Fruit juice is horrible to drink during your workout. This makes your body demand more liquids and increases your thirst. The only thing you should be drinking during a workout is water. This will refresh your body and replenish your body. Some people think it is wise to drink energy drinks during a workout. This isn't a good idea either. Any doctor and health trainer will tell you the only thing you should drink is water when you are working out.
After a workout, you can go to the juice bar and order a nice mixed juice to drink. This will help you with energy after your workout is finished. However, even when I do this I find out that I crave more and more water after drinking the juice. I don't find that it helps me to regain my energy level after the workout. However, if I wait an hour or two after my workout and then drink a juice this one tastes wonderful and I can feel the difference it does make.