Microrelief changes in chronically sun-exposed human skin

The effects of solar exposure on the microtopography of the human skin can be followed, in vivo, by comparing 2 nearby areas, protected and non-protected, of the arm. This has been possible in the case of professional cyclists, whose short-sleeved outerwear provides a clear demarcation of the 2 zones. The microrelief was measured from negative replicas by an automatic image analysis method. The skin pattern showed clear changes between the 2 zones. Results are discussed in an attempt to outline similarities and differences between the effects of the actual aging process and solar radiation.