Barefoot running on grass as a potential treatment for plantar fasciitis: a prospective study

Key points

1. 0119 out of 20 participants improved pain scores by week 6, with a mean reduction of 38.8%
2. 02By 12 weeks, median pain reduction reached 58.3% from baseline
3. 03Pain was statistically lower at week 6 (2.5 vs 3.9 on NRS, p < 0.001) and week 12 (p = 0.002)
4. 04Participants ran 15 minutes every other day on grass at low intensity (RPE 11), meaning they kept running throughout treatment
5. 0518 of 20 participants said they would recommend the intervention to others

How it was conducted

Design

Prospective case series, no control group

Participants

20 recreational runners (10 male, 10 female) aged 34-65 years (mean 48) with confirmed plantar fasciitis; 28 initially enrolled

Intervention

15 minutes of barefoot running on grass every other day (RPE 11) for 6 weeks (21 sessions target)

Primary outcome

Morning pain score via Numeric Rating Scale (NRS) and Visual Analogue Scale (VAS) daily for 6 weeks and at 12-week follow-up

Compliance

76.2% overall (mean 16.1 of 21 sessions); 88.9% compliance to 3 sessions per week

Duration of prior symptoms

3 to 48 months (median 7.5 months)

What they found

• Pain at week 6: mean 2.5 +/- 1.4 vs baseline 3.9 +/- 1.4, p < 0.001
• Pain at week 12: median 1.5 (IQR 1.8), p = 0.002 vs baseline
• 19 out of 20 participants improved at week 6; mean % change in pain score -38.8 +/- 21.5%
• 18 out of 20 participants improved at week 12; median % change in pain score -58.3 (IQR 34.8)%
• Week-6 mean change: -38.8%, 95% CI -28.7% to -48.8%, range -85.4% to 3.7%
• Week-12 median change: -58.3%, 95% CI -40.0% to -96%, range -100% to 96%
• Statistically significant pain reduction first appeared at week 5 (p = 0.003) and was maintained through week 6 (p < 0.001) and week 12 (p = 0.002)
• 12 of 20 participants were running at least 5 km twice weekly in shoes on road at the 12-week point

Limitations

• No control group, so natural recovery over time cannot be excluded as an explanation for improvement
• No blinding of participants or investigators, introducing performance and detection bias
• Time spent barefoot during other daily activities was not recorded and could confound results
• Study commenced during spring 2020 in unusually dry weather in Ireland, meaning ground was firmer than ideal, which may have slowed early response

Why it matters

For patients

Recreational runners with plantar fasciitis may find that a simple low-cost programme of 15-minute barefoot grass runs every other day reduces pain while allowing them to keep running.

For clinicians

This case series provides early-stage evidence to consider barefoot grass running as an adjunct or alternative for plantar fasciitis patients who have not responded to conventional treatment, though a controlled trial is needed before firm recommendations can be made.

For readers

Results are promising but come from a small uncontrolled case series; a randomised trial comparing barefoot grass running to standard physiotherapy is needed to confirm efficacy.