5 minute AMRAP
Core Melt
Local muscle burn · Localized Trap · intensity 3 of 5
The workout
As many rounds as possible in 5 minutes of:
- 10 V-Ups
- 15 Butterfly Sit-ups
- 15s Hollow Hold
Overview
Core Melt is 10 v-ups, 15 butterfly sit-ups, then a 15-second hollow hold. Every piece stays on the midline, and the hollow hold is where the round closes. Later rounds slow because the work never leaves the midline.
Muscles worked
Midline
V-Ups, Butterfly Sit-ups, Hollow Hold
Energy systems
These are overlapping contributions. This workout is not assigned to one energy system.
This workout departs from its style on the profile below.
- Glycolytic: High
- Oxidative: Low
- Neuromuscular: High
Training effect
Immediate demand
5 minutes, intensity 3 of 5. Today the limiter is the midline, closed by the hollow hold.
Intended stimulus
The style is built to tire one region before breathing is what stops the round. On this workout that is 10 v-ups, 15 butterfly sit-ups, then a 15-second hollow hold.
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
Later rounds slow because the work never leaves the midline.
Pacing
The hollow hold must be strictly enforced: lower back pinned violently to the floor.
Build across the clock. Do not open the v-ups so hard that the later sets shrink. Keep the hollow hold the full 15 seconds even if the other sets break. Do not rest the midline back to fresh between rounds.
The movements
V-Ups
If you bend your knees to reach your toes, you are cheating the lower abdominals.
What not to do. Bending the knees to bring the feet closer to the hands.
Butterfly Sit-ups
The butterfly leg position mechanically disables the hip flexors, forcing pure abdominal contraction. Do not use your arms to swing forward.
What not to do. Letting the knees rise off the floor to help the torso up.
Hollow Hold
Fatigue causes the back to arch. Regress the movement immediately by tucking your knees toward your chest when this happens.
What not to do. Letting the lower back arch away from the floor as the legs tire.
Why these movements
Every piece stays on the midline, and the hollow hold is where the round closes. Later rounds slow because the work never leaves the midline.
Scaling
Keep the work on the same muscle region. Drop reps on the hardest movement before you swap in a different pattern.
V-Ups
- 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.
Butterfly Sit-ups
- 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.
Hollow Hold
- 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 v-ups at a sprint makes the hollow hold the piece that falls apart.
- Resting the midline back to fresh between rounds turns this into a different workout.
- Letting the hollow hold shrink so the rest of the round can speed up changes the workout on the page.
Suited to someone who wants 5 minutes on the midline and can already do V-Ups, Butterfly Sit-ups, Hollow Hold.
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
- The Arch
Same hold, different moving piece
- Active Sonar
Same midline, longer clock
- Symmetry
Same midline, longer clock
Run it with friends
Core Melt runs on a shared countdown: share a rally link, everyone gets the same 5-minute clock, and the leaderboard updates as people log rounds.