I really need to lose some weight. 我真的需要减肥了。

Why don't you attend an aerobic class? 你为什么不去参加一个有氧健身班呢?

It might be a good idea to join a fitness center. 您可以参加健身俱乐部。

You need to work out. 你需要去锻炼一下。

I exercise every morning by jogging. 我每天早上做慢跑运动。

I go to the gym a lot. 我常去健身房。