# Physiological and Performance Impacts After Field Supramaximal High-Intensity Interval Training With Different Work-Recovery Duration

PMID: 33162893
Journal: Frontiers in Physiology
Published: 2020-10-08
Authors: Brandão LHA, Chagas TPN, Vasconcelos ABS, de Oliveira VC, Fortes LS, de Almeida MB, Mendes Netto RS, Del-Vecchio FB, Neto EP, Chaves LMS, Jimenez-Pavón D, Da Silva-Grigoletto ME

## Question

Do 15 s versus 30 s supramaximal running intervals with equal passive recovery produce different acute performance, metabolic, and muscle-damage responses?

## Summary

In 15 recreational male runners, acute supramaximal field-running intervals using 15 s or 30 s work with equal passive rest produced similar distance/time and similar lactate and muscle-damage marker responses overall. The 15 s format allowed more repeated bouts, and the authors suggested it may need longer recovery because of more accelerations and decelerations.

## Population

- Healthy recreational male runners.
- Sample size: 15
- Age: 28.0 +/- 8.0 years
- Sex: Men
- Fitness level: Recreational runners
- Health status: Apparently healthy

## Methodology

- Randomized counterbalanced crossover acute field study
- Two acute HIIT sessions separated by 72 h to 7 days
- Official outdoor running track
- Randomized and controlled study design.

## Protocol

- H15 supramaximal running.
- Modality: Track running.
- Work intervals: 15 s.
- Recovery: 15 s passive rest.
- Sets or repetitions: One set until exhaustion.
- Intensity: 130% vVO2max.
- Session duration: Variable until exhaustion after 5 min warm-up.
- Frequency: Acute session.
- Program length: Single trial.
- Progression: None.
- H30 supramaximal running.
- Modality: Track running.
- Work intervals: 30 s.
- Recovery: 30 s passive rest.
- Sets or repetitions: One set until exhaustion.
- Intensity: 130% vVO2max.
- Session duration: Variable until exhaustion after 5 min warm-up.
- Frequency: Acute session.
- Program length: Single trial.
- Progression: None.

## Outcomes

### Bout count
Status: improved
H15 allowed more repeated bouts than H30.

p=0.001; effect size=1.19.

### Distance/time
Status: no clear change
Total distance and stimulus time were similar between H15 and H30.

### Blood lactate
Status: mixed
Lactate increased after both sessions, with no clear between-condition difference.

H30 decreased from 5 to 10 min post, p=0.004.

### CK/LDH
Status: worse/safety concern
Both formats increased CK and LDH at 24 h, indicating acute muscle stress.

CK increased pre to 24 h in H15 p<0.001 and H30 p=0.001; LDH increased in both.

## Practical Insights

- At the same 1:1 work:rest ratio and supramaximal target, shorter running intervals increase repetitions and transitions.
- Track-based supramaximal intervals need clear termination criteria.

## Limitations

- Small sample
- Acute-only design
- Male recreational runners only
- Surrogate recovery biomarkers
- No DOMS visual analog scale

## Safety And Adherence

- No adverse events or injuries were reported.
- Participants were excluded for relevant health/discomfort criteria and trials had stop rules.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/33162893/) (pubmed)
- [DOI](https://doi.org/10.3389/fphys.2020.01075) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7580678/) (full text)

## Agent Guidance

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