I met with professor Jimbo Saret, who has a masters degree in biomechanics and athletic training from Brigham Young University, and we were to road test a new performance athletic shoe. So I laced up and hopped on the treadmill.
"Hold it," Saret said. "You’re running wrong."
"Excuse me?" I replied, somewhat offended.
"You’re running on your toes. That’s bad for your feet."
So that explained all the foot and leg pains I had been feeling through the years. To compensate for my being flat-footed, I had conditioned myself to running on my toes, joining the 1% minority who do so.
Saret explained that the proper running stride is composed of three phases. First is the landing or heel strike. This is when your foot first makes impact with the ground. Up to three times your body weight strikes your feet, and the shock is mostly spread through the inner part of your foot. The foot compensates by pronating, or tending to roll inward. This is not a problem, unless you overpronate.
Next is the midstance, as your forefoot joins the heel on the running surface. The foot transforms from a loose structure to a rigid lever. This is also where the greatest chance of injury is, as your feet is rotating inward.
The third phase is the prolusive or toe-off phase, where the front part of your foot pushes you off towards the next stride. At this point, you need the energy from your footstrike transferred to your next step.
Typical sports shoes do not provide for the proper cushioning or guidance of our feet, generally, they just have a flat foam cushion which may be soft, but does not adjust to the needs of the foot in motion.
Adidas has attempted to solve this problem with a new technology called a-cubed (a3). Breaking down the foot’s motion, Adidas has combined different materials to cushion, guide and drive the foot on to its next movement, the a-cubed is meant to be an optimum energy management system.
First of all, the shoe has four cushions which look like colorful pillars, under the heel. The outermost cushion is a softer material that cushions at the point of greatest impact, and slows down the inward turning or pronation of the foot.
The second component in the new shoe is a pair of guidance elements on the outside of the arch and inside of the heel. Made of a firmer material and also convex shaped, the pieces center the foot in a neutral position as it makes the transition to the next step. Lastly, the other piece is convex to prevent the foot from tilting in the wrong direction.
All this is held together by a flat, slingshot-type of plastic called the transition plate. This moderates the transfer of energy from the heel to the front part of the foot.
I felt the effects of the new technology immediately. Trying out the a-cubed felt like strapping a guidance system onto my feet. Conscious of having a more pronounced heel strike, I could sense the guidance system keeping my foot in a straighter line. Secondly, the arch was more comfortable than other shoes I had tried. Third, I felt the atrophied muscles under my foot being used again. It took a lot of strain off the inner part of the foot, which was aggravated by my flat-footed condition.
In an independent biomechanics study conducted by the Technical University at Hamburg-Harburg, Germany, a3 showed a more neutral position for the foot upon touchdown compared to its chief competitor, significantly reduced pronation velocity, had a shorter contact time with the running surface, and was judged more stable.
Adidas is set to have the a-cubed put through its paces by a select group of sports media members. This is only one of three new lines the German sports footwear pioneer will be introducing this year. The other is its patented ClimaCool line, which allows the entire foot to breathe. The third is its Alphazeta group of shoes, which is made up of 26 different shoes, each filling a different need.
A majority of sports injuries are overuse injuries, resulting from the wrong turning and high impact on the feet whenever we walk or run. Just knowing what your feet need and which shoe will help you best will save you a lot of pain, not just today, but in the long run.