Got a post-workout rash? Blame your sweat.

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Got a post-workout rash? Blame your sweat.

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You love hitting the gym or lacing up to go for a run, but you’re often plagued by itchy, red skin afterwards. Could you possibly be allergic to your own sweat? Well, the answer is (unfortunately) a resounding “yes,” says Dr Mark Tang, consultant dermatologist at The Skin Specialists and Laser Clinic, Mount Alvernia Medical Centre.

As much as sweating is a natural bodily function, some people’s sweat actually irritates and causes skin inflammation. If that sounds like you, it doesn’t mean you’ll have to give up exercising. Dr Tang explains how sweat and skin sensitivity are related.

● Why does sweat lead to more sensitive skin?

Sweating is a well-recognised cause of skin irritation in some people. In fact, there is good medical evidence that some individuals, especially those with atopic eczema, are truly allergic to their own sweat!

Skin irritation can be caused by the body heat generated during sweating. Perspiration also contains a sweat ‘protein’ that can induce an allergic or inflammatory response in some susceptible individuals.

Finally, persistently moist, sweaty areas around and between skin folds – such as the inner thighs and armpits – are predisposed to bacterial or fungal infections of the skin, which worsen skin irritation.

● Why are eczema sufferers more prone to sweat sensitivity?

Ceramides, which are naturally occurring lipids, are one of the key components of the ‘cement’ that holds our skin cells together. This ‘cement’ provides structural integrity to the skin barrier and also forms a waterproof seal over the skin, protecting us from external elements such as germs, dust and allergens. In many patients with eczema or inflamed skin, there is a decrease of ceramides, leading to a disrupted skin barrier that is prone to water loss and increased irritation from outside elements.

● Does sweat actually cleanse the skin or detox the body?

The main function of sweat or perspiration is to regulate body temperature, which has to be kept constant at all times. So, as long as your core body temperature is increased, sweating will kick in to help you reduce the temperature through heat loss via evaporation.

Sweat also contains some antimicrobial substances that protect us from skin infections, but it does not actually cleanse the skin per se. It also does not detox the body as sweat does not break down or excrete toxins. Nonetheless, nothing beats the endorphin high after a good, sweaty workout!

● What can someone do if their sweat stings their skin after working out?

Moisturising is actually important before and after exercise. During exercise, especially long distance running or cycling, use a thick, waxy moisturiser over areas of high friction, like the inner thighs, armpits or soles, to prevent skin abrasions.

To prevent irritation from sweat, wear light, breathable sportswear that facilitates quick evaporation of sweat. Gel-based moisturisers are less occlusive and more effective for active sporty individuals.

Additionally, avoid prolonged exposure to sweat on the skin by wiping it off regularly and showering immediately after exercise. Afterwards, use a good moisturiser to maintain and protect your skin’s natural barrier.

● Does prolonged sun exposure lead to more sensitive skin?

Yes, ultraviolet (UV) light from the sun causes cellular DNA damage and skin inflammation, which can affect the integrity and function of the skin barrier. There will be redness, irritation, dryness and itch.

Sun-related rashes tend to affect prominent exposed areas such as the cheeks, front of the nose and V of the neck. So, we should always try to minimise unnecessary UV exposure – and definitely avoid getting sunburn at all cost!