Weightlifting positively impacts metabolism by promoting increased muscle mass, which subsequently raises the resting metabolic rate (RMR). As muscle tissue burns more calories at rest than fat, adding strength training to a fitness regimen can lead to more efficient calorie usage. Moreover, lifting weights creates an afterburn effect, known as excess post-exercise oxygen consumption (EPOC), where the body continues to burn calories at an elevated rate post-workout. This metabolic boost not only aids in weight management or loss but also enhances overall energy levels and fitness performance.