The question of exercise weights is frequently asked by athletes and fitness buffs alike. In most recommended exercise programs the amount of weight to be used is usually given along with the number of sets and reps. Can you however, give an accurate assessment of how much weight should be used?
In practice I have found that it is impossible to give accurate recommendations in regard to exercise weights. The reason for this is that there are too many differences between the athletes who will be doing the exercises and the sport in which they are involved. This is true not only of athletes, but non-athletes and fitness buffs.
The amount of weight that you use should be determined by the exercise program that you are using. For example, in a 1 x 20 program you use as much weight as you can to complete up to 20 repetitions of an exercise in good form. Good form means that the exercises are done correctly and safely.
Simply overcoming a weight in order to accomplish the exercise should not be done in training. Thus in the 1 x 20 program the amount of weight that you select should allow you to do the 20 repetitions, and no more without breaking form. If you can do more repetitions then you should add more weight to bring you back down below 20. If you can do only 10 repetitions then it is too heavy and you must cut down on the weight.
The same principle applies to other strength training workout routines. Exercise weights should be adjusted according to the number of repetitions that are required. Keep in mind that the amount of weight is regulated in order to do the number of repetitions needed. Sets are used to regulate the amount of energy expenditure required or desired.
Other factors to be considered include training objectives. If you are looking to gain greater strength and/or muscle mass, then you will have to work up to using heavier weights for more sets in your workouts. However, if you are training for speed or explosive power, then you must use lighter weight. In some cases you will have to use a combination of heavy weights for greater strength and lighter weights for more explosive power or speed.
If you are involved in a sport that requires muscular endurance, as for example, in running long distances or team sports such as soccer, field hockey and lacrosse, you will need considerable muscular endurance of the leg muscles (in addition to cardiovascular endurance). Thus, your exercises should be devoted to higher repetitions with light weight for more muscular endurance, especially local muscular endurance.
As mentioned above a critical factor that must be addressed at all times is form. This means how the exercises are executed–in other words, exercise technique. The more weight you use, the more there is a tendency to change technique. Thus, the amount of weight that you use must be determined by how effectively you can still do the exercise.
Merely handling more weight but with a disruption in how the exercise is done, can bring about significantly different results, if not injury. This is especially true for athletes as it affects coordination which in turn affects game skills. Exercise technique is also critical, when doing specialized strength exercises that duplicate the muscle action taking place during the skill
For related information, see Biomechanics and Kinesiology of Exercise and The Revolutionary 1 x 20RM Strength Training Program.