Question

How are repetitions related to weight training for endurance?

Answer 1

Weight training intensity basically refers to how much weight you will be lifting and how heavy or light that weight is for you on a given exercise.

The lighter the weight/easier it is for you, the lower the intensity. The heavier the weight/harder it is for you, the higher the intensity.

And, all of this intensity stuff is usually predicted by one thing: how many reps you’re doing per set.

Reps (short for “repetitions”) are the number of times you move a weight from point A to point B during a set of an exercise. The lighter the weight, the more reps you will be able to lift it for. The heavier the weight, the fewer reps you’ll be able to lift it for.

Obvious, I know. But, as you can see, reps and intensity go hand in hand most of the time. Meaning…

The more reps you can lift a weight for = the lower your training intensity is.
The fewer reps you can lift a weight for = the higher your training intensity is.
The reason this is important to us is because certain levels of intensity are more ideal for certain goals than others (due to factors like time under tension, muscle fiber recruitment, etc.).

And this leads to an important question: what weight training intensity is best for your goal?

Or, to put it another way, how many reps should you do per set of an exercise? Let’s find out…

Answer 2

The lighter the weight, the more reps you will be able to lift it for. The heavier the weight, the fewer reps you'll be able to lift it for. Obvious, I know.

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So, as you can see:

Lower reps (high intensity) is most ideal for increasing strength.

Higher reps (low intensity) is most ideal for improving muscle endurance.