Thus a local conformational change initiated by the agonist, but not antagonist binding results in a destabilization of the protein structure. This destabilization is not strong enough to denature the protein, but results in a long range effect across the protein affecting its active site several angstrom away from the ligand binding site. This is known as an allosteric mechanism. As a rule, agonists induce structure destabilization, while antagonists merely bind , but do not affect the protein structure (or trigger a conformational change that locks a protein in its inactive position). One way to visualize the action of ligands on receptors is to realize that proteins constantly undergo conformational changes which is best described as an equilibrium between an active and inactive, or even among multiple states, including desensitized states (different types of inactive states). Agonists and antagonists shift this equilibrium towards an active or inactive conformation, respectively.
Weider had enjoyed some success as a bodybuilder but far less as a weightlifter, and vehemently disagreed with the AAU rules that Hoffman had helped draft. Requiring that a bodybuilder shoulder-press 200 pounds, for instance—something that Weider struggled and, at times, failed to do—made little sense in the context of what was essentially an aesthetic contest. Moreover, Weider argued that Hoffman was unfairly overlooking African American athletes with impressive physiques, citing Melvin Wells’s failure to claim the Mr. America crown on several prior occasions. During the late 1950s and early 1960s, Weider would attempt to remedy these oversights by using his publications to promote the careers of black bodybuilders such as Rick Wayne, Harold Poole, and Chris Dickerson. But for Weider, racial equality came second to aesthetics: He was willing to consider anyone as a possible champion, so long as they had the look he prized.