Muscle Contractions

Imagine yourself in the gym squatting. Not just that, you have to lower the weight down for 3 seconds, pause for 3 sec on the bottom, try to explode out of the hole, and then pause at the top for 1 sec.

We call that a 33X1 tempo. Each character corresponds to a specific task our muscles are performing. Tempos use muscle contractions to elicit a better training effect.

There are 3 types of muscles contractions, and we use them all when we're navigating life and training.

Concentric

When the muscles shorten under load. Standing up from a squat or pushing from the bottom of a push up. For a dumbbell row, the concentric contraction happens as you bring the DB towards your torso, since the muscles are shortening to get it there.

Eccentric

When the muscles are lengthening under load. Lowering portion of squat, bringing a barbell down to your chest on a bench press, and lowering a pull up are all eccentric contractions. We're typically stronger during the eccentric phase than concentric. If you've ever gotten pinned by a bench press after lowering the bar down, but just didn't have any juice to get it up, that's why.

Isometric

During an isometric contraction the force produced by the muscles is equal to the load, so nothing moves. Iso holds work on strength in a specific range of motion and stability.

Back to our 33X1 squat example.

The first number is the eccentric portion. Three sec to lower. This allows us to build in more time under load. Since you're stronger with eccentric contractions, we can drag them out to promote muscle growth and strength adaptations.

The next 3 sec is an isometric hold. After lowering the weight, you'll pause, maintaining that contraction for 3 sec. This gives you a chance to work on range of motion by maintaining proper position on the bottom and will further challenge your strength.

The X part is our concentric contraction. During this muscle shortening phase, we want to try to move as explosively as possible. This will ensure we are recruiting many muscle fibers, and therefore will reinforce strength gains.

The final number is simply an isometric hold at the top portion of the lift. It's rare this number is more than a 1.

Justin Miner

@justinminergain