What is the main difference in defensive use of a rising block and a downward block?

The main difference in the defensive use of a rising block (Age Uke) and a downward block (Gedan Barai) lies in the target area they protect and the type of attack they are designed to deflect. Age Uke is primarily used to defend against attacks directed at the upper body, specifically the head and face. It's an upward sweeping motion intended to intercept and deflect incoming strikes like punches or downward strikes. The purpose is to create a strong barrier to protect the head and potentially disrupt the attacker's balance. In contrast, Gedan Barai is used to defend against attacks directed at the lower body, such as kicks to the legs or groin. It's a downward sweeping motion used to deflect or block incoming low attacks. Gedan Barai protects the lower body, making the practitioner less vulnerable to sweeps or strikes to the legs. For example, if an opponent attempts a front kick to the face, Age Uke would be the appropriate block. If the opponent attempts a sweep to the legs, Gedan Barai would be used. The blocks are defensive methods to be used for different attack vectors.