Q: Why is the warm-up important?
A: Firstly, a horse’s metabolism levels increase when you warm up. Through this process energy becomes more easily accessible for the muscles, preparing them for the harder work expected of them during a workout.
Secondly, the amount of oxygenated blood that goes to the muscles increases. Blood vessels widen and the volume of blood being pumped through the heart increases. At rest, a horse of 450kg circulates approximately 900ml of blood per heartbeat. When exercising, this volume may increase to a maximum of around 1,700ml, which is almost double the resting amount. At rest a horse’s heart rate is between 28 and 40 beats per minute. At maximum effort, the heart rate may run up to 245 beats per minute. Therefore, a horse in maximum exercise may circulate a total volume of 416.5l of blood per minute – this is equivalent to 35 buckets of water. Through this increase and expansion, the amount of oxygen supplied to the muscles, along with the amount of carbon dioxide removed from the muscles, increases, reducing the production of lactic acid, which prepares the muscles for the long session of exercise ahead.
The total body temperature and the muscles’ temperature also start rising during the warm-up, preparing the muscles for performance. The elasticity of the muscles increases accordingly as the blood circulation increases, allowing them to stretch and elongate.
Furthermore, the sensitivity of the nerve receptors in the muscles increases. This means that the nerve impulses reach the muscles and tendons more smoothly after a warm-up than if exercise is tackled ‘cold’. This all explains why a horse performing a movement at the start of exercise as opposed to after a good warm-up can appear and feel vastly different.