I'm just wondering, if you were to design a worksite fitness or wellness program, what would you include?

That Depends: Upon your goals. This is a broad topic...How big a company, is there room for a fitness facility, etc. Many companies hire business consultants to help them create fitness programs. Take a look at what safeway stores has done to incentivize their employees. Programs that enable weight training, aerobic conditioning and yoga would be ideal.

Wellness, Anti Aging: I would craft a program to address healthy diet, weight training, aerobics, meditation/yoga/chi gong, avoiding self-destructive habits like smoking, drinking and drugs. Spirituality would be encouraged as well. People would be incentivized to participate. Perhaps even some healthy competition could be encouraged at various fitness levels. Health and prevention education would be provided.