We wear our watches and trackers through workouts, work and sleep. The strap stays against our skin for hours at a time.
A wearable is useful because it can follow most of your day. It records a run, counts the walk home and tracks your sleep that night. For many of us, the band comes off far less often than the rest of our training kit.
That means repeated contact with sweat and skin, often without much time between wears to clean and dry it.
Eccrine glands, found across most of the skin, produce sweat that is mainly water. It also contains sodium and chloride, along with smaller amounts of substances including lactate and urea. When the water evaporates, dissolved material can remain on the surface. [1]
A worn band also picks up skin oils, shed skin cells and products such as sunscreen or moisturiser. Research on worn textiles describes how skin secretions, debris and microorganisms transfer to fabric through contact. It is more than dried sweat alone. [2]
Fresh eccrine sweat has little odour. Much of body odour develops when bacteria naturally present on skin break down compounds in skin secretions. Some of the resulting molecules, including volatile fatty acids, pass into the air and reach your nose. [2]
On fabric, retained skin oils and other residues can provide material for further microbial activity. The fabric can also hold and release odorous compounds already transferred from the skin. Moisture, drying conditions and the type of fibre all affect that process. [2]
This helps explain why a band can still smell after the sweat has dried, and why letting it dry is not the same as cleaning it.
In a study of 26 people, researchers collected T-shirts after a cycling session and assessed them after 28 hours of incubation. The polyester shirts smelled stronger and less pleasant than the cotton shirts, and the fabrics supported different bacterial communities. [3]
That was a clothing study, not a test of watchbands or AFTERSWEAT. It shows why material is worth considering, rather than treating every sweaty item the same way.
A woven band, silicone strap and leather strap may need different care. Follow the strap maker’s instructions, check whether it allows this type of cleaner, and spot-test first.
We made AFTERSWEAT for the washable band you wear every day. It is ready to use: spray the strap, leave it for a few minutes and let it dry fully before wearing. There is no mixing step.
It is a strap cleaner, not a disinfectant or a treatment for skin. Keep it away from your wrist and the watch electronics. If wearing a band makes your skin sore, take it off and follow the device maker’s advice. Seek medical advice if the irritation persists.
How to use AFTERSWEAT →These sources describe sweat and textile odour. They do not test AFTERSWEAT or establish its performance on a particular strap.