# Energy compensation after sprint- and high-intensity interval training

PMID: 29244836
Journal: PLOS ONE
Published: 2017
Authors: Schubert MM, Palumbo E, Seay RF, Spain KK, Clarke HE

## Question

How much do adults compensate for exercise energy expenditure after SIT or HIIT, and what behavioral or fitness changes are associated with compensation?

## Summary

This secondary analysis found large person-to-person variation in energy compensation after 4 weeks of cycling sprint or HIIT. People with low compensation tended to lose more fat and improve VO2max more, while high compensators had smaller fitness gains and gained fat mass despite similar reported food-intake changes.

## Population

- Healthy moderately active adults randomized to cycling SIT or HIIT.
- Sample size: 24
- Age: 18-50 years; mean 29.5 +/- 7.5
- Sex: 58% female
- Fitness level: Moderately active
- Health status: Healthy; mean BMI in overweight range

## Methodology

- Secondary analysis of a 4-week randomized interval-training study
- 4 weeks
- Laboratory cycling training study
- Randomized study design.

## Protocol

- Cycling SIT or HIIT.
- Modality: Cycle ergometer.
- Work intervals: SIT 20 s; HIIT 1 min.
- Recovery: SIT 2 min; HIIT 1 min.
- Sets or repetitions: SIT 3-5 sprints; HIIT 6-8 intervals.
- Intensity: SIT all-out at 5% bodyweight resistance; HIIT at 90% PPO.
- Session duration: 10-20 min depending on protocol and week.
- Frequency: 3 sessions/week.
- Program length: 4 weeks.
- Progression: Intervals increased over weeks.

## Outcomes

### Energy compensation
Status: mixed
Compensation ranged widely from large negative values to more than full compensation.

Mean compensation -346 +/- 634%; range -2081% to +805%.

### Fat mass
Status: mixed
Low compensators lost fat mass, while high compensators gained fat mass.

-1.41 kg vs +0.33 kg; p<0.0001.

### VO2max
Status: improved
Low compensators had larger VO2max gains than high compensators.

+2.10 vs +0.41 mL/kg/min; p=0.008.

### NEPA
Status: mixed
Change in non-exercise physical activity was a strong predictor of compensation.

Final model R2=0.63; NEPA added R2=0.32, p=0.001.

## Practical Insights

- User energy compensation can overwhelm expected fat-loss effects from interval training.
- Maintaining daily activity after HIIT may be as important as the workout itself.
- Short HIIT programs should not promise predictable weight loss.

## Limitations

- Small sample
- No non-exercise control group in this analysis
- Self-reported diet records
- Exercise energy expenditure estimated rather than directly measured
- Short 4-week duration

## Safety And Adherence

- The secondary analysis did not report adverse events.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/29244836/) (pubmed)
- [DOI](https://doi.org/10.1371/journal.pone.0189590) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5731706/) (full text)

## Agent Guidance

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