Individual factors such as genetics, age, gender, and exercise programme all influence how long it takes to gain muscle mass. Beginners who are weight training for the first time should expect faster improvements in muscle mass than experienced lifters. According to studies, beginner males acquire up to 1-2 pounds of muscle every month, but expert lifters may only add 0.25-0.5 pounds per month. Building muscle mass requires consistent and effective exercise, sufficient diet, and enough recuperation.