🛑 Stop confusing abs and hip flexors! 👇
1️⃣ CRUNCH (REAL ABS WORK)
✅ TARGET: Rectus abdominis (95%), Obliques (60%)
🔹 FORM:
• Shoulder blades only lift off floor
• Lower back stays glued to ground
• Chin to chest (no neck pull)
💡 PRO TIP:
“Exhale sharply at top → fire those abs!”
2️⃣ SIT-UP (HIP FLEXOR DOMINANT)
✅ TARGET: Iliopsoas (85%), Rectus femoris (70%)
🔹 FORM:
• Full torso lift → hips flex
• Feet often anchored → leverages hip flexors
💡 PRO TIP:
“Sit up FAST, lower SLOW → protects spine”
⚡️Muscle Activation⚡️
Crunch:
— Upper Abs: 💥💥💥💥💥
— Lower Abs: 💥💥💥
— Hip Flexors: 💥
— Obliques: 💥💥💥💥
Sit-Up:
— Upper Abs: 💥💥
— Lower Abs: 💥
— Hip Flexors: 💥💥💥💥💥
— Obliques: 💥💥
(EMG data: Contreras, 2021)
❗ WHY BOTH MATTER:
▫️ CRUNCHES ARE BETTER FOR:
• Isolating abs without hip flexor compensation
• Spinal safety (no lumbar strain)
• Post-rehab training
▫️ SIT-UPS ARE BETTER FOR:
• Maintaining hip flexor mobility (combats “sitting disease”)
• Functional movements (getting up from bed/floor)
• Athletic power (sprinting, kicking)
⚠️ COMMON MYTH DEBUNKED:
“Sit-ups give you six-pack abs” → FALSE!
They primarily train hip flexors, not abs. For visible abs:
→ Do crunches + reverse crunches
→ Reduce body fat (less 15% for men, less 22% for women)
⚡️ PRO TRAINING TIPS:
For office workers:
• 3x/week sit-ups → combat hip tightness
• Follow with couch stretch (30 sec/side)
For six-pack seekers:
• 4×15 crunches → slow tempo
• Add weight once mastered
❗Avoid:
• Sit-ups with straight legs → doubles lumbar stress
• Yanking neck → use abs to lift!
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👉These and other vector animated exercises for your fitness app, website or other project can be found at the link in bio
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