[Mod Note: This question received an answer that seemed worth curating. See the answer by LW user hereisonehand for the curation notice]
I’ve been weightlifting for a while, and I’ve heard vaguely good things about it’s effect on productivity, like a general increase in energy levels. A recent quick google search session came up empty. If someone looks into the literature and finds something interesting I’ll pay a $50 prize.*
Assume the time horizon is <5 years. I’d prefer answers focus predominantly on productivity benefits. Effects on cardiovascular could be part of an analysis, but would not qualify on their own. If the evidence is for something clearly linked to productivity, like sleep, I’d count that. Introspective evidence will also not qualify. Comparisons to other forms of exercise would be especially interesting. Assume a healthy individual, although I’m at least somewhat interested in effects on individuals with depression or anxiety given their prevalence.
*Prize to go to best answer, as judged by me, if there are any that meet some minimal threshold of rigor, also as judged by me.