Dog Tread describes an assortment of muscle-building exercises dogs can perform while wearing a weighted vest. The International Weight Pull Association sanctions competitions that promote the training of dogs to willingly pull very heavy weights for short distances on a cart or sled. Progressively training a dog to pull heavier weights develops the dog's musculature and add visible muscle mass.
Dogs should not carry more than 10 percent of their own body weight in a weighted vest during exercise. Alternate strength-building days with endurance/cardiovascular exercise days, with at least one rest day per week. The exercises suggested by Dog Tread for building muscle while wearing a weighted vest include repetitions of sit to stand, sit to down, squats, the classic begging position and lifting the front limbs into the air.
The International Weight Pull Association says that the only equipment needed to exercise a dog in weight-pulling is a well-fitted, well-designed freighting harness. The weights pulled by the dog during training can be anything handy. Many people use old tires to exercise dogs in weight-pulling. To avoid injury, the dog should be taught to pull with good form. Good pulling form means the dog drops the head and drives with the hind end forward into the chest straps of the harness.