High-Intensity Interval Training Improves Inhibitory Control and Working Memory in Healthy Young Adults
Question
Does a single bout of cycling HIIT improve inhibitory control and working memory more than moderate interval exercise, moderate continuous exercise, or rest in healthy young adults?
Summary
In a randomized crossover lab study, 25 healthy college students completed single sessions of HIIT, moderate-intensity interval exercise, moderate continuous exercise, and rest. After an 8-minute recovery, the HIIT session produced faster Stroop response times and more correct 2-back responses than several comparator sessions. This supports a short-term cognitive effect of acute cycling HIIT in healthy young adults, but it does not show long-term cognitive training effects.
Methodology
- Healthy college students with exercise experience.
- 25 participants.
- Cycle ergometer.
- Work intervals: 3 minutes at 90% HRmax.
- Recovery: 2 minutes at 70% HRmax.
- Intensity: Work at 90% HRmax; recovery at 70% HRmax.
- 15 minutes cycling plus 2-minute warm-up and 8-minute post-exercise rest before cognitive testing.
- Single acute session.
- Single session in crossover protocol.
- Randomized within-subject crossover acute experiment
- Inhibitory control, Working memory, and Exercise manipulation were tracked.
Outcomes
Exercise manipulation
HR and RPE were highest in HIIT, confirming intensity separation from comparators.
Stroop response time
HIIT improved Stroop response times versus selected comparator conditions.
Congruent HIIT vs CON p=.004; incongruent HIIT vs MICT p=.049 and vs CON p=.023; neutral HIIT vs MIIT p=.029 and vs CON p=.012.
Stroop accuracy
Stroop accuracy did not show a significant session effect.
Session p=.445; interaction p=.321.
2-back hits
HIIT increased correct 2-back responses compared with MIIT, MICT, and rest.
HIIT vs MIIT p=.041; vs MICT p=.02; vs CON p=.006.
Other 2-back metrics
Misses, false alarms, correction rejections, and response times did not differ between sessions.
All p>.05.
Insights
- A short acute HIIT bout may temporarily benefit executive-function task performance after a brief recovery.
- This evidence supports optional cognitive/alertness framing for acute sessions, but not claims of durable cognitive improvement.
- The protocol used cycle ergometry and HR targets, so app translation should use caution for bodyweight HIIT.
Limitations
- Acute single-session design.
- Small sample of healthy young adults.
- Cognitive accuracy was mostly insensitive to session effects.
- No biochemical measures to test proposed mechanisms.
- Long-term HIIT effects were not studied.
Safety
- Two recruited male participants dropped out because previous injuries required surgery; this was not described as caused by the study sessions.
- The authors stated HIIT was well tolerated.
- No intervention adverse events were reported in the the paper.