In 2025, Blisterhelp ran an internal blisterprevention pilot with 29 runners at the 39th Marathon des Sables (MDS Legendary). The aim was to see how a structured prevention and education package influenced blister patterns—particularly under the metatarsal heads (balls of the feet)—in a real desert multiday race.

Important note
This was an internal quality improvement / service style project, not an ethics committee–approved research study. The data are shared here for educational purposes and to explain how Blisterhelp’s prevention protocols and blister kits are evolving, rather than as formal research.

How this internal pilot was conducted

Participants and recruitment

  • Runners were recruited from the MDS 2025 start list via a UK MDS training Facebook group
  • Participation was voluntary; 29 runners completed the pilot from many different countries, not just the UK.

Prerace education

  • Group Zoom calls covering desert foot risks, foot preparation, footwear and sock choices, backpack weight, and blisterprevention strategies.
  • Written and zoom call guidance on how to use each component of the prevention and treatment kits.
  • Q&A support in the leadup to the race to individualise plans for each runner.

Prevention and treatment kit
Each runner was provided with:

  • Prevention items: Armaskin antiblister liner socks x 3, pre-race skinconditioning cream, Porontype pressure reducing insoles, frictionreducing inshoe engo patches, in- between the toe’s protection (e.g. alpaca wool). 
  • Customised treatment kit: Various sized island dressings for feet and other high shear stress areas, hypoallergenic fixation tape (e.g. Hypafixtype), KT pro tape, medical skin adhesive wipes intended to be used to secure K-tape, and dressings to sweaty skin. Disinfectant wipes for cleansing skin and wounds, antiseptic wipes for open wounds, medical gloves to help with treatment sterility. Blistershield powder for application onto dressing and tape, reducing additional friction, sterile scissors. All products designed to complement those found in the medical tent.

Onrace medical support

  • Access to the event medical tent and field checkpoints, for self-treatment and taping, dressing, blister drainage (where appropriate) and offloading of blisters by medical professionals.

Postrace followup

  • Online questionnaire after the race capturing: blister locations and severity, need for medical treatment, satisfaction with care, product use and perceived usefulness of pre-race education.

Key internal findings

Race completion

  • 100% of the 29 runners finished the race.

Overall blister incidence

  • 75.9% (22/29) reported at least one blister.
  • This is in line with published blister rates for desert multistage ultras, where 74–100% of runners often develop blisters.​

Metatarsal head (balloffoot) blisters

  • Incidence 6.9% (2/29 runners).
  • Both affected runners had small metatarsal blisters and completed the race with appropriate medical care.
  • In other desert events, research and race reports suggest balloffoot involvement is often around 12–20%, making it one of the commonest blister sites.​

Medical care and satisfaction

  • 55.2% (16/29) required blister treatment or foot care from the medical team.
  • Average treatment satisfaction was 4.4/5.0.
  • Overall satisfaction with taking part in the pilot was 96.6% (28/29).

How does this compare with other desert ultras?

Published work from similar hot, multiday events helps to put these numbers in context:

Al Andalus Ultimate Trail (Spain, 5day, 219 km)

  • 76% of runners developed blisters after four days.​
  • Around 16% of blisters were reported under the ball of the foot, making it a key problem area.​

RacingThePlanet 250 km desert series (e.g. Gobi, Sahara, Atacama)

  • Reports and webinars summarising multiple editions describe blister incidence between roughly 74% and 100%.​
  • Many runners develop most of their blisters by the end of the second day.

Other desert and hotroad ultras (e.g. Badwater 135)

  • Official guidance from Badwater and associated medical pieces highlight severe heel and forefoot blisters as common issues in nonstop desert road races, despite experienced crews and strong preparation.​

Taken together, these data suggest:

  • The overall blister rate in the Blisterhelp MDS pilot (75.9%) is consistent with what is seen in other desert multiday events.
  • The metatarsal head blister rate of 6.9% appears lower than the typical ~16–20% balloffoot involvement reported elsewhere, acknowledging differences in how sites and events are defined.​

Because this was an internal qualityimprovement project, these figures should be read as practicebased evidence that guides current protocols, not as definitive proof of superiority.

The role of the customised blister treatment kit

Prevention is only part of the story in a race as demanding as MDS. When blisters did occur—particularly under the metatarsal heads—the customised treatment kit allowed:

  • Early, controlled draining where appropriate, rather than allowing large, tense blisters to tear inside the shoe.
  • Immediate dressing and offloading using island dressings, and secure fixation tape suited to hot, sweaty skin, alongside sterile cleansing and antiseptic wipes stopped blisters progressing.
  • Better protection of blister roofs and wound beds, reducing the risk of wounds deepening or becoming contaminated over successive stages.​

This combination of prevention, education and treatment readiness is what allowed runners with even quite challenging blisters to continue and finish safely.

What this means for runners and medics

Even though this pilot is not formal research, it has practical implications:

For runners heading to desert ultras

  • A multistep approach (skin conditioning, anti-friction liner socks, insoles, friction reducing patches, taping strategy and a proper treatment kit) is more realistic than relying on a single “magic” product.​
  • Understanding how to use that kit—and when to ask for help—can be as important as the kit itself.

For medics and race organisers

  • Structured prerace education plus agreed treatment protocols can help keep blisters at the level of “manageable problem” instead of “reason to withdraw”.
  • Internal field data like this, transparently labelled, can be a useful bridge between published literature and daytoday race practice.

Blisterhelp will continue to use this kind of practicebased evidence, alongside published studies, to refine prevention kits, treatment approaches and educational content for future desertultra runners.

References (for interested readers and medics)

  1. Leal Junior ECP et al. The enemy of the feet: blisters in ultraendurance runners. Br J Sports Med. 2010;44(8):555–9.​
  2. Rushton R. Blisters in Ultramarathon (Southern Lakes Ultra webinar summary and desertultra blister statistics).​
  3. Badwater 135. Blister Care and Getting Your Feet to the Starting Line (official Badwater University guidance).​
  4. Contemporary reviews on friction blisters and desert foot problems summarised in recent podiatry and sports medicine literature.​

About The Author

I’m Lindsey Ebbs, a podiatrist with more than three decades of clinical experience and a passion for working in the world’s toughest endurance events.

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