If you need an example of good health, look at tennis star Serena Williams.

Earlier this year, she stunned the pro tennis world by winning the Australian Open, punishing top seed Maria Sharapova.

Her critics said Williams was out of shape and couldn’t complete, following an injury that forced her to miss most of last season.

“I had to work out hard. I remember times where she (the trainer) made me go and I didn't want to do it.  I wanted to do it, but it was had to get that extra mile or whatever it took, it was worth it. I just trained hard,” she said.

Williams says you don’t need a personal trainer or a gym membership to get and stay fit.

“All you need is access to a floor area.  You can do squats, you can do sit ups, you can do push-ups,  you can go running.  I mean, you don't need to a personal gym. It's just important to stay healthy."

Williams encouraged everyone to keep on with their fitness goals.

“The only thing I can say is never give up and always try to look at something that's worse. I can be in that situation instead of where I am, and I just go to the worst case scenario and put myself there and I’m like, well, I can do it.”

Williams did do it again.  Earlier this month, she won the Sony Ericsson Open and she’s looking forward to competing in the French Open and Wimbledon.