Exercises are intended to challenge the body. But, there are times when they may place too much strain on the body. Or, the body may not quite be ready for the movement, for some other reason. When this is encountered, it becomes necessary to modify the exercise, in some way, to make it more suitable.
Reasons for modifying
1. Lack of strength
2. Lack of endurance
3. Insufficient flexibility
4. Struggling with sequence of movements
Each of these reasons may present differently, in different situations. So, it is imperative that proper scrutiny of the exercises being performed is done, at all times.
Methods of modifying
1. Decrease resistance: this can be done through two methods. Either decrease the weight being used to provide the resistance, or, decrease the length of the resistance arm of the lever. While decreasing the weights is rather self-explanatory, decreasing the resistance arm of the lever system can be a little trickier. An easy example of this would be changing the way a push-up is performed. If someone is not strong enough to perform the push-up in the usual manner, i.e. on the toes, the body position can be modified, and it can be done on the knees. This decreases the resistance, and makes the exercise easier.
2. One of the most effective methods of increasing endurance is through interval training. Therefore, it is quite reasonable to use this same method to adjust exercises where a lack of endurance is a hindrance. Interspersing lower intensities, within an exercise, allows a person to continue with the exercise, and therefore increase endurance, as the exercise is intended to do.
3. Where range of motion is the reason for an exercise to be difficult, or for it to be performed incorrectly, the exercise can be adjusted to work only within the range where it can be successfully performed. A decreased range of motion of the exercise allows for the exercise to still be performed, until the flexibility has been improved enough, and the full range can be successfully attempted.
4. Exercises that are more complex should be broken down into their parts, in order for them to be performed correctly. Where learning of a new movement is proving difficult, the movement can be done as a separation of its parts, and then later performed as a complete movement, once each of the parts have been successfully executed. An example of this could be the power clean. On the face of it, it is a complex movement, requiring a near-maximal force exertion. But, it can be broken down into 3 other exercises, for learning as well as progression into this exercise. These would be the dead-lift, high pull, and front squat. These exercises can be done, individually, as both training for, and motor learning of, the power clean.
5. Where pain is the inhibitor, a majority of the time, stopping the exercise is the best course of action. But, there are a limited number of reasons where the exercise could be modified, and the pain avoided without serious consequence. In these cases, one of the most common ways is to decrease the range of motion of the exercise, to avoid that part of the range which is painful. But, another method could be to attempt the same type of movement, but with a slightly different exercise. An example of this might be if squatting causes any back pain, then leg press can be used as alternative leg exercise.