Thoughts about Crossfit, the Denominator Effect

Every year, as a member for the editorial board for the American College of Sports Medicine's Health & Fitness journal, we are asked to fill out a survey about trends in fitness.  One of the questions was on a scale of 1-10, how "hot" a trend is Crossfit.  I said Crossfit clearly is a 10.

Like many health care practitioners, I often get a skewed perspective of new fitness trends, since I primarily see patients when they get injured.  Inevitably, as new fitness trends emerge, I will start seeing a corresponding increase in injuries.  A decade ago, I started seeing yoga injuries, followed by Zumba injuries, followed by P90X injuries, and more recently Crossfit injuries.

I think it's essential to keep in mind what I call the "Denominator Effect."  What is relevant is not the total number of injuries, but rather how many injuries I am seeing, divided by the number of people participating in that activity.  Of course, as something gains in popularity, the number of injuries will go up, but I need to know the rate of injury increase.  The other major factor- for those who are NOT injured, how much benefit are they seeing.

Let me cut to chase before going into detail- I really like Crossfit.

For those not familiar with Crossfit, it is a form of high intensity training.  High intensity training is, for those who are physically ready to handle it, arguably the single best form of exercise one can perform.  The American College of Sports Medicine recommends aerobic conditioning, strength training, balance training, flexibility training, and a training plan as part of their exercise prescription, and Crossfit is a convenient way to hit all of those exercise goals.

The typical Crossfit workout starts with a well designed warm up for 5-10 minutes, followed by 15-20 minutes of weight training (focused on classic Olympic lifts or power-lifting techniques), followed by 15-20 minutes of the "Workout of the Day" (called the "WOD" in Crossfit parlance), followed by a cool down/ stretch.

The Workout of the Day often combines different calisthenic movements for time.  For example, it may include a 200 meter sprint, followed by kettle bell swings, followed by pull-ups, then repeated, with the goal of finishing as quickly as possible.

I can't speak definitively about all Crossfits, but I have had a very positive experience at Sasquatch Crossfit in Redmond, Washington- http://sasquatchcrossfit.com/index.html.

Things I liked about the Crossfit experience:

1. Attentive care: The trainers sincerely cared about their team, and focused on creating a positive experience.  I consider myself in reasonably good shape, but I had some major deficits that needed to be addressed, particularly horrible kinesthetic awareness and hip range of motion.  I was concerned about my poor form causing an injury, but the trainers took time to work with me to enhance my form, and encouraged me to perform more simple motions so that I could develop proper range.

2. Focus on full range of motion.  One of the things that the Crossfit experience taught me was the benefit of exercising through full range.  Prior to training with Crossfit, I would encourage patients (and myself) to limit themselves through shorter arcs of motion, like half squats instead of full squats.  I was wrong.  I found that by practicing full range of motion, I dramatically improved strength in the ranges I had not previously challenged.  Perhaps more importantly, my flexibility and functional range of motion dramatically improved.

3. Supportive environment.  The team philosophy is very strong.  At Saquatch CrossFit, the owner Tim is one of the trainers, and having worked with all 4 trainers, there was a consistent quality and philosophy across the trainers.  I remember doing one particularly grueling exercise (repeated lunges with a barbell), and having Tim cheer me on from the finish line and another trainer, Everett, walk next to me to correct form and provide motivation was inspiring.  While it's theoretically possible I would be able to maintain that level of intensity on my own, but realistically I don't think I have the level of pure intrinsic motivation, and the coaches really helped in making me feel like I was part of something bigger than myself.

So those are the pros.  What are the cons?
1. Not for everyone.  The workouts are challenging, so people with low baseline levels of fitness will struggle.  I routinely found my heart rate within 80-99% of my maximum, so if you have cardiac issues, I would discuss this with your physician before starting Crossfit.  If you have musculoskeletal conditions, seeing a Board Certified Sports Medicine specialist familiar with Crossfit (..... like, of course, Garrett Hyman and I at Lake Washington Sports & Spine) can help figure out how to participate safely.
2. Knowing your limits.  With some of the exercises, it can be tempting to lift as heavy as you can.  It is much more important to focus on proper form.  In fairness to all the trainers I worked with at Crossfit, they were very attentive to this issue, but I suspect some people may be tempted to lift heavy before they learn proper form and expose themselves to injury risk.  I am a beginner, so I know I can lift heavier with bad form, but that's not my goal.
3. Inherent risks with high intensity training.  All forms of high intensity training have increased risk, so I think when assessing the risk of training for Crossfit, it really needs to be compared to other high intensity modalities like Martial Arts training, Zumba, P90X, etc.  Reviewing the scientific literature, I have seen evidence for the benefits of Crossfit (e.g., http://www.ncbi.nlm.nih.gov/pubmed/23439334), but I have not seen data on the injury rate.  In my personal opinion, I think the risk is probably on the lower end of high intensity training modalities IF you listen to your trainers.  Compared to martial arts training, you don't have as high a risk of someone else injuring you, and compared to P90X, you have supervision to assess your form.
4.Deterioration of form with fatigue.  Crossfit is tiring, so it's especially important to be attentive to form as you tire yourself out.
5. Specific areas for potential injury- all can be prevented with focus on form.
    A. The low back.  Any type of loaded flexion with twisting movements can expose the back, particularly the disks, to injury.  The back is particularly vulnerable during kettle bell swings.
    B. Knees/Hips.  You are generating  force through the "kinetic chain," so if the forces are not transmitted smoothly with proper form, both knees and hips can be injured.
    C. Shoulders: As with the knees and hips, the shoulders are the base for the kinetic chain in the upper body, and therefore care must be made to transmit forces with proper form.

Overall Thoughts and Feedback for Patients:
1. Crossfit, when done with proper form under the guidance of good trainers, can be a complete package in terms of meeting the American College of Sports Medicine's recommendations for exercise.
2. It's high intensity, so it can create better results than lower intensity exercise, but also has risk of injury inherent to all forms of high intensity exercise.
3. You need to do a realistic assessment of your capabilities, both in starting Crossfit and in advancing your loads.
4. If you are unsure of your capabilities, working with Sports Medicine physicians like those at Lake Washington Sports & Spine can help in meeting your exercise goals.

Journal Club: Effect of running and walking on osteoarthritis and hip replacement risk

The article reviewed is WILLIAMS, P. T. Effects of Running and Walking on Osteoarthritis and Hip Replacement Risk. Med. Sci. Sports Exerc., Vol. 45, No. 7, pp. 1292–1297, 2013

http://www.ncbi.nlm.nih.gov/pubmed/?term=WILLIAMS%2C+P.+T.+Effects+of+Running+and+Walking+on+Osteoarthritis+and+Hip+Replacement+Risk.+Med.+Sci.+Sports+Exerc.%2C+Vol.+45%2C+No.+7%2C+pp.+1292–1297%2C+2013
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Design:

• This well designed article evaluated 74,752 runners and 14,625 walkers from the National Runners' and Walkers' Health Studies.  This is an unusually large number of runners and walkers evaluated, which is often a limiting factor in most studies.
• The runners and walkers were queried as to whether they were ever told by a physician they hip osteoarthritis.  This is an imperfect way of assessing the development of hip osteoarthritis, but as imperfect measures go, it is reasonable.  In some ways, this is a better measure than using a more "objective" standard like criteria based on x-ray or MRI imaging, since the correlation between imaging finding and functional limitations is imperfect, and for most patients, the only reason a physician would tell them they had hip OA is because they went to the doctor regarding a functional issue.  If I had a perfect measure, I'd want some form of functional assessment, but I do think this is a reasonable proxy.
• Another outcome measure was whether they reported having a hip replacement.  This is also a reasonably good measure- I don't know for sure, but I was assume that the correlation between reporting have a hip replacement and actually having a hip replacement is very close to 1.0.  Reporting bias is always a concern, but this is a case where I suspect the effect of reporting bias is negligible.

Results:

• As people age, they are more likely to both develop hip OA and get a hip replacement.  A bit of "no duh" result, but still useful to confirm.
• This effect of age was stronger for women than it was for men.  This confirms some other research (.... I'm thinking specifically of some of the aging/mobility research by Stephanie Studenski, one of my former colleagues from Pitt- http://www.upmc.com/media/experts/pages/stephanie-a-studenski.aspx), which is that people age, men are more frequently limited by medical conditions (like heart disease), and women  are more frequently limited by musculoskeletal conditions.
• Other factors associated with increased risk of either hip OA or hip replacement included: 
• Estrogen + Progesterone usage (notably, estrogen use alone did not, nor did menstrual status)
• Years of eduction (..... I guess a downside of being an MD/PhD)
• Intake of red meat (..... just what I need to hear on the 4th of July)
• Perhaps the most important finding in this study- the risk of hip OA and hip replacement went down the more someone ran.  This is an important finding, since I know many runners are concerned that their mileage is putting them at risk for developing arthritis.  It appears the opposite is true for the hips.
• A similar effect was found for walkers.
• The risk for hip OA and replacement was increased the larger the body size, as measured by body mass index.  Most, but not all, of the benefits of running and walking appeared to be related to the associated decrease in BMI.

Bottom Line: What does this mean for our patients?

• Running is good
• One of the theoretical concerns about running too much is that it may make one more likely to develop osteoarthritis or need a hip replacement.  Per this study, at least, the opposite is true
• Amongst the many benefits of running, it helps maintain a leaner body type, and this is likely one of the mechanisms that explains the protective benefit of running
• The article goes into the biology of cartilage.  In my opinion, much of that is in the realm of speculation and not assessed in this study, so this study does not do anything to alter our knowledge in those domains.  The study is valid regardless.

Prone Press Up

This may be single favorite exercise.  It is one of the most fundamental exercises in the Mechanical Diagnosis and Therapy (McKenzie) protocol, and is very similar to the Upward Facing Dog movement in Yoga.

I always do this exercise first thing when I get to my hotel room after a long plane flight, and it's very helpful for many patients who need to centralize their radicular symptoms (please see blog post about centralization- http://lakewass.blogspot.com/2013/07/centralization.html), or to help with low back stiffness while driving or flying on airplane (http://lakewass.blogspot.com/2013/07/tips-for-flying-with-low-back-pain.html).

Technical note about the picture below: I have no idea why I am grunting so much, but that is NOT proper form.  Try to stay more relaxed and control your breathing

INSTRUCTIONS:
1. Lie on belly
2. Place hands next to shoulders like you are going to do a push-up
3. Take a deep breath in
4. As you breathe out, slowly arch your back upward
5. You may feel a point of stiffness in your low back- it is important to push through that stiffness
6. Lower yourself down so that you are completely flat again
7. Take a deep breath, and then repeat

Tips:
1. Make sure your pelvis stays on the table
2. If you have leg pain, your goal is to pull that leg pain into your back.  This may intensify your low back pain- that is ok.  This called centralizing your symptoms when you pull the pain out of your legs and into your back
3. You should feel your back start to loosen after 10-20 repetitions

When to do:
1. 20 repetitions every morning
2. 10 repetitions after any time that you have been sitting for prolonged periods (car rides, airplane flights, sitting in class)

Standing Back Extension

This is one of my favorite exercises, and I commonly recommend it to patients with low back to help centralize symptoms (please see blog post about centralization- http://lakewass.blogspot.com/2013/07/centralization.html), or to help with low back stiffness while driving or flying on airplane (http://lakewass.blogspot.com/2013/07/tips-for-flying-with-low-back-pain.html).

INSTRUCTIONS:
1. Stand with your back to a table, with the edge of the table just below your waistline
2. Make sure your feet are all the way back up against the table
3. Cross your arms in front of your chest
4. Take a deep breath in
5. As you are exhaling, arch your back backward
6. You may feel some stiffness- it is important to push through that stiffness.  Try to arch back a bit further with each repetition
7. Come back to neutral
8. Take a deep breath in
9. Repeat by arching backward as you exhale

Tips:
- Your goal is to CENTRALIZE your symptoms.  This means that you are trying to pull your symptoms away from your foot, leg, thigh, and buttock, and INTO your back.  Your back hurt more at first, but should loosen up after 10-20 repetitions

Tips for Flying with Low Back Pain

Flying is one of the toughest activities for patients with low back pain.

In some upcoming posts, I will include a few exercises you can perform on the plane, particularly standing back extensions, proximal hamstring stretches, and hip flexor stretches.

This post will focus on making sure you have sufficient lumbar support.  Most (.... and my most, I mean all) airplane seats are not designed with the low back in mind.  I suggest using a lumbar support when flying - I usually use a cylindrical roll they sell at the magazine shops, often recommended for the neck.

I often forget to bring a lumbar support with me, though, so what I then recommend is using magazines in the airplane as a makeshift lumbar support roll.  I am a big guy, so I usually need 4 magazines, which usually includes the in-flight magazine and Skymall from both myself and neighbor.

The pictures included here are intended to show you how to make the lumbar support roll.

Wall Centralization Exercise

On a previous post, we discussed centralization.  One exercise that can help with centralization is the Wall Centralization Exercise.  Often, patients benefit in performing this exercise under the guidance of a skilled Physical Therapist or Chiropractor familiar with the Mechanical Diagnosis and Therapy protocol (sometimes called McKenzie, named after the person who developed the protocol).

WALL CENTRALIZATION EXERCISE:

1. Lean against the wall with your shoulder against the wall (check with your doctor, PT, or chiropractor to make sure you are performing on the proper side)

2. Place your far foot firmly on the floor, and place your near foot (the side closer to the wall) over the planted foot, so that the near foot is not bearing any weight

3. Take a deep breath in

4. As you breathe out, slowly lean your hip into the wall

5. You may feel a point of stiffness in your low back- it is important to push through that stiffness

6. As you inhale, move back to the starting position

7. Take a deep breath, and then repeat

8. The goal for this exercise is to centralize the pain going down your leg, so that you will have less leg pain.  If this makes your back pain more intense- that is ok and expected.  After repeated repetitions, you should notice the back pain improve as well

  

Tips:

1. If you have leg pain, your goal is to pull that leg pain into your back.  This may intensify your low back pain- that is ok.  This called centralizing your symptoms when you pull the pain out of your legs and into your back

2. You should feel your back start to loosen after 10-20 repetitions

When to do:

1. 20 repetitions every morning

2. 10 repetitions after any time that you have been sitting for prolonged periods (car rides, airplane flights, sitting in class)

Centralization

CENTRALIZATION:

One approach to the management of radicular symptoms (sometimes called "sciatica") is called Mechanical Diagnosis and Therapy (MDT).  The goal of this program is to teach you how to prevent further exacerbations, and give you tools to use yourself so that if you have another exacerbation, you know how to treat it.

The key concept in an MDT program is the concept of CENTRALIZATION.

 This means that you want to pull symptoms out of your foot, leg, thigh, and buttock, and INTO your back.

- This process is called centralization because you are moving your symptoms toward the center of your body

- The goal is to move disk material away from your nerve root

- Sometimes when you perform this initially, it may actually make your back pain worse.  That is ok.  Eventually, in addition to pulling pain into your back, the goal is to make your back pain disappear.

- If the pain, instead of going into your back, goes AWAY from your back and into your buttock, thigh, leg or foot, that is called PERIPHERALIZATION.  That is not a good sign, and suggest that the disk material is pushing on your nerve root.

Sometimes, after your symptoms have improved, your therapist may work on additional strategies to help strengthen your core and prevent you from an exacerbation.

- These exercises are sometimes called LUMBAR STABILIZATION or CORE STRENGTHENING exercises.

- These are very helpful exercises. However, the concept of centralization is still the priority, because if your symptoms start to peripheralize, than means you may soon have an exacerbation of your symptoms.

- Please let your therapist or chiropractor know if you start having peripheralization, as that means you need to shift the focus back to centralization.