Weighted or Bodyweight Sit-Up

Default prescription & biomechanics

Primary muscles

Abs

Secondary muscles

Obliques, Quadriceps

Equipment

Bodyweight

Movement pattern

Core (Pull force)

Difficulty

Beginner

Working rep range

15-25 reps per set

Between-set interval

45 seconds rest

Intensity & MET

Moderate (5.2 MET)

Step-by-step coaching cues

1. Draw your navel in towards your spine to create rigid intra-abdominal pressure and protect your lower back.
2. Perform the contraction smoothly by shortening the distance between your ribs and your pelvis.
3. Hold the peak contraction for 2 full seconds while maintaining continuous breathing.
4. Return under strict eccentric control without using momentum or pulling on your neck.

Joint & safety considerations

Filtered for Lower Back sensitivity. When you flag lower back sensitivity in your WorkoutCard training brief, the AI programme generator automatically substitutes a lower-stress alternative from the relations table below.

Biomechanical alternatives & swaps

Used by the in-app Swap sheet when your equipment is occupied or when adjusting exercise difficulty.

Exercise	Relationship	Equipment
Kneeling Rope Cable Crunch	Cable swap	Cable
Bench or Floor Reverse Crunch	Same movement pattern	Bodyweight
Controlled Contralateral Dead Bug	Same movement pattern	Bodyweight
Floor or Decline Crunch	Same movement pattern	Bodyweight
Gymnastic Hollow Body Hold	Same movement pattern	Bodyweight
Hardstyle RKC Plank	Same movement pattern	Bodyweight

From the WorkoutCard biomechanical library (613 verified movements). For general strength and conditioning education, not medical or physiotherapy advice.