Брет Контрерас "Анатомия силовых упражнений с использованием собственного веса в качестве отягощений" http://padaread.com/?book=168001&pg=1Вообще он профи. PhD. Тренер, исследователь. https://bretcontreras.com/О нем и его книги https://www.amazon.com/Bret-Contreras/e/B00BT96GD6Bret Contreras, PhD, MS, CSCS, has become known in the strength and conditioning industry as the Glute Guy because of his expertise in helping clients develop strong, shapely glutes. In 2015 he earned his PhD in sport science from the Auckland University of Technology in New Zealand, where he studied under biomechanics expert John Cronin. Contreras has conducted numerous electromyography experiments in his research. и дальшеВ общем, доверять можно