Finally Some Research on Crossfit!

High intensity, short duration exercise programs are growing in popularity. Evidence shows that such exercise programs lead to significant improvements in cardiorespiratory fitness (aka  aerobic fitness), body composition, muscular strength, and of course, health. Crossfit is a company that believes in this fitness principle and emphasizes programming focused on functional fitness. It has had much success and is continuing to grow in popularity. Unfortunately, there is no peer-reviewed research available on the effectiveness of Crossfit training. I am certain that anyone involved with Crossfit would happily provide anecdotal evidence that it has led to significant improvements in their fitness, health and quality of life. But for a program to be endorsed by professionals in the field, evidence is required.

As such, I was delighted to see a paper recently published in the Journal of Strength and Conditioning Research entitled “Crossfit-based high intensity power training improves maximal aerobic fitness and body composition” (doi: 10.1519/JSC.0b013e318289e59f); In Press).  I was particularly delighted to see that they used cardiorespiratory fitness as an outcome since the program consists primarily of strength and power based exercises. The study was a 10 week intervention with a total of 23 males and 20 females. The average age of this sample was approximately 32 years. Participants completed a maximal treadmill exercise test to determine VO2max; a measure of cardiorespiratory fitness that is considered to be the gold standard. The second main outcome assessed in the study was body composition as measured by the Bod Pod (air-displacement plethysmography). Unfortunately, this is not considered to be a highly reliable or valid method for assessing changes in body composition. The researchers would have been better off taking measures such as waist circumference, flexed bicep circumference or skinfolds at specific sites. These would have been more accurate in describing changes over the 10 week training period. Nonetheless, significant improvements in VO2max, body fat% and lean mass (i.e. muscle mass) were found. Another significant shortcoming of the present study is the lack of a control or comparison group. We know that exercise leads to improvements in fitness and body composition, but does Crossfit training provide additional benefit over other forms of exercise? We can’t answer that question with this data. More importantly, given the unreliable measure of body composition, the only take away from this study is that Crossfit training may lead to significant improvements in VO2max. Just in case I’m starting to sound cynical, I would like to emphasize that cardiorespiratory fitness or VO2max is the strongest predictor of health and mortality, so this is a very important finding.

TAKE HOME MESSAGE: There is no doubt that exercise is good for you and that high intensity exercise is better. For those of you interested in improving your health and cardiorespiratory fitness, Crossfit may be a great option. It provides a social support system, motivating coaches and a positive environment for exercise; all things that will really help you adhere to a Healthy, Active Lifestyle Forever!

NOTE: High intensity requires that you have a certain baseline level of fitness, so be sure to ease yourself into such a program; this will minimize your risk for injury and make for a much more enjoyable experience.


My Optimistic Journey with Barefoot Science Insoles

I have flat feet but I didn’t realize it until I started running 8 years ago. I was told to invest in custom orthotics and I trusted the experts, so I had a pair made. The orthotics helped at first, but 2 years in I ended up with a stress fracture. Perhaps other factors were to blame, but since I started wearing my orthotics I’ve had one injury after the other. This past year I was recommended by a physiotherapist to get a new pair since my old ones were clearly inadequate. So, a new plaster was made, another $500 paid, and I started running with new orthotics. Less than 5 months in a new debilitating injury appeared. It felt like I was going to be stuck in a vicious cycle of injuries, rehab, new orthotics and new running shoes. Lots of money spent, but no long-term solution on the horizon. If this story is starting to sound familiar, you might be interested to hear what I have to say.
I decided to go minimalist; not barefoot, just minimalist. I have an arch in my foot but it collapses when I’m standing or weight bearing. This means that strengthening/stretching the associated muscles and tendons could rectify the problem, at least partially. Yet, in all the years of going to rehab specialists, not one recommended exercises for my feet or ankles. Not one!
I did some research and found some appropriate exercises. I also got rid of my painful orthotics and started wearing running shoes with no arch support. I stopped running for a couple of weeks and through a friend of a friend I learned about Barefoot Science Insoles ( As a scientist I rarely buy something without seeing the evidence first but with no research trials available on the product and two extremely positive anecdotal reports, I decided to give them a try anyway.

WEEK 1: Last week, with a sample size of just one (n=1, literally) I began my research on the Barefoot Science Insoles. I put them in my running shoes and decided to pound the pavement. I mapped out a 5K, but it was a gorgeous day, so I ran just over 8K. It felt great. With the exception of a little IT band pain while running up the final hill and the smallest start of a blister, it went well. For the first time in months I was able to run more than 6K without ankle pain, knee pain or complete discomfort in my feet. Now obviously, it was day one, and I might have been a bit euphoric on hope.
Over the course of the week I have used the insoles in all of my shoes for workouts and work. My calves were easily fatigued and occasionally I experienced discomfort in my foot (primarily when on the elliptical), but all in all, things have been good. My ankle is feeling better; likely a combination of a decrease in running over the past couple of weeks and hopefully because of the new insoles.
Stay tuned for weekly updates on the insoles (it is a 7 week program). I will be sharing the good, the bad and the ugly. I also hope to hear from others that have used them or products similar to them.