The Overload Principle is one of the fundamental concepts in fitness training. Basically, in order to continue improving results an exercise must continually become more challenging. Your body will adjust to a workout and you must continue to add stress in order to achieve more.
For example, if you are weight training, you must continually add weights to the bar week over week for your lifts to improve. By increasing the load you put on your body, you can make sure that your gains don't stall. The intensity of your workouts must be high enough to cause physiological adaptation in order for your muscles (and strength) to grow.
For any athlete looking to perform at a high level, this basic fundamental must be mastered. You can ensure you're overloading your muscles by adding more weight to exercises, increasing the number of reps, and using different exercises.
For example, bodybuilders will often change their workout routine every few weeks to make sure they are always challenging their muscles. They might also change exercises for the same muscle groups in order to get maximum growth.
It's a good idea to stay away from extreme overtraining as your body needs time to recover. But do not make the mistake of avoiding overtraining altogether. If you notice your progress is slowing down, it could be that you are no longer overloading your muscles.
Overload your muscles with these tips:
Increase the weight in each workout
This is one of the simplest ways to overload your muscles. Simply increase the weight you are lifting on each exercise and your muscles will have to adjust. For example, if you do leg presses with a 200lb barbell, make sure you continue to increase the weight until you reach over 300lbs.
Increase the number of reps you perform
Another way to overload your muscles is to perform more repititions than you're used to. Most people stick to low reps for each weight training exercise, but high reps can also be very effective. You can try doing 3 sets of 10 reps instead of 5 sets of 5 for each exercise. Your body will grow and adapt from these workouts!
Change your workout routine regularly
Your body will eventually get used to a workout and will no longer be challenged by it. Changing your routine every few weeks is a great way to make sure that doesn't happen. If you tend to stick to specific exercises, try changing them up - try new machines or exercises instead of just keeping to the same old ones!
Use different exercises for the same muscle groups
You can overload your muscles in other ways besides increasing the amount of weight you lift or the number of reps you do. By changing the exercises, you can ensure that your body continues to adapt and grow bigger and stronger. For example, if you're used to doing squats as a strength building exercise for your legs, try doing lunges instead!