Anyone who has seen a professional rower at work can testify they often have a very sculpted body as a result of their training. But they do not achieve this solely by training on the water; to reach professional level, rowers also practise muscle-building exercises in the gym. Here is one of their training routines.
You have to take a weight that you can lift 30 or even 40 times in a row. It can seem light at first, but at the end your muscles won’t be able to take it any more. This is conditioning training.
-Bench press with weights
And of course doing some rowing can also greatly help you improve body conditioning and cardio.