Preventing and treating blisters from physical activity
Why blisters occur during exercise
Blisters are usually caused by friction that occurs during physical activity. This repeated rubbing separates the two outer skin layers, forming a pocket that fills with fluid. This fluid is usually clear or bloody but can also be white or yellowish – a sign of infection.1 During physical activity, the most common causes of friction are repetitive movement, shoes that don’t fit well, and socks that are rough or worn out.3
Particular areas of the body are more prone to blisters. These pressure points are more likely to be impacted by repetitive activity and contact with shoes, clothing or other equipment.2
Heat and moisture can also contribute to blister development. In hot conditions, the body produces more perspiration to try and cool us down. This extra moisture can soften the skin and make it vulnerable to injury – especially if contact is prolonged (think sweaty socks!).2
5 Ways to prevent blisters
1. Wear suitable shoes
- Wear shoes that fit you comfortably. If they’re too loose or too tight, they’ll cause friction as you move. Securely fitting shoes will help stop your foot slipping inside the shoe and reduce friction.2
- No matter how comfortable they felt in the shop, new shoes need to be “broken in”. Start by wearing them for short periods of time or smaller distances and increase these gradually.2
- Different activities create different forces on our bodies. Many shoes are designed to support specific types of activity, e.g. running, hiking, walking. Choosing shoes that suit your activity will ensure optimal support.2
- Take notice of any areas where your shoe causes extra pressure or friction, e.g. stitching or top edge of the heel. Sometimes, adjusting the laces or using a little padding is a suitable solution, but discomfort or irritation over a pressure point is a reason to consider other designs.2
Your choice of socks plays a critical role in blister prevention. Cotton socks, for example, tend to absorb moisture and may increase friction.3 Instead:
- Socks that absorb moisture will increase the risk of friction and blisters. Natural fibres are not always the best option – as cotton and bamboo absorb moisture. Choose socks made of materials that draw moisture away from your skin e.g. wool or some synthetics. Look for phrases such as “moisture wicking” on the packaging.3
- Some people find wearing two layers of socks is beneficial. Using a thin sock (or liner) under a thicker sock can improve moisture wicking and provide extra cushioning. Others find that two layers increases the slipping of the foot within the shoe or between layers and increase friction.3
- Wear socks that are the right size for you. If they’re too small, they may cause extra pressure on your feet and irritate the skin. Socks that are too big can wrinkle, which also increases pressure and irritation.3
- Replace socks showing signs of wear. If the material is thinning or losing elasticity, it may start to cause problems and should be retired. 3
3. Apply creams and powders
Chafing is another common skin concern that can be very painful, and severe cases can lead to the development of blisters. Many runners suffer from chaffing between the thighs and under the upper arms due to repetitive movements creating friction against other skin surfaces or clothing. This friction can be reduced or prevented by using specially designed products such as chafing cream. Medicated powders can also be helpful in minimising the impact of heat, moisture and friction. Traditional barrier creams may not be beneficial as they can be thick and sticky, thereby impeding frictionless movement. If skin is broken or raw, these creams may also trap moisture underneath and worsen the problem.3
4. Protect pressure points
Although friction blisters most commonly occur on the feet, it’s important to remember they can develop in any area. Avid gardeners may experience blistering on their palms from using secateurs, a baseball catcher might form blisters from the protective face mask, and hikers might have blisters around the collarbones or shoulders from a backpack. Protecting known and potential pressure points can save you from pain and disruption to your activities.2
There are many products that can provide extra padding and comfort for pressure points. Foam padding or podiatry felt can be cut to fit and provide protection when placed in shoes or on equipment.8 For a less bulky option, consider a hydrocolloid dressing – often referred to as a second skin.1
5. Love the skin you’re in!
The essential functions of skin are often unrecognised or understated. Society can be more focused on our skin’s appearance, but it helps hold us together and is a barrier against various environmental harms. Maintaining your skin’s health is worth investing a little time and money. Use pH neutral products to cleanse and moisturise your skin.1 Make sure you dry thoroughly (but gently) after washing, paying attention to trouble spots like in between toes. Apply sunscreen regularly when outdoors.2
Treating a blister safely at home
The main goals of treating a blister are managing pain, preventing infection, and restoring your skin’s integrity as quickly as possible. Firstly, assess the size and severity – is it intact or has it broken? How might it impact you daily activities? Do you have medical conditions that place you at higher risk of infection?
1. Intact blisters
Over time, your body will reabsorb the fluid contained in a blister. In most cases, it’s better not to break the skin to drain the fluid because doing so creates a portal for possible infection.1
Place a simple protective dressing over it – foam dressings are ideal as they provide cushioning and are less traumatic to remove.1
If the blister does rupture, the dressing will absorb the fluid, and the area will be protected from outside sources of infection.
Try to avoid the activity that caused the blister until it has healed.5
If the overlying skin is partially or completely removed (deroofed), follow the below guidance but omit steps 3-5.4
3. Draining a blister
If you must drain a blister:
- Wash your hands thoroughly5
- Clean the blister and surrounding area with an antimicrobial wound solution
- A sterile needle is preferred but a small sewing needle cleaned with isopropyl alcohol will suffice9
- Pierce the bottom edge of the blister, creating a small hole for the fluid to drain out by gravity9
- Don’t remove the overlying skin – it’s still an effective barrier protecting the tissues below 9
- Apply a new (unopened) dressing, ensuring it seals around the area to prevent contamination.5 You could also apply an antimicrobial contact layer under the main dressing. This would offer additional protection from infection and prevent accidental removal of overlying skin when the dressing is removed.1
Please keep in mind this may not be recommended for those at higher risk of infection, e.g. diabetics or immunocompromised people.6
When to see a doctor about a blister
Most blisters heal in a few days and don’t need medical attention.
However, if your blisters are spreading, itchy or occurring on the skin where there has been no rubbing or friction, it’s time to visit your doctor, as these signs could be related to a disease or allergy.6
Another important reason to consult your doctor is if you notice any signs of infection:
- increased warmth, redness or swelling around blister5
- pus or discharge from blister5
- increasing pain around blister5
- blister is not healing7
- blister has a bad smell7
If you have conditions like diabetes, vascular disease or weakened immune system, you must be more watchful for these signs.6 Don’t hesitate to see your doctor – infections rarely get better by themselves.
Ongoing management
- Monitor the area for any signs of infection – increased redness, pain or ooze. Feeling generally unwell or developing a fever may also indicate infection and you should promptly seek professional medical attention.4
- Dressings don’t need to be changed daily. Every time a dressing is removed, there is an opportunity for contamination and disruption of the healing process. Modern wound care products are designed to remain in place for several days. Check the product instructions or discuss with a qualified clinician.1
- Give it time to heal – avoid activities that will aggravate the injury.3
FAQs
What causes blisters during exercise?
When an area of skin is subjected to repeated rubbing or friction, the top layers of skin get separated. Dampness too, can increase the likelihood of blisters forming.3
How do you prevent blisters from forming?
- Wear shoes and socks that fit well and are not worn out.
- Look after your skin.
- Break in new shoes before wearing them for long periods or distances.
- Be aware of pressure points and protect them with padding, gloves, or specialist equipment.
- Prevent moisture build up in vulnerable areas. Certain creams and powder might be helpful.
Should you pop a blister or leave it?
Draining the fluid may be a reasonable option if an intact blister is large, causing pain, limiting movement or in a location where it may rupture accidentally.1 This requires caution, a clean or sterile needle, a suitable dressing and a clean environment to prevent infection.3
What is the best treatment for blisters on feet?
References
1. Carville, K. (2023). Wound care manual (8th ed.). Silverchain Foundation.
2. Cleveland Clinic. (2021, April 30). Blisters. https://my.clevelandclinic.org/health/diseases/16787-blisters
3. (2024, December 20). 8 tips for preventing & treating blisters from a podiatrist. Southwest Foot and Ankle Centre. https://www.swfootandankle.com.au/tips-for-preventing-treating-blisters/
4. Mayo Clinic. (2024, May 1). Blisters: First aid. https://www.mayoclinic.org/first-aid/first-aid-blisters/basics/art-20056691#:~:text=Prevention,the%20risk%20of%20blisters%20forming
5. Weatherspoon, D. (2023, February 2). When and how to pop a blister. https://www.healthline.com/health/should-you-pop-a-blister
6. LeWine, H.E. (2023, November 21). Friction blisters. Harvard Health Publishing. https://www.health.harvard.edu/a_to_z/friction-blisters-a-to-z
7. International Wound Infection Institute (IWII). (2022). Wound infection in clinical practice: Principles of best practice (3rd Ed.). Wounds International.
8. American Academy of Dermatology Association. (n.d.).How to prevent and treat blisters. https://www.aad.org/public/everyday-care/injured-skin/burns/prevent-treat-blisters
9. WebMD. (2023, May 06). Understanding blisters – Treatment. https://www.webmd.com/skin-problems-and-treatments/understanding-blister-treatment
Tracey Aldis
Clinical Nurse Consultant
Tracey is a Clinical Nurse Consultant with over 30 years of experience. She has completed a Bachelor of Nursing (RN) and holds advanced qualifications in palliative care, chronic disease management, stomal therapy, continence, and wound management. Tracey is passionate about empowering individuals on their health journeys through holistic support and education and is also certified as a trainer and assessor.