The recommended way to build muscle mass involves a combination of resistance training and proper nutrition. Engaging in progressive overload with weightlifting or bodyweight exercises is essential to stimulate muscle growth. Adequate protein intake is crucial for muscle repair and synthesis, with many experts recommending around 1.6 grams of protein per kilogram of body weight. Additionally, incorporating rest days allows muscles to recover and grow stronger. Consistency and a balanced diet are fundamental for successful muscle-building efforts.