Individual cards can indicate so many things, that it's hard to tell if they're indicating sports or physical activity. So you have narrow it down with either your spread or your question. You can ask if the person is interested in sports. A yes card or a sports card means the person is involved in sports, or an athlete. So let's take a look at how you'd know the cards are indicating a sports event, activity or person involved in sports! The cards that, by themselves, indicate physical activity, (the core sports cards are:
If any of these cards shows up with some of the other cards mentioned, you've got a specific sport.
In a horoscope spread, there are two places where physical activity (other than sex!) can be indicated:
5th House: Lovers, children & hobbies
6th House: Routine & things you do to stay healthy
Now if a core sports card shows up in the 2nd House of earned income - ask the cards whether it is indicating a sport - because the person could be making money running a dojo or playing football (5 Wands) , for example, or perhaps own a gym.
2nd House: earned income - for anyone who's making money off their sport.