I really have a hard time buying into these sorts of studies. That goes for almost anything related to the human body. The study[1] the poster links to consisted of eight men for two days.
The study goes on to say: "Ultradian rhythms of similar frequency were found in perceptual and motor performance. The rhythms in perception, however, were drastically modified by altering the sampling frequency and were, therefore, attributed to statistical artifact."
I guess the questions I have are: As a programmer, am I in pursuit of heightened motor skills? Is this study statistically significant?
[1]http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA296199