Sports

Table-tennis, badminton, and boules are already at Cubertou for your enjoyment.
Bathing: There is an Olympic swimming pool (open air in summer) at Fumel (7 minutes by car) and a smaller, open air pool in Puy l'Eveque (15 minutes by car). There are also quiet and well-maintained swimming lakes at Frayssinet-le-Gelat (10 minutes drive) and Cazals (20 minute drive) with a sandy beach.
Riding: There are several excellent stables in the area (good for beginners also), offering accompanied rides on a good network of off-road pathways.

riding

Tennis: Public tennis court in the village (St Martin le Redon).
Fishing: (Well, kind of.) The trout-farm in the village (St Martin le Redon) provides lines and bait; "pay by the kilo" for your own catch in a pretty lakeside setting.
Bicycling: Mountain bikes can be rented at Vire-sur-Lot (15 minutes by car) and Montayral (8 minutes).
Water sports: A centre, including kayak/canoeing, at Puy l'Eveque on the Lot river, has the striking backdrop of this classified medieval village. A little further afield, there are several companies offering canoeing or kayaking down shallow stretches of the Dordogne river (e.g. from Souillac) and returning you to your starting point by car.
Rock-climbing: There are marked and graded routes for experienced climbers on the cliffs (visible from Cubertou across the valley) in Sauveterre-la-Lémance. Beginners should contact the local club at Montcabrier.