So, a study published in the Journal of Veterinary Internal Medicine in 2012 called "Cachexia and sarcopenia: Emerging syndromes of importance in dogs and cats" discussed the importance of muscle loss in pets. This muscle loss is associated with a higher morbidity and mortality rate in humans. In humans, sarcopenia usually begins around the age of 30 years and progresses throughout life. When the muscle loss is linked to chronic disease there is poor appetite, fatigue, muscle atrophy, and weakness. This article showed that dogs with chronic kidney failure that were classified as underweight had shorter survival times as compared with those classified as moderately overweight. This suggests that as in people, renal cachexia affects survival time.
The article went on to state that as sarcopenia and cachexia are studied more, we expect that recommendations regarding the importance of formulating dietary plans to increase metabolism and encouraging supplementation will be given to dog owners. Exercise is important to delay the breakdown of muscle.
I couldn't have said it better myself! Eat right and exercise! True for you, true for your dog!