AMRAP With Friends

5 minute AMRAP

The Iron Pendulum

Core under fatigue · Midline Tension · intensity 3 of 5

The workout

As many rounds as possible in 5 minutes of:

Overview

The Iron Pendulum is 12 skater jumps and 20 russian twists. The work moves through the quads and the obliques instead of sitting on one muscle.

Muscles worked

Energy systems

These are overlapping contributions. This workout is not assigned to one energy system.

  • Glycolytic: Moderate
  • Oxidative: Moderate
  • Neuromuscular: Moderate

Training effect

Immediate demand

5 minutes, intensity 3 of 5. Today the limiter is the russian twists.

Intended stimulus

The style is built so a trunk position has to survive the moving reps. On this workout that is 12 skater jumps and 20 russian twists.

Repeated practice

Repeat the same workout and compare the score. What can change over weeks is how long that pace lasts. One time through does not produce that change.

Body-composition context

Body weight changes with the rest of how you eat and train. This workout is one piece of work on one day.

Expected feel

20 russian twists is where the round gets hard. The other movements still have to be finished after it.

Pacing

Rotational stability under fire. Touch both hands to the floor outside the hip on every single twist.

Keep each round about the same length. Do not drop the russian twists to keep the other sets moving.

The movements

Skater Jumps

Keep the chest up. Looking down at the floor rounds the back and cuts off your airway.

What not to do. Bounding forward instead of laterally, so the hips never load sideways.

Russian Twists

Cross your ankles to lock the lower body and isolate the rotation to the thoracic spine.

What not to do. Swinging the arms across the body while the shoulders stay square.

Why these movements

The work moves through the quads and the obliques instead of sitting on one muscle.

Scaling

Keep a brace or a hollow position in every round. Drop the moving reps before you drop the position that makes the trunk work.

Skater Jumps

  • Step instead of jump. Same pattern, same range, no flight. Keeps the pace without the landing.
  • Lower and slower. Keep the jump but cut the height and take the landing softly.

Russian Twists

  • Knees bent. Bend the knees to shorten the lever. The shorter it is, the lighter it is.
  • Partial range. Move only through the range where you can keep the lower back on the floor.

Mistakes and who it is for

  • Opening the skater jumps at a sprint makes the russian twists the piece that falls apart.
  • Resting until you feel fresh between movements removes the point of keeping them in one round.
  • Letting the russian twists shrink so the rest of the round can speed up changes the workout on the page.

Suited to someone who wants 5 minutes through Skater Jumps, Russian Twists.

Scoring and progression

Work through the movements in the order listed, then start the next round. Your score is the number of complete rounds plus any reps of the round you were partway through when the clock hit zero — written as rounds plus reps, so seven full rounds and twelve reps is7+12.

Progression is repeating this workout and comparing that score. The page does not promise a change from one time through.

Related workouts

Run it with friends

The Iron Pendulum runs on a shared countdown: share a rally link, everyone gets the same 5-minute clock, and the leaderboard updates as people log rounds.