Other characteristics related to their hunting heritage are a size suited for scrambling in and out of boats and an inordinate love for water. Golden Retrievers are exceptionally trainable—due to their intelligence, athleticism and desire to please their handlers—and excel in obedience trials. They are also very competitive in agility and other performance events. Harsh training methods are unnecessary, as Golden Retrievers often respond very well to positive and upbeat training styles. Golden Retrievers are known to have genetic disorders and other diseases. Hip dysplasia is common in the breed; when buying a puppy, the pedigree should be known and be examined by the OFA or by PennHIP for hip disease. Obesity is also common in the breed because Golden Retrievers love to eat. Puppies should eat about three cups of food a day and adults three to five cups, depending on the food and how active the dog is.