Because of the size and weight of the body armor, the mobility will become very poor after wearing, as well as not wearing. Modern military and police equipment can withstand ak47, m16 rifle bullets, the weight is not as large as imagined 10 kilograms. In fact, it is now often the high-defensive body armor that is often formed by a lower-level soft body armor plus a high-level hard bulletproof panel.
And a piece can meet the U.S. level 4 bulletproof standard, the weight is generally less than 2 kg. Take the Active Interceptor body armor of the U.S. military, for example, the outer tactical vest and KM-2 Kevlar lining weigh 3.8 kg, at this time to reach the U.S. 3A level of protection, in addition to the protection of pistol projectiles, but also can protect from submachine guns fired 9mm calibre gun projectiles or grenades. After adding 1.8kg of borbid carbide ceramic panels on both sides, the "Interceptor" has increased its mass by 3.6kg, with a total weight of 7.4kg, and the protection level has risen to IV level, which can defend against close-range shooting of 7.62X51mm armor-piercing projectiles.
You can also increase the guard and neck, which weighs more than 8kg. As can be seen from this, even with a comprehensive and high level of protection, the total weight will not exceed 10 kg. Of course, the increase in the weight of a single soldier's load is bound to affect the convenience of the operation, so often soldiers will be based on the mission needs of a reasonable selection of bulletproof vest panels, so as to achieve as light weight as possible to achieve the most efficient protection. But to say that because of the impact of mobility, it is better not to wear, it is certainly a wrong idea. Many wars and combat experiences have taught us that body armor can greatly reduce casualties. The experience of our peacekeeping forces also shows that the soldiers in the last 92-step battle, thanks to body armor, did not have more personnel to sacrifice. Bulletproof vests are obvious to the extent to which soldiers' lives are protected, not that they are light enough to run fast enough to survive. Like tanks to increase defense capabilities are at the expense of mobility, but now no one with thin-skinned cars carrying artillery as the main battle tank makes it?