No science here, just cold, hard truth: If you want to hit some big time PR’s in the gym, you better get some people around you to help!
Ever tried to plow through a really grueling workout by yourself? Sure, you might get about what you expected out of it, but don’t expect any super-human efforts. If you take the exact same situation and add in some motivated training partners or spotters, you’re damn near guaranteed to blow your old PR out of the water. The best explanation for this is the enhancement of the fight-or-flight response; you’d better fight to move that weight, or get your ass out of the gym before you’re ridiculed to death.
Next time you’re ready to move some big time weights, get some motivated people in there with you and watch the PR’s fall!