# Sprint Interval Training and Continuous Aerobic Exercise Training Have Similar Effects on Exercise Motivation and Affective Responses to Exercise in Patients With Major Depressive Disorders: A Randomized Controlled Trial

PMID: 30622487
Journal: Frontiers in psychiatry
Published: 2018
Authors: Gerber M, Minghetti A, Beck J, Zahner L, Donath L

## Question

Does sprint interval training affect exercise motivation, affective responses, fitness, physical activity, and depressive symptoms differently than continuous aerobic training in patients with major depressive disorder?

## Summary

In inpatients with major depressive disorder, 4 weeks of supervised cycling sprint intervals produced similar improvements in exercise motivation, affect during sessions, fitness, perceived fitness, and depressive symptoms compared with calorically matched continuous cycling. The study reported no serious adverse events, which matters because the population was clinically vulnerable and mostly inactive.

## Population

- Adults with unipolar major depressive disorder receiving inpatient treatment
- Sample size: 50
- Age: 36.4 +/- 11.3 years
- Sex: 39 women, 11 men
- Fitness level: Largely physically inactive
- Health status: Moderate to severe unipolar depression; major somatic comorbidities excluded

## Methodology

- Two-arm randomized controlled trial
- 4 weeks
- Inpatient psychiatric clinic with supervised bicycle ergometer exercise
- Randomized and controlled study design.

## Protocol

- Sprint interval cycling.
- Modality: Bicycle ergometer.
- Work intervals: 30 seconds.
- Recovery: 30 seconds complete rest.
- Sets or repetitions: 25 intervals.
- Intensity: 80% VO2max.
- Session duration: 35 minutes including warm-up/cool-down.
- Frequency: 3 times/week.
- Program length: 4 weeks.
- Progression: No detailed progression; intensity individualized from VO2max.
- Continuous aerobic cycling.
- Modality: Bicycle ergometer.
- Sets or repetitions: 20 minutes continuous cycling.
- Intensity: 60% VO2max.
- Session duration: 35 minutes including warm-up/cool-down.
- Frequency: 3 times/week.
- Program length: 4 weeks.
- Progression: No detailed progression; intensity individualized from VO2max.

## Outcomes

### Motivation
Status: no clear change
SIT and CAT did not differ in changes in self-determined exercise motivation.

Time-by-group effects not significant for motivation indices.

### Affect
Status: no clear change
SIT and CAT produced similar positive affective responses during and after sessions.

### Fitness and symptoms
Status: improved
Cardiorespiratory fitness, perceived fitness, physical activity, and depressive symptoms improved over time in both groups.

Between-group differences mostly not significant; CAT had larger self-reported physical activity increases.

## Practical Insights

- A structured SIT option may not undermine motivation or affect when carefully supervised in a clinical setting.
- Choice between interval and continuous formats may be valuable for adherence-sensitive populations.
- Affective-response tracking can be useful in app design for hard intervals.

## Limitations

- Short 4-week intervention
- Inpatient clinical context with usual treatment continuing
- Strict exclusions limit generalizability
- No long-term adherence follow-up

## Safety And Adherence

- During the entire study period, no serious adverse events occurred.
- The study excluded participants with several major somatic and psychiatric comorbidities.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/30622487/) (pubmed)
- [DOI](https://doi.org/10.3389/fpsyt.2018.00694) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6308196/) (full text)

## Agent Guidance

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