The Physical Activity Guidelines for Americans suggest that adults complete at least two full-body strength-training sessions each week.
The guidelines also recommend adults do at least 150 to 300 minutes a week of moderate-intensity exercise, or 75 to 150 minutes a week of vigorous-intensity cardio, or an equivalent combination of the two.
But you don’t have to limit yourself to these recommendations. You can do strength training more than two days a week. However, the American College of Sports Medicine suggests that you take at least 48 hours between workouts that train the same muscle groups.