What happens to the active force with a decrease in muscle length?

The relationship between active force and muscle length is called the length-tension relationship. As muscle length decreases, the active force increases until an optimal length is reached. This is because the myofilaments are able to overlap more optimally, allowing for more cross-bridges to form. However, if the muscle is stretched beyond its optimal length, the active force will decrease. This is because the myofilaments are too far apart, and fewer cross-bridges can form.