DIFINATION OF UKC AND DIFFERENCE WITH THE ADBA from John Berman's blog

LET’S DEFINE THE AMERICAN PITBULL TERRIER IN ADBA / UKC STANDARD
To best define the ADBA and UKC standards it is necessary to highlight the difference between the two, as they are both common to have vigor, tenacity and power, but at the same time they are very different because the first association aims at work and the second to the exhibition.
The ADBA tends to push the character qualities of the American Pitbull Terrier as high as possible: aggressiveness, competitive spirit and high temperament; and physical such as resisting fatigue and allowing the dog to work and exercise even in extreme and unfavorable situations, which made it a suitable dog for combat in the past. Physically these dogs are leaner than those of the UKC to improve their performance.
The UKC thinks of the Pitbull with massive tonnage and head called a “brick”, in fact the dog raised with UKC standard has a bigger bone than one of the ADBA standard because over time the interest in aggression has become lost compared to its origins, going towards a dog for family and for an aesthetics suitable for the ” Show”. All this is the result of years of selection to get a dog of greater size but with a level of aggressiveness practically zero, if well-behaved and socialized
MAIN MORPHOLOGICAL DIFFERENCES OF THE STANDARDS
Muscles:The American Pitbull Terrier in ADBA standard having to perform competitive activities has an elongated musculature, which allows rapid shots, leaps and jumps.The UKC standard specimens are endowed with even more imposing, massive muscular masses, but characterized by short fibers more suited to efforts than at competitive level as this subject has nothing to do with fatigue, work.
Size:The ADBA standard wants the weight of the Pitbulls to go from 14 kg to 24 kg. This is because there must be a weighted balance between weight and power to guarantee its agility.The UKC reaches 27kg but accepts even larger subjects that keep the measurements in proportion. Today, in fact, pit bulls are allowed up to 33kg.
Finally we can summarize the two standards in:
the “only practical” one (ADBA) that does not aim at aesthetics, but wants to give the dog the physical and psychological condition that allows it to work and play sports at levels even beyond competition.the “family and aestethic” one (UKC) that points to a smoothing of the character in order to grow the harmless dog, thus aiming at improving the character but also the morphology with a superior aesthetic for Show.