Baseline VO2max about 36.95-39.46 mL/kg/min
- Health status: Physically and psychologically healthy

## Methodology

- Randomized controlled dose-comparison intervention
- 6-week intervention plus 6-week post-intervention follow-up
- University laboratory with recumbent-bike HIIT and executive-function testing
- Randomized and controlled study design.

## Protocol

- Moderate-dose bike HIIT.
- Modality: Recumbent bike.
- Work intervals: 60 s riding as quickly as possible.
- Recovery: 60 s slow riding.
- Sets or repetitions: 5 cycles.
- Intensity: Fast/maximal effort monitored by RPE and HR.
- Session duration: 20 min including 5-min warm-up and 5-min relaxation.
- Frequency: 2 sessions/week.
- Program length: 6 weeks.
- Low-dose HIIT and no-HIIT control.
- Modality: Recumbent bike for low-dose; normal living for control.
- Work intervals: Low-dose used the same 60 s fast intervals.
- Recovery: 60 s slow riding.
- Sets or repetitions: 5 cycles.
- Intensity: Fast/maximal effort monitored by RPE and HR.
- Session duration: 20 min for low-dose sessions.
- Frequency: Low dose 1 session/week; control none.
- Program length: 6 weeks.

## Outcomes

### Inhibition
Status: mixed
Inhibition reaction time improved with HIIT, while inhibition accuracy was not significantly affected.

Reaction time group x time F(4,156)=75.49, p<0.001; Time 2 exercise-group improvement 3.97-8.24%, p<0.05.

### Cognitive flexibility
Status: improved
HIIT improved cognitive flexibility, with moderate dose generally better than low dose.

Accuracy improvement 6.66-7.32%, p<0.05; reaction time improvement 5.55-7.49%, p<0.05.

### Working memory
Status: improved
Working-memory accuracy and reaction time improved after HIIT, especially in the moderate-dose group.

Accuracy group x time F(4,156)=81.23, p<0.001; reaction time group x time F(4,156)=73.46, p<0.001.

### Follow-up
Status: mixed
Executive-function measures remained above baseline in some comparisons but trended downward after HIIT stopped.

Article conclusion reports downward trend at Time 3 after cessation.

### Attendance
Status: improved
Both exercise groups had high attendance.

Low-dose 94.50%; moderate-dose 94.33%.

## Practical Insights

- A very short 5 x 60/60 s bike format is a plausible low-dose cognitive-health exercise format for students.
- Benefits may require continued training rather than a short one-time block.

## Limitations

- Single college-student population
- Outside exercise behavior difficult to track
- Achieved intensity not reported
- Some group labels in the table appear inconsistent with the text

## Safety And Adherence

- No adverse events reported in extracted text.
- RPE and heart rate were monitored during HIIT.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/37190536/) (pubmed)
- [DOI](https://doi.org/10.3390/brainsci13040571) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10136687/) (full text)

## Agent Guidance

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