I am going to lift weights.

我要去舉重。（將來時態）

解析：

舉重 名詞，weightlifting;

舉重，動詞詞組，lift weight（s）。

weight lifter 舉重運動員

be going to 將要幹什麼…

will 將要。

原句的同義語是

I will go to lift weights.

I will go to weightlifting.

I am going to weightlifting.

Lifting weights will build arm and shoulder muscles.

舉重能使手臂和肩部的肌肉發達。

The weight lifter maxed out at 180 kilograms.

舉重運動員使出了最大力量舉起180公斤。