The caps don`t make any sense. And a regular spray leg sleeve doesn't help much either (too soft and to thin for the impact). To be safe get a shinbone protector from soccer (might need to fix it with some duck tape; maybe footballers use the same - since I'm from Europe I have no clue about football...) and if you realize that you seldomly (never) fall on your offside-turns with a release of the boot you can get rid of it...