15 minute AMRAP
Aerobic Threshold
Cardio capacity · Engine Room · intensity 3 of 5
The workout
As many rounds as possible in 15 minutes of:
Overview
Aerobic Threshold is 12 sprawls, 24 air squats, and 24 lateral line hops. The work moves through the full body and the quads instead of sitting on one muscle.
Muscles worked
Full body
Glutes
Quads
Energy systems
These are overlapping contributions. This workout is not assigned to one energy system.
- Glycolytic: Low
- Oxidative: High
- Neuromuscular: Low
Training effect
Immediate demand
15 minutes, intensity 3 of 5. Today the limiter is the sets being the same size.
Intended stimulus
The same capacity work, with movements you can repeat for the whole clock. On this workout that is 12 sprawls, 24 air squats, and 24 lateral line hops.
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
The sets are the same size. The round gets hard when one of them breaks.
Pacing
A high-turnover piston. Keep the line hops incredibly low to the ground to save the calves.
Keep the later rounds moving at the same size as the early ones. Do not drop the sprawls to keep the other sets moving.
The movements
Sprawls (Standard)
Keep a wide stance. Landing with your feet outside your hands reduces the distance your hips have to travel and speeds up the transition to standing.
What not to do. Landing the plank with the hips high instead of level with the shoulders.
Air Squats
Let gravity do the work on the way down. Pull yourself into the bottom quickly, then explode up. Use your arms for rhythm.
What not to do. Cutting the depth once the legs burn, so the hip crease stops above the knee.
Lateral Line Hops
Keep your eyes up. Looking down at the line naturally rounds the shoulders and constricts the airway.
What not to do. Letting the feet come apart in the air and landing one at a time.
Why these movements
The work moves through the full body and the quads instead of sitting on one muscle.
Scaling
Keep the round short enough to repeat. Drop reps so you can stay moving, rather than resting the round into a different workout.
Sprawls (Standard)
- Step the feet. Step back and step in instead of jumping. Same shape, no impact.
- Hands elevated. Hands on a bench or step so the floor never comes all the way up to you.
- No jump at the top. Stand tall and reach instead of leaving the floor.
Air Squats
- To a seat. Squat to a chair or box and stand back up. Lower the seat as you improve.
- Hold a support. Hands on a doorframe or chair back to sit deeper than balance allows alone.
- Shorter range. Go only as deep as you can control, and stop before the heels lift.
Lateral Line Hops
- 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.
Mistakes and who it is for
- Opening the sprawls at a sprint makes the sprawls the piece that falls apart.
- Resting until you feel fresh between movements removes the point of keeping them in one round.
- Spending the first minutes hard leaves the later rounds as a different, slower workout.
Suited to someone who wants 15 minutes through Sprawls (Standard), Air Squats, Lateral Line Hops.
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
- Posterior Vanguard
Same quads, longer clock
- The Cruiser
Same quads, shorter clock
- The Endurance Engine
Same quads, longer clock
Run it with friends
Aerobic Threshold runs on a shared countdown: share a rally link, everyone gets the same 15-minute clock, and the leaderboard updates as people log rounds.