Newsletter Sign Up

Wednesday, April 13, 2011

Workout Wednesday - Are Situps Bad For You?

This is a very controversial subject in the fitness community. There are many that will tell you that situps are bad for your back. That crunches are a better option. That performing crunches on a Bosu ball or stability ball will help protect your back.

In his book Low Back Disorders Dr. Stuart McGill states that "traditional sit-ups cause spine loading conditions that greatly elevate the risk of injury". He also states that "the traditional sit-up imposes approximately 3300N (about 730lb) of compression on the spine... The National Institute for Occupational Safety and Health has set the action limit for low back compression at 3300N; repetitive loading above this level is linked with higher injury rates in workers."

So lets see if we can make some sense of all this.

Are crunches a better option? When performing a crunch you lay flat on your back and flex your trunk. This contracts your rectus abdominis. Training your abdominal muscles in this way does not make any sense. Your rectus abdominis is broken into separate "sections". It is designed this way to be a stabilizer, not a spinal flexor. If the rectus abdominis was meant to be solely a spinal flexor then it would be a hamstring (one long muscle, like your leg muscles). This would be a much more efficient force producer.

Crunches also lack the ability to train the transverse abdominus, oblique, and spinal erector muscle groups. If you look at the way these muscles are designed, it is pretty easy to see that the function of these muscles is to support the spine when working in unison. So why not train all these muscle groups at the same time?

Another issue with the crunch: When performing a crunch, you are training spinal flexion. Specifically lumbar (lower back) spinal flexion. The lumbar spine is built for stability, not mobility. It does not make sense to train it in a mobile manner.

My Conclusion on the Crunch: I'm not a fan of the crunch. Have you ever performed a crunch in your every day life in order to complete a task? I haven't. The crunch is not an efficient exercise, nor is it a natural movement.

Are crunches on a Bosu or stability ball better? I'm going to keep this one short. I've already stated that I am not a fan of the crunch. It is not a movement that is natural or efficient. Performing the movement on a ball does not make it any more natural or efficient. It just makes you look silly.

Loads on the Spine During the Situp: 3300N (730lb) of compressive load during a standard situp. This is definitely a concern. It is easy to say "wow, that's a lot! Better not do situps because I don't want to hurt my back." BUT, we have to keep a couple things in mind.

  1. A tissue will adapt to the loads we place upon it. This is the whole idea when we weight train. We start out barely able to perform a pushup. We progressively add resistance over time and our tissues (muscles, bones, ligaments, tendons) adapt and become stronger. Over time we are able to knock out multiple pushups with added resistance! The tissues in our "core" are the same way.
  2. Do we want to "protect" the spine? We definitely want to make the spine, and the muscles surrounding the spine, stronger. Making it stronger is the best way to "protect" the spine. In order to do this we must train it, not stay away from it!
  3. I cannot overstate how important common sense is! Are you going to knock out 50 situps if you have a herniated disk? I HOPE NOT! Just like you wouldn't try to knock out 50 pushups with a torn rotator cuff!
"But Mike, didn't you say the lumbar spine shouldn't be trained in a flexed state? Don't you flex your spine during a situp?" Good question! Some people do flex their spine a lot during a situp, but they shouldn't! There should be minimal flexion in the lumbar spine during a situp.

A situp should not look like this...

Notice the flexion in the lumbar spine.

A situp should look more like this...

Notice the minimal to no flexion in the lumbar spine.

I believe the situp is a very useful training tool. Is it for everybody? NO! At least not for all beginners. I believe everybody should try to build up their strength so they can perform a full situp. Think about all the times during your day that you perform a situp. I do one every time I get off the couch! It is a very natural movement. It is the way human beings get up!

But we must use common sense when training this movement, or any movement for that matter! Make sure to train with proper progression! If you are new to a movement, do NOT start knocking out 50-100 reps daily. Start slowly and get proper recovery time!

What do you think of the situp? Do you think they are safe? Do you think they are a good training tool?


Related Posts Plugin for WordPress, Blogger...