A 2005 study of 93 prostate cancer patients by University of California-San Francisco and Memorial Sloan-Kettering Cancer Center found that a group who switched to a healthier diet and followed a regimen of moderate aerobic exercise, yoga and meditation were able to lower their PSA levels over a one-year period, while those who didn't make those lifestyle changes saw their levels rise. Seventy percent of the exercisers who ate right also saw the growth of their tumors inhibited, versus 8 percent of the control group. None of the lifestyle-change subjects had any other treatment for cancer, while some members of the control group needed surgery, radiation or chemotherapy because their disease had progressed. Patients in the lifestyle-change group also reported marked improvements in quality of life, according to researchers [source: University of California-San Francisco].
It's not clear exactly how much more aerobic exercise helps to improve prostate health. The Mayo Clinic, however, notes that doing aerobics is an important tool in controlling weight problems, and weight problems may stimulate hormone production that causes prostate woes [source: Mayo Clinic].
Yoga and meditation, however, seem to be beneficial because they help reduce stress; stress can trigger production of hormones that harm the prostate. A study published in 2004 by Tufts University researchers, in which 10 prostate cancer patients adopted a healthier diet and also did yoga and meditation to develop more mindfulness, found that three of the 10 were able to reduce their PSA levels, and another five were able to slow the rate of increase. Only two of the 10 saw no benefit [source: Health and Age].