After continuous exercise, the hamster is eventually slimmed down and made athletic. After becoming fit, he would be able to detect hint coins for Layton and Luke. When Luke returned the Hamster to Macaroon he eventually went back to his old ways and put on weight.
With Luke's help, this little guy managed to get in shape. However, the mountain of delectable food scraps back at home proved to be too much temptation, and upon returning to the train, the poor hamster returned to his old, sedentary ways.