In reply to notaclue:
It's a warm weather thing.
Yes, plasters are fine, as long as they don't fall off. I have found it better to buy boxes of dressing strips so I could cut big chunks off, and that for staying power, the order of merit is Lidl's>Boots>Elastoplast>Sainsbury>Superdrug.
The top you wear also makes a big difference, and it's not always obvious why. Under Armour is better than Nike, I find.