Repetition Types in Exercise
Repetitions are the number of actual full-ranged movements in a set. From point of exertion back to resting point the number of repetitions are key elements to muscular development. Whether it be for projected power, size, endurance, speed and explosive movement, the number of reps in a set determine these traits. The amount of weight and the duration of time to carry out these sets is also relative to the amount of repetitions achieved.
There are various repetition schemes out their and not all sports have the same. For instance, a secretary wouldn't necessarily do the same scheme as a powerlifter.
In general the more weight with fewer reps (4-6) in each weight are for power as needed in football and powerlifting. Explosive movement is also included normally for such movement in these sports. It is important to include this explosive movement for muscle recruitment forming the correct hybridizations.
A soccer player, swimmer and runner are probably looking for a lot of endurance in order to go the distance and longer lengths of time. A marathon athlete, triathlete, or mma fighter are similar. Size creates more heat in the muscles which in turn causes quicker fatigue. These physiques would look for higher repititions such as (13-15). The lawyer or secretary may look for this scheme depending on his/her goal. If they were looking for size then they would change the number of reps.
A carpentar may look for size as a client who was obese wanting "to turn the fat into muscle"-size meaning actual muscle size. A 7-12 repetition scheme is directed mainly for muscle growth with regard to size.
Doing resistance training versus one's own body weight (calesthenics) also plays role to flexibility. A fighter doesn't want to do so much weight, because it inhibits flexibility. He/she would want to do more calesthenics and cardiovascular training.
Granted in any sport or training scheme it is imperative to switch it up periodically to cause more training effects. A football player may do one or two weeks of calesthenics and come back to weights, finding out they can actually do more weight after switching it up.
Calesthenics provide more ranges of movement/motion and utilize more muscle groups then weights. Weights should still be incorporated to a degree though. Cable/machine/flex weights are somewhat limited in ranges of motion although each have there own unique characteristics. Barbells allow more free movement then machines. And dumbells allow even greater movement.
Repetition schemes are important for one's target.