Because weak ones cause more problems than people realise. Usually it's not that the core is doing nothing, it's that the outer abs are doing all the work while the deeper muscles that actually control your pelvis stay switched off.

That imbalance shows up constantly in lower back pain: poor pelvis control, an anterior tilt, a sway back, all feeding straight into back issues. It also affects how well your lower body moves generally, your running pattern, your lifting pattern, all of it. That's why almost every lower body rehab program I run has a core component built in.

No. Sit-ups train one muscle in isolation. Real core stability needs the whole corset working together, front and back, plus the pelvic floor doing its job as a hammock underneath it all.

Strength is only part of it. If your pelvis is tilting forward because something else is tight (usually the front of the thigh) no number of sit-ups will fix that. You need to address the whole system, not just one muscle.

Start by working out where you're actually at, a health professional can help with this. Train above your level and you'll aggravate things; train below it and you won't get anywhere. Either way wastes time.

The right starting point is activating the deep transverse abdominals first, then gradually adding complexity. Watch that you're not just bracing hard with the outer abs as that can actually switch off the deeper muscles you're trying to train. A Posture Pro Dome is a great tool for this.

It also helps to release tightness that's tilting your pelvis forward, since that position loads up your lower back. So:

• Release ITB tightness with a Foam Roller or Footeez Roller
  
• Trigger TFL and Glute Med with a Pocket Physio MAX or Rocket
  
• Improve thoracic mobility with the Dome or a Posture Pro roller
  

Build all of that into a regular core program and you'll see real change in your lower back pain.

You'll know it when it happens, a sharp, stabbing pain at the exact moment of injury. It's usually from an explosive movement where the abs are working hard to control the body, think heavy weightlifting or a scrum in football.

The giveaways are pain when you cough, sneeze, or try to sit up from lying down. Get this properly checked though. It's important to rule out an inguinal hernia, sports hernia, or osteitis pubis, since these can feel similar but need different management.

It's also common to see these alongside other injuries like a hip pointer from a direct knock to the iliac crest, or rib cartilage irritation, both of which can leave the abs sore and tight too.

If it's milder and came on gradually rather than from a single moment, you're probably just dealing with DOMS, common after ramping up ab work too fast, especially coming off a period of inactivity.

For a minor strain, managed well, you're usually looking at 10-14 days. A Grade 2 or higher strain is more like 4-6 weeks.

If it turns out to be a hernia or osteitis pubis rather than a straightforward strain, expect a longer road. These often need more than just rehab to resolve properly.