"Train close to failure, not just heavy Many people go to the gym for years without visible change because they confuse lifting heavy with training effectively. The research shows that muscle fibers are recruited from smallest to largest, so even a lighter weight set driven close to failure forces the largest fibers to take on a disproportionate load, producing "a similar amount of mechanical tension" as heavy sets. The practical guideline: stay between 5 and 30 reps per set, and push each set to within a couple of reps of failure — regardless of the weight on the bar. Source: Lane Norton, Forever Strong Experience, Nutrition and Body Composition Episode"