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Skin Findings in Runners: More Than Just Black and Blue Toes

Skin Findings in Runners: More Than Just Black and Blue Toes

Plantar warts. Human papillomavirus is responsible for causing plantar warts. While there are a lack of epidemiological studies, several factors associated with exercise can predispose runners to plantar verrucae, including trauma and perspiration related maceration of the epidermis.1 Differentiating running-related calluses from warts is important, as these conditions may appear clinically similar. Additionally, callused skin may harbor plantar warts and should be examined carefully for the presence of capillary thromboses after paring of the lesion.1,12 

Plantar verrucae clinically present as hyperkeratotic, endophytic papules with sloped sides and a central depression on the soles of the feet.14 They may also coalesce into larger plaques, forming a mosaic wart.14 When present on the soles, patients may report pain and limited physical activity.1 

Treatment aims to destroy the wart using cryotherapy or through application of topical agents such as cantharidin or keratolytic agents (eg, salicyclic acid or tricholoroacetic acid).12 However, in runners, these treatments may prevent timely return to activity. Therefore, topical imiquimod with occlusion is an effective treatment for athletes.1 Paring of the verrucae may also be used to reduce pain.1 To prevent transmission of the virus, athletes should keep their feet dry and wear shoes or sandals in common areas.12  

Frostbite. Runners that brace cold weather without the proper precautions are at risk for developing frostbite. This typically occurs on unprotected areas of skin, such as the nose, cheeks, or ears when they are exposed to below-freezing temperatures. Initially, the affected area becomes numb and discolored (ie, blue-purple). Swelling, stinging, or burning may also occur. After 24 to 36 hours, a blister may develop, which usually resolves in an additional 2 weeks.1 

Treatment involves rewarming of the affected area in a 38 °C to 44 °C water bath for 20 minutes.1 To avoid damage from recurrent cycles of freezing and thawing, rewarming should not be performed if the skin will be re-exposed to freezing temperatures.12 In the case of blister formation, some authors suggest the drainage of clear blisters but not hemorrhagic blisters.12,15 

Elevation of the affected area, tetanus prophylaxis, topical aloe vera, pain management, and nonsteroidal anti-inflammatory drugs (NSAIDs) should be used to promote healing.12,15 Patients suffering from severe wounds should be treated expectantly to allow for wound demarcation followed by surgical debridement or amputation if indicated.15 

Frostbite can be avoided by wearing sufficient clothing for the outdoor temperature. It is wise to layer loosely fitted clothing, as the air between layers may act as an insulator. Wet clothing should be changed promptly. Additionally, applying heavy lotions or creams before running can help to trap heat near the skin and preserve warmth.1 

Skin cancer. The increased amount of sun exposure seen in outdoor runners is concerning, as exposure to UV radiation increases risk for sunburns and skin cancers. The cumulative amount of UV exposure in a lifetime increases the risk for basal cell carcinoma, squamous cell carcinoma, and melanoma.12 A study performed at the Ironman Triathlete World Championships found that despite wearing water-resistant SPF 25+ sun protection, all participants developed a sunburn following the competition.16 An observational cohort study targeting marathon runners discovered they had higher referral rates for removal of skin lesions concerning for nonmelanoma skin cancer when compared with nonrunners.17 The same study also found that marathon runners had higher rates of atypical melanocytic nevi and solar lentigines than the control group, which are strong indicators for an increased risk for malignant melanoma.17  

Most sunburns present as sharply demarcated areas of erythema that can be easily diagnosed upon examination. More advanced burns may have blistering and, if severe, may present with fever, chills, and nausea.12 Once sunburns have been acquired, the damage caused to the skin cannot be reversed. Minor burns can be treated with cool water or a Burrow’s compress.1 Blistering sunburns may require a nonsteroidal anti-inflammatory drugs for pain control as well as topical petrolatum jelly, warm soaks, menthol-containing lotions, or topical corticosteroids.1 The key to decreasing sunburns and skin cancer risk in athletes is prevention. Athletes should make certain to use sunscreen with an SPF of 30+ consistently, wear photo protective clothing, and avoid sun exposure when possible, especially during hours of peak UV radiation (ie, 10:00 am-4:00 pm).12 

Urticaria and exercise-induced anaphylaxis (EIA). Physical urticarias have been reported in 14% of athletes, with cholinergic urticaria being common in runners.1,2 This form of urticaria occurs in response to body heat generated by exercise, stress, and environmental temperature.1 Affected runners present with small, well-demarcated, pruritic wheels appearing 2 to 30 minutes into exercise. Antihistamine use before exercise in individuals who are affected is the treatment of choice.1 

EIA is a more severe, life-threatening form of physical allergy that can occur in runners. The risk of this condition is highest in individuals with preexisting food allergies and literature suggests that eating before running may predispose athletes to EIA.1 The mechanism by which EIA occurs is still unclear, but it is hypothesized that mediators such as IgE, lactate, or creatinine phosphokinase released during exercise cause mast cell degranulation and resultant high levels of histamine.11 The initial symptom is typically pruritis with or without a coexisting skin rash. EIA may then progress to cause angioedema, urticaria, gastrointestinal symptoms, respiratory symptoms, and respiratory or vascular collapse.11 

Treatment is aimed at providing vascular and respiratory support while administering antihistamines and epinephrine. EIA can be avoided by refraining from eating right before exercise and abstaining from exercising in extremely hot, cold, or humid weather.18 It has also been found that avoiding aspirin or NSAIDs before exercise reduces episodes of EIA. Runners with EIA should be counseled not to run alone and to carry epinephrine during exercise.1

The most common skin disorders seen in runners vary greatly in their origin, presentation, prognosis, and management. It is important for dermatologists to be able to recognize and diagnose the discussed conditions as to provide patients with both timely and accurate treatments.

Ms Hunt is a medical student at University of Illinois at Chicago, College of Medicine. Dr Ashack is practicing dermatologist at Dermatology Associates of West Michigan and Assistant Professor at Michigan State University College of Human Medicine

Disclosure: The authors report no relevant financial relationships.

1. Mailler-Savage EA, Adams BB. Skin manifestations of running. J Am Acad Dermatol. 2006;55(2):290-301. doi:10.1016/j.jaad.2006.02.011

2. Helm MF, Helm TN, Bergfeld WF. Skin problems in the long-distance runner 2500 years after the Battle of Marathon. Int J Dermatol. 2012;51(3):263-270. doi:10.1111/j.1365-4632.2011.05183.x

3. Cohen PR, Schulze KE, Nelson BR. Subungual hematoma. Dermatol Nurs. 2007;19(1):83-84.

4. Basler RS. Skin injuries in sports medicine. J Am Acad Dermatol. 1989;21(6):1257-1262. doi:10.1016/s0190-9622(89)70340-6

5. Orava S. About the strains caused by a marathon race to fitness joggers. J Sports Med Phys Fitness. 1977;17(1):49-57.

6. Nequin N. More on jogger’s ailments. N Engl J Med. 1978;298(7):405-406. doi:10.1056/nejm197802162980721

7. Mailler EA, Adams BB. The wear and tear of 26.2: dermatological injuries reported on marathon day. Br J Sports Med. 2004;38(4):498-501. doi:10.1136/bjsm.2004.011874

8. Auger P, Marquis G, Joly J, Attye A. Epidemiology of tinea pedis in marathon runners: prevalence of occult athlete’s foot. Mycoses. 1993;36(1-2):35-41. doi:10.1111/j.1439-0507.1993.tb00685.x

9. Lacroix C, Baspeyras M, de La Salmoniere P, et al. Tinea pedis in European marathon runners. J Eur Acad Dermatol Venereol. 2002;16(2):139-142. doi:10.1046/j.1468-3083.2002.00400.x

10. Caputo R, De Boulle K, Del Rosso J, Nowicki R. Prevalence of superficial fungal infections among sports-active individuals: results from the Achilles survey, a review of the literature. J Eur Acad Dermatol Venereol. 2001;15(4):312-316. doi:10.1046/j.0926-9959.2001.00289.x

11. Adams BB. Dermatologic disorders of the athlete. Sports Med. 2002;32(5):309-321. doi:10.2165/00007256-200232050-00003

12. Adams BB. Sports Dermatology. Springer; 2006.

13. Lipner SR, Scher RK. Onychomycosis: clinical overview and diagnosis. J Am Acad Dermatol. 2019;80(4):835-851. doi:10.1016/j.jaad.2018.03.062

14. Reinhard K, Lenz P. Human papillomaviruses. In: Bolognia J, Schaffer J, Cerroni L, eds. Dermatology. 4th ed. Elsevier; 2018:1383-1399.

15. Smith ML. Environmental and sports-related skin diseases. In: Bolognia J, Schaffer J, Cerroni L, eds. Dermatology. 4th ed. Elsevier; 2018:1569-1594.

16. Moehrle M. Ultraviolet exposure in the Ironman triathlon. Med Sci Sports Exerc. 2001;33(8):1385-1386. doi:10.1097/00005768-200108000-00021

17. Ambros-Rudolph CM, Hofmann-Wellenhof R, Richtig E, Müller-Fürstner M, Soyer HP, Kerl H. Malignant melanoma in marathon runners. Arch Dermatol. 2006;142(11):1471-1474. doi:10.1001/archderm.142.11.1471

18. van der Worp MP, ten Haaf DSM, van Cingel R, de Wijer A, Nijhuis-van der Sanden MW, Staal JB. Injuries in runners; a systematic review on risk factors and sex differences. PLoS One. 2015;10(2):e0114937. doi:10.1371/journal.pone.0114937

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