I don’t know if you have ever been worried why “sit ups” was literally everywhere? I don’ know what is the f…… reason “sit ups” has become one of the most popular and common exercises in almost every single gym/fitness center or sports field anywhere.
Just 10 years ago (approx.) people started to think that “sit up” exercise maybe has more bad than good sides. But still I don’t understand the reason – because anatomy and biomechanics sciences are enough old and evidences were everywhere. Plus this exercise is not “specific” to any sport, people figured out that core stabilization exercises (in standing position mainly) are almost everything athletes need when it comes to FUNCTIONAL core strengthening (through pallof press, landmine variations…). Because the core is probably more of a force transmitter than a force producer (especially with throwers). If an athlete doesn’t have a strong core he/she will have a problem with proper strength, speed, agility, power, quickness…
Oh, I think I know what is the reason for “sit ups” popularity (with various weights on the chest mainly), SIX PACKS of course! Serious six packs start to occur with concentric and ecc. muscle actions (not ISO), this is the reason why “sit ups” and any similar exercise has gained popularity. Maybe one more reason exists – most people are lazy to come up with something new and/or like to rewrite exercises (“if everyone do it – must be good” philosophy needs reviewing).
Everything started with bodybuilders and their methods for sure. Today’s modern abs training among athletes is looking just for strong and stable core muscles (core is everything from neck to thighs), who cares for six packs (ok almost everyone care but it’s totally nonfunctional and at first glance seems healthy, but it’s not at all). What is actually problem with “sit ups”?
In short, “sit ups” include raising lower back from the floor and the main issue occurs here. For example, during crunch (or crunch with raised legs – even better for posterior pelvic tilt) thoracic spine flexion occurs only – which is not bad because T spine mobility is definitely something you need – even in sagittal plane which is not recommended to kyphotic people too much without opposite movement. But more important is that your lower back stays flat on the ground. Better slight flexion than too much flexion with “sit ups” (maybe the best is if you put a small rolled towel below the lower back curve – truly neutral position when doing crunch/crunch with raised legs). Flat lower back occurs in mentioned exercise(s) because your legs are bent with crunch, or raised at 90hip-90knee with crunch with raised legs and it’s relaxing – posterior pelvic tilt – position for lower back.
Those mentioned exercises are 1st progression of course, if you want some serious “six packs” you need next progressions…
Ok, when you are raising lower back from the floor a really bad forces occur down there at the spine (not vertical forces too much but horizontal for sure). Abdominal muscles pull lower back to, for the lower back intervertebral discs uncomfortable, excessive flexion and that could be a trigger for disc pinching and other damaging after a ton of reps. If you do “sit ups” faster and with more weights on the chest an issue becomes even worse! Or lying with fully extended legs (variation) – m. iliopsoas pulls more in the beginning (making greater intervertebral compression).
YOUR INTERVERTEBRAL DISCS CAN “EXPLODE” IF YOU ARE DOING ALMOST THE ONLY ONE WORSE FOR LOWER BACK EXERCISE THAN “SIT UPS” – “SIT UPS WITH TWISTING”!
Of course, this exercise will not “kill” you because there is no external load but why risk some microtraumas which can lead to some serious acute or chronic desease, especially if you do the exercise fast…
Sit ups with twisting is something you should definitely avoid because you need a serious physical analysis when it comes to revealing all kinds of bad forces attacking your lower back. Of course, as the speed and weights raise – the injury risk raise.
You can do twisting with flat back (neutral spine) up to 45 angle torso – sitting position (I said up to 45 angle torso because lever drives exercise harder and m. iliopsoas is “more off” than with torso-pelvis above 45 – advice for advanced athletes) and with feet stuck in (with nonmoving feet you are more STABLE because there is no disturbing feet lifting movements – at “lower back in the air” position hip flexors are starting to be active and tend to move feet up because they are the link between pelvis/lower back and legs and naturally want to move both ends toward each other – if there is the feet supports nothing will disturb the proper execution). Otherwise, torso lever arm is longer (it means more effort for muscles) as it’s closer to the ground (torso) – beginners should start from 45 angle torso. This is a much better (but not easy) option because you will make twists only at T spine but not at lower back which should stay neutral and faced forward at same place non-stop (abs should work on isometric way – because of torso angle – which is the main goal when it comes to proper abs strengthening, compared with obliques – they need more dynamic strength because twisting movement is a MUCH MORE present than torso bending in sport and life in general). If you notice that your lower ribs move well that’s everything important you need (that’s mean that obliques work on a proper way – which is the goal while twisting). Ok, you need also isometric strengthening of obliques (a ton of examples in sports practice) but twisting is also important in terms of agility, a proper moving and similar.
Remember, your lower back should stay in “neutral” position while doing ANY exercise!
Thanks for reading and all the best,