# #MindinBody - feasibility of vigorous exercise (Bikram yoga versus high intensity interval training) to improve persistent pain in women with a history of trauma: a pilot randomized control trial

PMID: 31464643
Journal: BMC Complementary and Alternative Medicine
Published: 2019 Aug 29
Authors: Flehr A, Barton C, Coles J, Gibson SJ, Lambert GW, Lambert EA, Dhar AK, Dixon JB

## Question

Is vigorous exercise feasible for women with persistent pain and trauma history, and do Bikram yoga and HIIT differ on pain, psychological, functional, and autonomic outcomes?

## Summary

This pilot randomized trial compared 8 weeks of Bikram yoga with a gym-based high-intensity interval training class in women with persistent pain and trauma history. Pain severity and interference improved over time across both groups, but there was no between-group difference for the primary pain outcome. Bikram yoga showed better physical functioning, mental health, and HRV signals than HIIT. The HIIT comparator was feasible for some participants but had lower completion and was not precisely intensity-quantified.

## Population

- Thirty-two women with persistent pain and a history of trauma randomized to Bikram yoga or HIIT.
- Sample size: 32
- Age: Mean 30.2 years; range 21-47 years.
- Sex: Women only.
- Health status: Persistent pain for more than 12 months and trauma history; BMI mean 26.9 kg/m2.

## Methodology

- Open-label pilot parallel randomized controlled trial comparing Bikram yoga with an active HIIT comparator.
- 8-week intervention with baseline and post-intervention assessment.
- Community and commercial exercise settings in Melbourne, Australia.
- Randomized and controlled study design.

## Protocol

- Commercial functional HIIT class.
- Modality: Functional small-group HIIT.
- Work intervals: Varied by class format; not fully reported.
- Recovery: Varied by class format; not fully reported.
- Sets or repetitions: 45 min class with Teach It, Do It, and Beat It sections.
- Intensity: High intensity, scaled individually; objective target not reported.
- Session duration: 45 min.
- Frequency: 3 sessions/week prescribed.
- Program length: 8 weeks.
- Progression: Exercises scaled to individual ability; no formal progression reported.
- Bikram yoga.
- Modality: Heated yoga.
- Recovery: Rest and modifications as needed.
- Sets or repetitions: 26 postures.
- Intensity: Vigorous heated yoga.
- Session duration: 90 min.
- Frequency: 3 sessions/week prescribed.
- Program length: 8 weeks.

## Outcomes

### Primary pain outcome
Status: no clear change
There was no between-group difference between Bikram yoga and HIIT on BPI total pain severity/interference.

ANCOVA F(1,29)=0.01, p=0.914.

### Pain over time
Status: improved
Pain severity/interference decreased from baseline to 8 weeks across groups.

BPI total 7.94 +/- 3.63 at baseline to 6.75 +/- 3.98 at 8 weeks; F(1,31)=6.29, p=0.018.

### Secondary quality-of-life and HRV outcomes
Status: mixed
Bikram yoga outperformed HIIT for physical functioning, mental health, and SDNN HRV signals, while most other secondary outcomes did not clearly differ.

SF-36 physical functioning p=0.019; mental health p=0.005; SDNN HRV favored Bikram yoga in reported analyses.

### Feasibility
Status: mixed
Overall retention was high, but HIIT had lower post-assessment completion and lower average attendance than Bikram yoga.

Completion: Bikram yoga 17/17; HIIT 12/15. Attendance: 1.4 vs 1.2 classes/week.

### Safety
Status: mixed
No injuries were reported, but some participants stopped attending because the intervention was too intense.

Three women (about 9% of the total sample) stopped attending due to intensity.

## Practical Insights

- For users with persistent pain or trauma history, a HIIT class must be easy to start, carefully scaled, and medically screened.
- Track both non-starts and dropouts; complicated enrollment can undermine feasibility before exercise begins.
- This paper should not be used to claim HIIT improves pain, because the active comparator design found no HIIT advantage and lacked a non-exercise control.

## Limitations

- Small pilot sample.
- All participants were women with persistent pain and trauma history.
- HIIT protocol was a commercial class with limited objective intensity detail.
- No waitlist or usual-care control group.
- No long-term follow-up.

## Safety And Adherence

- No injuries were reported.
- Three women stopped attending because the intervention was too intense.
- Medical clearance and psychiatric screening were required.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/31464643/) (pubmed)
- [DOI](https://doi.org/10.1186/s12906-019-2642-1) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6714085/) (full text)

## Agent Guidance

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