Brief Answer:
I suggest a higher spf sunscreen which is water and sweat resistant

Detailed Answer:
Hello. Thank you for writing to us.

I have taken note of your query and I have understood it.

Hi has developed skin tanning.
UV A part of the electromagnetic spectrum is mainly responsible for tanning.

Sunscreen that is ideal for use in swimmers should be broad spectrum (i.e should have both UV A as well as UV B coverage).
Also, it should be water and sweat resistant i.e it should not get easily washed away by swimming and sweating, for it to be effective.
A sunscreen with minimum spf 30 or preferably 50+ is considered broad spectrum.
It should be re-applied every 2-3 hours, regularly, THROUGHOUT THE DAY (e.g 8 AM, 11 AM AND 2 PM) ON ALL SUN EXPOSED SKIN... AND NOT AFTER SWIMMING.
For each application, approximately 3 ml should be used for face & neck and 3 ml for each arm, and 6 ml for torso (i.e 3 ml+3 ml for front and back).
It should be clearly mentioned on the sunscreen that it is water and sweat resistant.

The sunscreen that he has been using probably has an spf of just 26 and is thus not broad spectrum. It is also water based and therefore would get easily washed away with sweating and swimming.

Do not be worried. However you should change the sunscreen to the one which has a higher spf as well as, is water and sweat resistant.

For already existing XXXXXXX he may use a glycolic acid based cream e.g at night to gradually fade away the XXXXXXX
Glycolic acid is available in 6% and 12% strengths in a cream form.
Glycolic acid is an Alpha Hydroxy acid (AHA) and exfoliates XXXXXXX due to excess melanin. It is available in various OTC brands like pond's, nivea, olay etc.
You can check for these OTC brands at a nearby drug store Or you may else visit a dermatologist in your region for a prescription product containing 10% or 12 % glycolic acid.

Regards
Wish him all the best. Hope he becomes a fantastic swimmer!

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Brief Answer:
Use it before swimming and every 2-3 hours

Detailed Answer:
Hi.

He should apply the sunscreen throughout the day.. every 2 -3 hours (e.g 8 AM, 11 AM, 2 PM).
He may apply the sunscreen 15-20 min before he goes out to swim & thereafter every 2-3 hours on all exposed skin, in quantities i mentioned.
Since the sunscreen that you are using is water resistant therefore it won't get washed away with water.
(A water resistant sunscreen means that it will maintain its SPF, as mentioned on it, even after 40 minutes of immersion in water)
Using it after swimming defeats the purpose of using a sunscreen.
A sunscreen role is basically to prevent a XXXXXXX rather than to treat a XXXXXXX

Regards

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