When guys who work out regularly do a 12-week weight training program, their body's uric acid goes up more and more as the program goes on, especially by the end — which might mean their bodies are under increasing stress from the workouts.

If guys who lift weights train too much — like a whole lot in a week — their bodies might get stressed in a way that could hurt their performance, and scientists can see this stress through certain markers in their body.

In guys who lift weights a lot, certain chemicals in their urine that show stress on the body are closely linked to both worse performance and more training — meaning they might help tell when someone’s overdoing it.

Taking a specific supplement called HMB-FA before a tough workout might help slightly reduce muscle damage in guys who regularly lift weights, but the evidence isn’t strong enough to say for sure it works.

You can make your workout feel harder and your muscles burn more by resting less between sets—but you can still lift the same total weight without getting weaker.