Dawn,They are not eating enough carbs. Remember that carbs protect protein from being broken down for fuel (gluconeogenesis).
Without enough carbs, protein is broken down and ammonia is formed in the process which can be smelled. Solution: cut back on the intensity of exercise (if they are working out intensly) and eat more carbs.
Hope that helps
Could the smell be coming from the clothing? That’s pretty odd. I have not experienced that but would like to hear from others. Something tells me there’s a cat involved!