If researchers could reproduce the biochemical basis for the health- and longevity-enhancing results of exercise, the resulting drug would no doubt be as popular as calorie restriction mimetics. Exercise and calorie restriction are the two gold-standard items for health: little else even comes close yet. From EurekAlert!, news of small steps on this path: researchers "identified two signaling pathways that are activated in response to exercise and converge to dramatically increase endurance. ... Previous work with genetically engineered mice [had] revealed that permanently activating a genetic switch known as PPAR delta turned mice into indefatigable marathon runners. In addition to their super-endurance, the altered mice were resistant to weight gain, even when fed a high-fat diet that caused obesity in ordinary mice. On top of their lean and mean physique, their response to insulin improved, lowering levels of circulating glucose. ... We wanted to know whether a drug specific for PPAR delta would have the same beneficial effects."