Sunscreen Use and Sweat
Production in Men and Women

Araǵon-Vargas L. Journal of
Athletic Training. 2016;(51):696-700

Take Home Message:
Athletes need to use sunscreen when exercising outdoors; however, they need to
be selective and ensure the sunscreen is not impeding effective sweating.

is imperative for athletes to be protected from solar radiation during physical
activity, particularly in hot environments. Several researchers investigated
clothing to protect from solar radiation without compromising sweat production
and evaporation, but there is minimal research examining the effects of
sunscreen. Though the use of sunscreen is advocated, there has been no research
on sunscreen’s influence on sweat production and evaporation. Therefore, the
authors measured the effects of 2 water-resistant sunscreen products on local
sweat production among 20 athletes (10 males, 10 females) following 20 minutes
of cycling (78-80% maximum heart rate) in the heat (30o C; 58%
relative humidity). They compared these effects with the application of an
antiperspirant, which inhibits sweat production. The athletes reported to the
laboratory on 2 consecutive days at the same time, and their urine specific
gravity and dry body mass were recorded. The researchers used both subscapular
regions, which allowed 2 treatments to be randomly tested during each session: sunscreen
A (active ingredient,), sunscreen B (active ingredient, titanium dioxide), no
lotion, and antiperspirant. As the sunscreen was drying (~60 minutes) the
authors measured the athletes’ temperature and applied sweat patches over the
applied lotion. After the exercise the authors removed the sweat patches,
weighed the athletes, and recorded sweat-collection time to calculate local
sweat rate. The authors found scapular localized sweat rate was lower for the
antiperspirant and sunscreen B compared with sunscreen A or no lotion

authors revealed that certain sunscreen can alter sweating and evaporation that
is necessary for thermoregulation. Application of sunscreen B, with titanium
dioxide, to the skin hindered sweat production to the same extent as an antiperspirant.
Sunscreen A, with oxybenzone, had no measurable effect on local sweat rate when
compared with the use of no lotion. Both sunscreens were commercially available
with the same SPF; however, they differed in active ingredients. The
antiperspirant decreased local sweat rate 25.5%, where sunscreen B reduced
local sweat rate by 17% and sunscreen A reduced it by only 12.5%. Though, it is
difficult to determine if this difference is clinically significant, or which
active ingredients within the sunscreens are primarily impacting
thermoregulation, deciding which sunscreen to use is an important factor to
consider when preparing athletes for outdoor activities. These changes in local
sweat rate could lead to increased risk for heat illnesses. Therefore, medical
professionals should consider advising athletes who are active outside in the
heat to limit the use of antiperspirants and sunscreens with the active
ingredient titanium dioxide on large skin areas. Additionally, medical
professions should continue to educate athletes on proper hydration,
acclimation, and implementing sunscreen use during outside physical activity.

Questions for
Discussion: Do you provide sunscreen or sunscreen education to your athletes?
Have you considered that sunscreen could hinder thermoregulation? If so, have
you seen a sunscreen that is best for outdoor physical activity?

Jane McDevitt, PhD
by: Jeff Driban


Sunscreen Use and Availability among Female Athletes

Aburto-Corona, J., & Aragón-Vargas, L. (2016). Sunscreen Use and Sweat Production in Men and Women Journal of Athletic Training, 51 (9), 696-700 DOI: 10.4085/1062-6050-51.11.01