Tuesday, November 27, 2012

Minimalist Running Philosophy

"Are you into those toe shoe things?" I get this question all the time (they're asking about VFFs: Vibram Five Fingers) and I take a deep breath before responding because it's usually the beginning of a long conversation.

In reality, there's a spectrum in running philosophies that has two ends: 
  1. Traditional (post 80's): Running is high impact, damaging, and brutal but healthy exercise (or punishment). New technologies can prevent injury by providing cushion, forcing foot alignment (pronation), and helping your body adapt to the world around you.
  2. Minimalist: Running is the most natural form of human activity in the world. We've been doing it for thousands of years, anyone can do it, and it's best done (nearly) naked. Any interference between the human body and the ground is screwing up a naturally harmonious relationship that can lead to lifelong running health. 
While I don't train in VFFs, the last 8 years have landed me closer to the 2nd end of the spectrum. I grew up running in standard high cushion trainers like everyone else from middle school to early college, and majority of my most competitive friends (including those qualifying for the Olympic trials) still tend to train in more traditional trainers. However 8 years ago (mid college racing & suffering shin splints) I started reading more about minimalist philosophies and have been running in some form of racing flat or minimalist shoe ever since. I consider myself a little too 'serious' of a runner to train/race in VFFs (be honest - you don't see these things in the Olympics) but I do own some, and I do think aspects of them have merits and may work great for some runners. When figuring out where you lie on the spectrum (or where a shoe lies) there are 5 major components that separate the two ends:
  1. Heel/toe height difference
  2. Padding/cushioning
  3. Support
  4. Foot & toe freedom/flexibility
  5. Weight
Note: Scientific studies do exist that back up the minimalist side of all these arguments, I just don't have them handy at the moment. I intend to make this post a work in progress and add citations but if you have any articles/papers you think are interesting include them in the comments, I'd love to see them.

1. Heel/toe height difference
This is one of the most impactful (and difficult to adjust to) differences between traditional and minimalist trainers.

  • The traditional view is that running/jogging is a heel to toe exercise: land on heel, roll forward to forefoot, lift, repeat. All that pounding on the heel sends a lot of shock up the leg, so running shoes have been designed with a large, cushy, heel to absorb  that initial impact. 
  • The core minimalist idea is that the human body as a machine is meant to absorb impact naturally by landing on the forefoot and absorbing force through the foot arch, & natural leg springs (achilles tendon & calf muscle) as the heel approaches the ground. If you're coming from high heeled shoes it takes significant time & work to adjust to this difference, and I would strongly consider doing it gradually.
Heel > Toe differences can range anywhere from 0mm in a Minimus to 12mm in a trainer. Check out the New Balance MR00 below (12mm heel, 12mm forefoot) vs the Nike Air Pegasus +29 (32mm heel, 20mm forefoot).

2. Padding/cushioning
"Why is the ground so hard?" is a typical first comment when trying on minimalist shoes, and it will probably be the first thing your feet notice.

  • The traditional view is that running is a high impact exercise, and reducing that impact at the ground will prevent harm to the body.
  • The minimalist view is that if you let the body act naturally, the force is dissipated through the body's intended absorption points. One aspect of this reduction is by using a forefoot strike instead of a heel strike (discussed above).

    The other aspect is that our bodies are actually very smart. The human foot is meant to be our connection with the ground - it's great at sensing it's environment & keeping us balanced. That means when you stride onto a cushy, unstable, surface the foot will naturally push down to find a balance point. And when you stride onto a hard, unforgiving, surface the foot will naturally land delicately, step lightly, and minimize contact. If you don't believe me try jogging barefoot across your driveway or sidewalk, then do the same thing with your shoes on (seriously). The effect is that by reducing padding you naturally step lightly, and not only does this reduce contact at the ground level, but the natural change in form makes a dramatic difference at how the impact is propagated up the body. A natural strike shows less force transmitted up through the knees and hips.

    Barefoot runners take this to the extreme and run entire marathons barefoot; personally I like a fairly thin layer of protection to the ground and I find thin racing flats or minimal trail shoes to be a good balance. Again, take a look at the picture above of the Minimus vs the Pegasus and consider even the thinnest part of the Pegasus is the 20mm cushioned forefoot vs the 12mm rubbery Minimus sole. 
3. Support
This is something minimalist converts need to be very cautious about.

  • The traditional view is that the foot is weak & needs arch support.
  • The minimalist view is that fundamentally, an arch is one of nature's strongest mechanisms. It's only weakness is if you stick something under it (which is exactly what arch support does!). The idea here is that in the western world our arches have become extremely weak and under utilized (see the number of flat footed people in the US) but that this can be reversed. There's near 0 prevalence of this disorder in undeveloped countries that haven't grown up with shoes.

    So the key here is that support is extraneous once your foot is used to supporting itself. You just have to be careful during that building process. 
4. Foot & toe freedom/flexibility
While the first two aspects probably make a bigger difference in your running mechanics  the visible toe freedom is what has made VFFs so well known to runners & onlookers.

  • The traditional view is that shoes just need to contain your feet. As long as they're not giving you blisters or uncomfortable they're probably fine.
  • The minimalist view is that toes should naturally spread & grip when barefoot, and normal shoes inhibit this.

    My personal view is that I like a wider forefoot with some space for movement (plus I run barefoot in my shoes which I think gives me a much better feel for the ground) but I've never felt like VFFs were really doing great things for my toes. 

5. Weight
I almost didn't include this as an aspect, because it's really a function of the above 4 design choices. However I mention it in all my reviews and I do consider it when buying shoes so I thought it should stand on it's own. Since barefoot is obviously the lightest shoe possible, minimalist runners love light shoes. I love the feel of light shoes but I also enjoy the mental aspect of knowing I'm not weighing my feet down with anything extra. Overall weight tends to be driven down by less cushioning, lower heels, and less support so if you pay attention to the first categories you'll naturally end up with a lighter shoe. It is fun to pay attention to though and the weight of my shoes always shocks my friends.

Monday, November 26, 2012

New Balance MR00 Minimus Road Review

New Balance has fully embraced the 'minimalist' movement and their latest road shoe shows just how serious they've gotten. I actually picked up this pair at a local store over Thanksgiving (Playmakers, can't be beat) and thought they were just racing flats. The flat style & light weight were enough to try them on, and the feel on foot was amazing. So imagine my surprise when I went to look up their actual stats after a couple runs and I realized they were from the Minimus line, and not regular flats. It was a pleasant surprise, and for the amount of comfort they provide I was shocked to see they actually have a 0 heel/toe drop.

Stats: Weight & Toe Drop
At 6.1 oz it's definitely in the featherweight class (I'm not sure if anything will be lighter than the old 3.9 Mizunos) but I think the extra heft comes from the quality Vibram sole (more on that later). On top of the light weight, they actually measure 12mm in the forefoot AND 12mm in the heel for a completely flat shoe. I was surprised, because the 0 drop shoes I've ran in before like the Merrel Trail Glove always felt like my heel was low, which made sense since most racing flats I've trained in still had a 3-5mm raised heel. However these MR00's felt more like the Piranha's or Wave Universe, so it was a pleasant surprise since that means I should be getting more natural strike out of my mid/forefoot & heel impact dampening from the little extra stretch in my calf & achilles.

Sole (Vibram)
The biggest problem with the lightweight flats I like to train in is often the sole. Racing flats love to save weight by using a hard tack that feels plasticky on the bottom. The New Balance MR00's go in the complete opposite direction with a great rubberized Vibram sole. The result is a great feel on the road, and I'm guessing great durability. I'll update this review after a few hundred miles and check in on that.

Fit / Feel
Technical stats aside, this is the reason I bought these in the store. New Balance gave these a nice wide forefoot that feels secure on foot but roomy, and a great inner lining that feels soft barefoot. The low, but solid sole is much better than the thick rubber of Nike Frees, and also helps prevent pronation since the sole can't compact all that much compared to a cushier shoe. These feel just as good as the Mizuno Wave Universe on foot, but the rubberized sole means they feel even better one when you start making contact with the ground.