Flexion Leg Sit-up (Straight Arm, Single Leg)
Intermediate
Expert Advice
Touching your toes is optional. Shorten the rise if reaching farther requires swinging your arms or bending the working knee.
How-to-do Steps
- Lie on your back with one leg extended and the opposite foot planted, knee bent.
- Extend both arms overhead along the floor, keeping your elbows straight.
- Exhale as you raise your trunk and extended leg together.
- Reach both hands toward the raised foot without lifting your supporting foot.
- Lower your trunk, arms, and working leg back to the floor with control.
- Complete the prescribed reps on this side, then switch legs and repeat.
Common Mistakes
- Torso twists toward the raised legFix: keep both shoulders facing forward.
- Chin presses into your chestFix: leave a small gap beneath your chin.
Coach Cues
Lift togetherSupporting foot stays plantedReach without twisting
Short reminders to keep in mind during every set.
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Muscles Worked
Flexion Leg Sit-up (Straight Arm, Single Leg) primarily targets the Abs, Quads, with Strength mechanics using Body Weight. Understanding muscle activation patterns helps you focus on proper engagement and maximize training effectiveness.
Primary
Abs60%
Quads40%
Equipment
Body Weight
Exercise Type
Strength
Why Level 3?
Intermediate
Coordinating a full sit-up with a straight-leg raise requires abdominal strength and control.
Technique
Stability
Strength
Mobility
Impact
Learning
Sets & Reps Guidance
Beginner3 x 10-12
Intermediate4 x 8-10
Advanced4 x 6-8
Variations
Easier Variation
Frequently Asked Questions
What muscles does Flexion Leg Sit-up (Straight Arm, Single Leg) work?
Flexion Leg Sit-up (Straight Arm, Single Leg) primarily targets the Abs, Quads. It is classified as a Strength exercise performed with Body Weight.
How many sets and reps should I do for Flexion Leg Sit-up (Straight Arm, Single Leg)?
For beginners, start with 3 sets of 10-12. Intermediate lifters can do 4 sets of 8-10. Advanced athletes can push to 4 sets of 6-8. Adjust based on your goals and recovery capacity.
Is Flexion Leg Sit-up (Straight Arm, Single Leg) suitable for beginners?
Flexion Leg Sit-up (Straight Arm, Single Leg) is rated as intermediate difficulty. Beginners may want to start with lighter loads or simpler variations and progress to this exercise as their strength and coordination improve.
What are the most common mistakes when doing Flexion Leg Sit-up (Straight Arm, Single Leg)?
Torso twists toward the raised leg: keep both shoulders facing forward. Chin presses into your chest: leave a small gap beneath your chin.
