Many work places now have showers to support workers doing some sort of work out during the day... but well over 20 years ago I was commuting to a place that did not have such... then I did a wet wipe down in the men's room with a large terry cloth and then toweled off. I would drape the towel and wash cloth over my bike to dry and use them for a few days before washing.

Later a fellow emplyee and I rigged a shower in the building utility room... simple thing. I stood on a pallet over a floor drain next to the water heater. Shower head looped overhead with a simple curtain.

You might ask your employeer if you can rig something up.