Sunday, December 14, 2008

The real perfect push-up

I was talking with a friend of mine earlier this week who had used the Perfect Push-up. He liked it. He also made a great comment that really summarizes the use of exercise gadgets- "Hey Chimes, you know what the real perfect push-up is? Actually doing them."

I think that is perfect. Just like the old Nike commercial says- "Just do it!"

Monday, December 8, 2008

Cushioned running shoes for feet with high arches

The choice of which running shoe a runner should use is largely determined by their foot arch and the type of motion the foot makes through the stance phase (the portion of the running cycle when the foot is in contact with the ground).

There are two common subsets of foot and motion patterns seen in runners. The most common pattern is the overpronator, which is often associated with a flat arch. The second and less common category is the high-arched underpronator, which happens to be the category I belong to.

To understand how these foot mechanics influence choice of footwear, it is important to understand foot pronation. Foot pronation is a natural roll of the foot that occurs during stance phase that serves to help absorb some of the force of impact. When the foot first contact the ground, most people start to roll almost immediately to the outside of their foot (this is why, if you look at the shoes of most people, you see greater wear on the outside of their heel than the inside of the heel). What happens in the middle of stance phase is that weight stays along the outside of the foot arch as the runners body weight is transferred over the middle of the foot.

The main distinction between over- and under- pronators occurs during the end of stance phase. Underpronators start rolling toward the big toe, and keep on going. This pronation is useful, as it helps absorb the force of landing, which is several times bodyweight. The problem with overpronating is that as the foot keeps rolling without control, it drags the rest of the body with it, which causes excessive strain up the kinetic chain (e.g., the excessive pronation can pull the leg bone, the tibia, with it the foot, which can cause strain at the knee). Therefore, runners with excessive pronation are often advised to wear motion control shoes.

The underpronator, like me, has the opposite problem. In their feet, the foot does NOT roll sufficiently toward the big toe. Remember- pronation is an important shock absorbing motion. Therefore, in runners with high arches and underpronation, the general recommendation is to avoid motion control shoes and use running shoes that have extra cushioning (to compensate for the lack of absorbtion from the natural pronation motion).

A recent study from the American Journal of Sports Medicine confirmed the shoe recommendations for high-arched runners.

Caleb Wegener, Joshua Burns, and Stefania Penkala Effect of Neutral-Cushioned Running Shoes on Plantar Pressure Loading and Comfort in Athletes With Cavus Feet: A Crossover Randomized Controlled Trial , Am J Sports Med 2008 36: 2139-2146

In short, this study confirms the recommendations above for the high-arched runner.

For the record, the cushioned shoes that were examined were the Asics Nimbus 6 and Brooks Glycerin 3, and the control shoe that was examined was the Dunlop Volley. This was a well designed study that used a cross-over study design, meaning that each participant started with either a cushioned shoe or the control, and then switched groups. The examiners also assessed both pressure distribution and comfort level of the runners.

Based on this study, the recommendations listed above still apply. Based on my personal anecdotal experience, it is important for runners with high arches and underpronation to look for a shoe that is BOTH heavily cushioned AND not motion control. My experience has been that it is hard to find running shoes that do not have some component of motion control built into the shoe. Since overpronation is the more common foot problem, most shoe manufacturers tend to build some motion control into almost all of their shoes, even their heavily cushioned models.

As a practical matter, this can be a challenge. If you go to many running shoe stores, the clerks sometimes will not know the properties of the individual shoes. My recommendation is to first scout out the shoes you are looking for on a good running shoe site (I tend to use, and then look for shoes that fit your category. Once you find a shoe you like, stick with it. Stores that specialize in running shoes (e.g., in Chicago and Pittsburgh, Fleet Feet is a good store) tend to have experienced sales people with good knowledge of what type of shoe is right for you.

Sunday, December 7, 2008

Iron Gym Pull Up Bar

I am doing another product review. One of my readers (that is, one of my grand total of 5 readers) pointed out "for a guy who claims not to be commercial, you sure have a lot of product placements. And while I'm at it, exactly how many mentors do you have?"

Addressing the second question- I have a lot of mentors. I've been very fortunate that many people have cared enough to invest their time in my success. The only payback I can give them is that I try to take their advice to heart and pay it forward to the next group of trainees.

As for the product reviews, let me clarify- I do not take any money or compensation from any sponsor. That may change in the future- I can only hope that I am successful enough that people will pay me for my time. What I can promise is that I will fully disclose any financial relationships I have with any products.

Now, then ...

I am reviewing the Iron Gym Pull Up Bar. Right now, they are selling them for $29.99 at Bed Bath & Beyond.

I will first make a quick plug for Bed Bath & Beyond. You have to love their ubiquitous coupons that never expire, so you never pay list price for anything. Even better, though, is their return policy. I go through blenders fairly quickly- I use mine every day for protein shakes, and occasionally burn out the motor. I used to buy them from other vendors, but because the return policy is so good at BBB, I don't think I will ever buy a home appliance anywhere else. Great customer service goes a long way in building loyalty.

Back to the Iron Gym- it's basically a pull-up bar that can be attached without hardware. It claims to be used for other purposes, but I suspect that 90% of the people who are buying it just for pull-ups.

It does exactly what it says it does- I really like it. I am a big man (well over 200 pounds), so I am skeptical that any bar can really support my weight. But the Iron Gym feels pretty sturdy, and is easily attached to a door in under a minute. I don't see any issues at all with structural integrity of the door, and it has not marred the doorway at all.

Additionally, it allow for multiple grips- I use 2 chin positions, 1 neutral grip (which most bars don't allow for), and 2 pull up positions. I am 6'3", so a concern with some bar designs is that there is not enough clearance, but the bar only extends 5" below my door, so I can easily do pull ups with my knees bent.

So, I am probably the perfect demographic for someone who will benefit from this bar in that:
1. I am able to do a pull up
2. I don't want to permanently install a pull up bar
3. My gym doesn't have a pull up bar, which is a shame, since it's one of the most important resistance exercises one can do

It is perfect for me. On the days when I do upper body weights at the gym, I'll do pull ups on the Iron Gym at home. I usually work for several hours at my computer every day, so I periodically get up anyway for some other reason. When I get up, I make a point of doing as many pull ups as a I can on the bar. Since I, like most people, can't do to many at one time, this is a way to make sure I get in a fair number of repetitions over the course of the day.

There are some people who should avoid this product:
1. If you cannot do a pull up- you should be able to do at least 1 in at least 1 grip position to really benefit from the bar.
2. If you are over 30o pounds- at some point you may damage the door frame. I don't feel like I am approaching that limit, but the product label recommends 300 pounds as a weight limit.

Overall, I think it's a terrific product that fills a real need, and is reasonably priced.

Saturday, December 6, 2008

Medical perspective on Mixed Martial Arts (MMA)

I am a big fan of mixed martial arts, also known as MMA, most commonly associated with the world's largest MMA organization, the UFC (Ultimate Fighting Championship).

Max Kellerman, the great sports commentator and noted boxing fan, frequently notes that fighting is the most intrinsically interesting of all sports. A thought experiment he likes to make is to imagine that you are in the middle of an intersection of two streets with a crowd of people. Imagine that on three of the street corners there is a different sporting event going on- one street corner has a baseball game, another a basketball game, and on the third a football game. The crowd at the intersection would likely have their attention split amongst the basketball, football, and baseball games- none would dominate interest.

Now imagine that on the 4th street corner a fight breaks out. Nearly everybody would stop watching whatever they were watching and turn to watch the fight. It's simply more interesting- fighting is, at it's essence, the most purely interesting of all sports.

Max Kellerman made this argument in defense of boxing, but I think it applies even more to MMA. In recent years, MMA has become the dominant combat sport in America. The stars of the UFC- Brock Lesnar, GSP, Fedor, Forrest Griffen- are now bigger stars than the boxers. UFC fights dominate on pay per view, and the UFC fight cards draw bigger crowds in Las Vegas than do boxing cards.

Senator John McCain famously referred to the early sanctioned MMA fights as "human cockfighting." I have tremendous respect for Senator McCain, and there is some truth in his assessment of early MMA- the rules were not clearly established, and the early cards often seemed to promote the brutality of the exhibitions rather than the elgance and athleticism. It was being marketed as show rather than a sport.

I also think that, at least in part, McCain was speaking as a boxing fan. He loves boxing, and was bothered by a newer sport supplanting boxing. I love boxing too- like most people of my generation, some of my favorite sporting moments as a fan are the great Sugar Ray Leanord/Marvin Hagler/Thomas Hearns/Roberto Duran middleweight bouts, or the Evander Holyfield/Mike Tyson era.

But, I am a much bigger fan of MMA now than boxing, for 3 major reasons:
1. As a sports fan, I think the matches are far more entertaining.
2. As a biomechanists, I think MMA is more elegant. Watching a great multidisciplinary fighter, like Georges St Pierre, is like watching a text book on human movement. It is similar on some level to watching a great dance troupe like Alvin Ailey or great gymnasts like Cirque de Soleil, only with a greater sense of urgency because it is taking place in the context of a fight.
3. As a physician, I think MMA is safer than boxing.

The last point is the major one that inspired me to write this posting.

I don't think it has always been true that MMA is safer than boxing. The early sanctions to clean up the sport, though, have been very successful. There are a few things that make the sport safer now:

1. Most importantly, encouraging a referee to step in quickly when an opponent cannot defend themselves.
2. Rules changes to minimize things like small joint manipulation and kicking an opponent in the head when they are on the ground, that remove some of the most dangerous elements.
3. Creating weight classes, which minimizes the risks of greatly mismatched opponents
4. Moving away from tournaments, which increase the risk of cumultive trauma
5. Increasing popularity, which places an impetus on keeping stars healthy, and creating enough stars that they can alternate on who the headliner is for the card. A top fighter may only have 4 fights in a year

There have been several studies in the past few years that have tried to assess the risk of MMA, both overall, and in comparison to boxing. I don't think the data is conclusive, but my impression is that MMA is safer.

The big difference, in my opinion, is concussion rate. Concussion, or mild TBI (traumatic brain injury), is in my opinion the most serious risk of combat sports. I think the risk of concussion is significantly higher in boxing for several reasons:

1. In MMA, there are many other ways to win, including submissions. In boxing, the main goal of the sport is to give your opponent a concussion and knock them unconscious.
2. The gloves: The thick padded gloves in boxing probably increase the rate of concussion by several mechanisms. I think the most important one is that they protect the hands, so there really isn't much disincentive from punching your opponent in the head. In MMA, the thinner padding of the gloves results in punches hurting the fighter's hands more. This often results in fighters trying alternative approaches, including takedowns and submissions, rather than just punching. Of course, in boxing those options don't even exist. Furthermore, the padding of boxing gloves widely distributes the force, which may minimize the knockout potential of any one punch. This can lead to greater cumultive trauma over the course of a fight.
3. Quick stops. Right now, refs in UFC and most of the other sanctioning organizations are quick to stop fights when fighters cannot defend themselves. Sometimes this is frustrating to viewers, but I think it is one of the most important safety factors for the sport, and it is the one variable that could dramatically change the sport. If UFC wants to continue as a mainstream sport, they MUST continue to protect their fighters.

Enough with medical talk ....

I am very excited about the sport of MMA right now. There are some huge, huge fights on the horizon. UFC has done a tremendous job of promoting their fighters, and I don't know an MMA fan who isn't simply giddy in anticipation of the December 27 card coming up, with 3 fights fully worthy of main event status.

The one major logistical issue that I see right now is that 2 of those most appealing fighters on the planet, Fedor Emelianko and Gina Carano, are not under UFC contracts. I hope that changes. Fedor is, in my opinion, the best fighter who has ever lived, and I want to see him fight all of the best competition available. Gina Carano is a phenomenon in her own right- a legitimately terrific fighter whose marketability is off the charts. A series of fights between her and Cris Cyborg and Tara Larosa would easily be the most heavily anticipated fights in female fighting history. I hope they happen.

Friday, December 5, 2008

Where's the sun?

Now that I've lived in Pittsburgh for a few months, one of the most striking things to me is the absence of sun.

I had heard that Pittsburgh was similar to Seattle in terms of cloud cover. During the summer, it wasn't an issue, and indeed summer in Pittsburgh was beautiful. But once the time change happened, it was striking how little sunlight I saw every day. It is not uncommon for me to see no sunlight the whole day.

I think this has several health implications for the people living in western Pennsylvania. First, people like sun, and the absence of sun makes it less likely for people to be active outside. I am curious which is a bigger deterrent for outdoor activity- weather, or sunlight. Anecdotally from speaking to work colleagues, I think it's sunlight. And this can lead to less exercise.

The second issue is Seasonal Affective Disorder (SAD). I am starting to believe this is much more common than has been commonly realized. In particular, I see many patients with musculoskeletal pain, and I believe there is a high comorbidity with SAD in my patients.

I suspect that one of the changes we will see in the coming decades in the management of musculoskeletal conditions is the realization of the extent to which external environmental factors, including sunlight, contributes to our sense of well being.