Effectiveness of short sprint interval training in women with major depressive disorder: a proof-of-concept study
Question
Does a 2-week short sprint interval training protocol improve depressive symptoms, physical fitness, body composition, and incidental physical activity in adult women with major depressive disorder?
Summary
This proof-of-concept randomized trial tested six very short sprint interval cycling sessions over 2 weeks in adult women with moderate or severe major depressive disorder. Compared with control, the sSIT group had significant reductions in HAM-D21 depressive symptom scores and improvements in maximum aerobic power, total test time, countermovement jump, body fat percentage, and pedometer-measured steps. The trial was very small, short, and limited to women with unipolar MDD, so findings need confirmation.
Methodology
- Adult women with moderate or severe major unipolar depressive disorder who completed follow-up.
- 17 participants.
- Cycle ergometer.
- Work intervals: 5 seconds all-out at maximum possible cadence.
- Recovery: 30-45 seconds active recovery at 50 W and about 60 rpm.
- Intensity: Sprint load equal to maximum aerobic power achieved during incremental test; all-out cadence.
- 6-10 minutes.
- 3 times per week with 24-48 hours rest between sessions.
- 2 weeks.
- Proof-of-concept randomized controlled trial with pre- and post-intervention assessments.
- Depressive symptoms, Maximum aerobic power, Total time in incremental test, and Countermovement jump were tracked.
Outcomes
HAM-D21 depressive symptoms
HAM-D21 scores decreased in the sSIT group and not in the control group.
sSIT pre 24.67 +/- 8.29, post 16.89 +/- 10.12, delta -34.30% +/- 32.26%; control pre 22.50 +/- 6.97, post 24.00 +/- 8.30, delta 5.46% +/- 24.66; group x time F=14.332, p=0.002; sSIT pre-post p<0.001.
Maximum aerobic power
Maximum aerobic power improved in the sSIT group compared with control.
sSIT 141 +/- 19 W to 155 +/- 21 W; control 119 +/- 16 W to 118 +/- 16 W; interaction p=0.016; delta p=0.015.
Total time in incremental test
Total incremental test time improved in sSIT and decreased slightly in control.
sSIT 569 +/- 75 s to 653 +/- 101 s; control 514 +/- 51 s to 505 +/- 46 s; interaction p<0.001; delta p=0.001.
Body fatness
Body fat percentage decreased in the sSIT group and increased in control.
sSIT 32.4% +/- 4.5 to 29.9% +/- 4.1; control 34.7% +/- 1.8 to 35.6% +/- 1.9; interaction p<0.001; delta p<0.001.
Steps
Four-day pedometer steps increased in sSIT and decreased in control.
sSIT 18,843 +/- 8,781 to 24,017 +/- 10,882; control 13,343 +/- 9,511 to 10,181 +/- 6,905; interaction p=0.009.
Handgrip strength and several anthropometric measures
Handgrip strength, body mass, BMI, waist circumference, and abdominal circumference did not show significant intervention effects.
Reported interaction p values were non-significant for these variables.
Insights
- Very short sprint intervals can be structured as 5 seconds hard with 30-45 seconds active recovery, keeping total session time near 6-10 minutes.
- Low-volume sprint training may be promising for populations where lack of time and low adherence are major barriers.
- Clinical sprint protocols need screening because all-out efforts and maximal testing were used.
- Exact replication requires a cycle ergometer and maximum aerobic power testing.
Limitations
- Energy intake was not controlled.
- Only unipolar MDD patients were included.
- Only women were studied.
- VO2max was not measured at follow-up because of metabolic cart technical issues.
- Maximum aerobic power and total test time were used as aerobic fitness indices instead of VO2max.
- Limited sample size.
- Short intervention and no longer follow-up.
Safety
- PAR-Q was used to identify risks and contraindications before maximal testing and high-intensity exercise.
- Participants with conditions preventing exhaustive test or exercise program participation were excluded.
- No adverse events were reported in the article text.