The Principle of Muscle Gain
Balance – You won’t make any progress if you are hurt. A program that does not include at least as many sets of pulling exercises as it does pushing will set you up for shoulder injury. You also need time for recovery, so make sure your workouts are spaced appropriately and don’t lift heavy more than three times a week. If you are over 35, it is never necessary t go heavy.
Challenge – There is a reason squats and bench presses are used frequently in studies that measure muscle and strength – they work. Base your program around hard exercises that work the most muscles, such as squats, presses, rows, chin-ups, deadlifts, and all their variations.
Specificity – If your goal is to boost your bench press, you need to train on the bench frequently and target your weak points. Doing a high-rep circuit routine won’t help you bench more. Focus on one goal at a time.
Variety – Switch up variables in your workout every one to four weeks. The more advanced you are, the more frequently you should change things.