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Listen to Dr. Neal address this topic on Episode 185 of the podcast Optimal Health Daily.

If you can believe it, CrossFit has already been around for nearly 20 years. For those of you that may have heard of CrossFit but aren’t really sure what it’s about, I’ll briefly explain: it’s basically a form of high-intensity training. It incorporates lots of variation to help build strength and endurance, while giving you a cardiovascular workout at the same time. Many of the movements are performed dynamically and explosively and incorporate lots of compound exercises.

These are all common exercises used in CrossFit:

  • deadlifts
  • squats
  • cleans
  • box jumps
  • snatches
  • pull-ups
  • push-ups
  • shoulder presses…

Sometimes, as part of the training, you are encouraged to complete a number of sets and repetitions for time. For example, a workout may require you to complete 50 deadlifts at a weight of 135 pounds as fast as you can.

I was first exposed to this style of training a while back – actually as part of my job. Before I was full-time faculty, I was a wellness specialist for a university out here in California. My job was to help university employees feel their best. I would meet with them 1:1 and provide them with nutrition counseling, stress management tips, and so on. Even though I was a personal trainer at that time, I didn’t provide any advice when it came to physical activity. Instead, I had a colleague that worked out of our campus recreation center to whom I would refer these individuals. He was a certified personal trainer and had a degree Kinesiology, so he was well-qualified for the job. Occasionally, he and I would meet up and work out together. I would have him watch my form and we would talk about the latest research when it came to exercise science (we were huge nerds, I know). I wasn’t doing any CrossFit-style training at the time but at one point, he asked if I had ever heard of CrossFit and showed me some CrossFit routines on his phone.

My first reaction was, “Whoa… that looks pretty intense. I don’t think I can do that. I’d be nervous about hurting myself.” He said, “Just give this routine a try…it’s for beginners.

I thought I was pretty fit and felt like he was challenging me, so I did it. Let’s just say the CrossFit routine he had me try, even though it was for beginners, was VERY intense; I was completely out of breath in under 5 minutes.

Fast forward a few weeks: I was starting to get into this style of training more and more. One day, I was doing a routine that involved box jumps. Box jumps are just like they sound – from a standing position, you jump with both feet onto a box that’s anywhere from 12 inches to 24 inches high. After you’ve landed on the box, with both feet, you jump back down. The box I happened to be using that day was 24 inches high. That day’s workout called for me to perform as many box jumps as possible within a certain period of time, so I was jumping up and down pretty quickly. My
colleague happened to see me and said, “You’ve got a lot of height to your jump. That box is too easy for you. Let’s make it a bit taller.” He grabbed those 45 pound plates (you know the ones that you normally put on the end of barbells) and laid 2 of them flat on top of the box. This added another 6 inches or so to the top. He said, “Now, go.”

Six inches doesn’t seem like a big difference, but when you’re performing a movement like this, it feels like he just added an additional 10 feet! He saw me clear the first two jumps and said, “Now, we’re talkin’” and walked off. I continued performing my jumps as fast as possible. I started to feel pretty wiped out, so I said to myself, “Ok, 2 more jumps and you’re done.”On the second-to-last jump, when I landed on top of the 45-pound plate, my left foot was planted, but my right foot didn’t quite land. I ended up wobbling a bit, trying to balance on my left foot. I quickly realized that this wasn’t working and will likely end badly for me so I hopped off. The problem was, because I didn’t have good balance when I leapt off the box, when I did land on the ground, I only landed with my left foot!

Surprisingly, I didn’t fall over completely – my right foot did eventually catch up. But as soon as my left foot hit the ground, a sharp pain shot up through my leg and into my lower back. The pain took my breath away. The leg pain quickly subsided, but the lower back pain didn’t. I hobbled away, wincing with every step. Luckily, it turned out to be just a strained muscle in my lower back – no major damage. But I was out of commission for 2 weeks – no gym, and definitely no CrossFit during that time.

Why the long, drawn-out story?

Much of the criticism when it comes to this style of high intensity training is the risk for injury. As I said before, many of the exercises involve working large muscle groups with sometimes complicated movements at a really fast pace. If your form isn’t perfect, the risk for injury definitely goes up.

Only a few studies have been done to see whether doing CrossFit is any more risky than say P90X or Insanity or any other structured routine. Most of the studies had some major flaws but the consensus is that CrossFit is about as risky as Olympic-style weight lifting, power-lifting, and gymnastics. But contact sports like American football or Rugby still beat out CrossFit when it comes to injury risk. Basically, CrossFit can increase your risk for injury, but it’s still safer than contact sports.

The other criticism is that with such high intensity training, you may actually break down your muscle tissue so much that it can actually start to damage your kidneys. I’ll briefly try and explain that process: when you experience muscle soreness, that’s because you have broken down some of that muscle tissue. When this happens, proteins from your broken down muscle tissue gets into your bloodstream. Your kidneys then filter those proteins out of your blood and you eventually excrete them through your urine. This is a normal process, but there have been cases where too much muscle breakdown caused the kidneys to become overloaded. This led to kidney failure in some people. But, this doesn’t appear to be a big concern for most that participate in CrossFit. If you are worried about this, just be sure to drink enough water during and after your workouts. Check out Episode 180 of Optimal Health Daily if you want more information about staying hydrated.

The last thing I’ll mention is that women often worry that if they start to participate in CrossFit, they’ll get “too big”– meaning their bodies will start to look masculine. That’s probably not going to happen. There are, of course, exceptions where you will see female CrossFit athletes that have muscles bigger than most guys’, but again this is the exception.

What’s the bottom line?

CrossFit will improve your overall fitness level. If you want to participate, be sure you are properly trained first. Take your time to perfect each and every move. This will help keep you safe and prevent injury. Have someone watch you while you perform the movements to make sure your form is perfect, especially before you think about adding more weight… or in my case, more height to your box jumps.

Listen to Dr. Neal address this topic on Episode 185 of the podcast Optimal Health Daily.