# A single HIIT session does not alter blood sphingolipid levels in healthy young adults: The SphingoHIIT randomized controlled trial

PMID: 40687993
Journal: Computational and Structural Biotechnology Journal
Published: 2025
Authors: Angst T, Weber N, Fischer S, Lehmann J, Infanger D, Teav T, Schwendinger F, Streese L, Hinrichs T, Croci I, Schmied C, Gallart-Ayala H, Höchsmann C, Koehler K, Hanssen H, Schmidt-Trucksäss A, Ivanisevic J, Carrard J

## Question

Does a single 4x4-minute HIIT session acutely alter circulating blood sphingolipid levels in healthy young adults compared with physical rest?

## Summary

This tightly controlled randomized trial compared one supervised 4x4-minute cycling HIIT session with 30 minutes of seated rest in 36 healthy young adults. Despite repeated dried-blood-spot sampling and adjustment for key confounders, HIIT did not significantly change any measured sphingolipid species compared with rest.

## Population

- Healthy young adults aged 20-29 years from the Basel area
- Sample size: 36
- Age: Control 24.1 +/- 2.6 years; HIIT 24.7 +/- 2.0 years
- Sex: 50% female in each group
- Fitness level: Healthy and physically active, average VO2peak about 50 ml/kg/min
- Health status: Healthy adults without reported contraindications after screening

## Methodology

- Parallel randomized controlled trial
- Single intervention day within an 11-day controlled protocol
- University laboratory with home dried-blood-spot sampling
- Randomized and controlled study design.

## Protocol

- Single 4x4 cycling HIIT.
- Modality: Cycle ergometer.
- Work intervals: 4 minutes.
- Recovery: 3 minutes active recovery at RPE 11-13.
- Sets or repetitions: 4 intervals.
- Intensity: 85-95% maximal heart rate.
- Session duration: 30 minutes.
- Frequency: Single session.
- Program length: Acute intervention day.
- Progression: None.
- Physical rest.
- Modality: Seated rest.
- Intensity: Physical rest.
- Session duration: 30 minutes.
- Frequency: Single session.
- Program length: Acute intervention day.
- Progression: None.

## Outcomes

### CERT ceramides
Status: no clear change
HIIT did not significantly alter the four ceramides included in CERT1/CERT2 versus rest.

Adjusted linear mixed models found no significant group differences at post-intervention time points.

### Sphingolipid panel
Status: no clear change
No measured sphingolipid species differed significantly between HIIT and rest after the intervention.

47 species measured; no significant differences at 2, 15, 30, 60 minutes, or 24 hours after adjustment.

### Safety
Status: no clear change
No important harms or unintended effects were reported.

Descriptive safety reporting.

## Practical Insights

- A single 4x4 HIIT session did not acutely move the measured sphingolipid biomarkers in healthy active young adults.
- This is useful biomarker context but not evidence that HIIT lacks cardiometabolic training benefits.
- The 4x4 structure is reproducible but was delivered with screening, CPET, and supervision.

## Limitations

- Healthy active young adults only.
- Acute single-session design.
- Self-collected blood spots without supervision.
- Possible unmeasured changes between 60 minutes and 24 hours.
- Generalizability to older, lower-fitness, or clinical populations is limited.

## Safety And Adherence

- No important harms or unintended effects were reported.
- Participants were screened with resting ECG and CPET.
- HIIT was supervised by exercise physiologists.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/40687993/) (pubmed)
- [DOI](https://doi.org/10.1016/j.csbj.2025.07.004) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12274307/) (full text)

## Agent Guidance

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