Isometric contractions are used to build muscle by the muscle fibre staying the same length. These are the muscles that are involved in core strength to be able to stabilise the body. This type of contraction takes longer to build muscle because it only changes the tension of the muscle and not length.
Isotonic contractions are used to build muscle by lengthening (eccentric muscle contraction) and shorting (concentric muscle contraction) the muscle.
Proprioception can be improved by challenging the nervous system. Using things like poles causes a message to the animal’s brain that there is an object that requires them to control their limbs and or body in order to safely move around/over/under an object. The more the brain is tested the better their proprioception becomes and helps prevent falls/slips/trips. This has to be done progressively to ensure it is done safely.
This is possibly an obvious one, but increasing exercise can improve the fitness of the animal. Training enables the muscle of the heart to become more efficient at pumping blood around the body. This is a positive as the body is able to bring more oxygen into the body and get rid of carbon dioxide quicker.
With increasing muscle mass, muscle strength will improve. This does not occur from increasing fibres instead the amount of muscle contractile units (sarcomere) increase.
Posture improvement works by reassuring the animal that they are able to move in a better posture. This is often needed due to previous pain. Training aids can be used to help, although they should not be used all the time. It is important to ensure that the training aid improves the movement of the animal in order to continue using it. Like with any technique or piece of equipment, accommodation can occur. This is where the technique/equipment is not as effective because the body gets used to it.