Here's the article and here's the Metafilter discussion. Many good comments there. I'll just single out:
The really galling thing is that employers put the burden of these 'wellness' programs entirely on the employee. They want employees to walk 10,000 steps per day, for example, but don't provide breaks for employees to go for a walk during the day. If you're a sedentary office worker, this effectively means making the wellness program an unpaid second shift. It's a hell of a racket.
These 'incentive' programs should be legally required to be completable during normal, paid work hours. If an employer wants its employees to go to the gym, then the employer can damn well pay for their memberships and let them count time spent there as work.