Definition
The core is the entire midsection — rectus abdominis (six-pack), obliques (sides), transverse abdominis (deep stabilizer), erector spinae (lower back), and the diaphragm. Its primary job is to resist movement (anti-extension, anti-rotation, anti-lateral flexion) so the spine stays neutral under load.
Real questions
Are crunches the best core exercise?
No. Heavy compound lifts (squats, deadlifts, overhead press) train the core hardest. Add 1–2 anti-extension/anti-rotation exercises (planks, dead bugs, Pallof press) for full coverage.
How often should I train abs?
2–4 short sessions per week of 10–15 minutes is plenty if you're also lifting heavy.
Stack with
Put it to work
Coach Foster builds your program around core and the rest of the fundamentals, shaped to your body and your week.