Product Review–Newton Sir Isaac S
Right at the beginning of my half ironman journey, I went to a local shoe store to be fitted with a proper pair of running shoes. I was videotaped on a treadmill and placed on a machine that measured my feet and my weight distribution on my feet. An hour later I walked out with a pair of Saucony Guide 6 trainers with custom insoles.
I used those for about three months and when Sarah got a really substantial coupon for Newton Running shoes over the Christmas season. Full disclosure; our coach is married to the local Newton running rep and she is a Newton evangelist. Sarah got a pair of Bocas and the Newton Distance Elites and I ended up with a pair of Sir Isaac S trainers even though my Saucony shoes were barely broken in.
Newton makes a lot of bold claims in their literature and on their website about their shoes. Two of them stand out: 1) The lugs and low heel to toe drop encourage a mid-foot strike which is preferable to a heel strike and 2) The shoe is made of a material which has a “action/reaction” effect which saves energy.
The most noticeable difference between Newtons and competitive shoes from other specialty brands are the forefoot lugs that run longitudinally under the balls of the feet. To my knowledge, no other shoe brand does this. On the Sir Issac S shoes the lugs are a little less pronounced than they are on other Newton shoes, this is purposeful. This shoe is designed to transition a runner from normal running shoes to Newtons.
My experience with this shoe are generally positive. They stand out against the Saucony pair by having a very direct road feel. I am not sure if the lugs are exactly necessary, but I can certainly feel the “action/reaction” technology at work – a claim I was especially skeptical of at the outset. When I put on my Saucony shoes they feel dull and unresponsive in comparison. This surprised me in a good way.
I was also surprised by how much lower body pain I experienced using these shoes. To be fair, Newton warns of this but it was very noticeable. Even though I am an inexperienced adult runner, I did run cross country in High School so distance runs aren’t new to me. I am familiar with the leg pain associated with running. With Newtons that soreness moves from your quads and glutes to your calves, and in a big way. I started experiencing some Achilles tendonitis wearing these shoes and I am cautious about blaming the Newtons per se but I do somewhat blame the low heel/toe ratio. This engages the Achilles more and I think as a result of running in a way that I am not used too, my Achilles tendon needed to be stretched out and strengthened. As a test, I moved back to my Saucony’s for a few training runs and decided to stick with the Newtons.
One possible drawback which is worth mentioning are the price – which I can only describe as exorbitant. The Sir Isaac S trainers retail for $150 USD which is double what I paid for the Saucony Guide 6. Even if you made the argument that the Sir Isaac S and the Guide 6 are not in the same shoe class, the Saucony Kinvara 4 – which boast the same heel to toe drop ratio (4 mm) are only $100 USD. If the Sir Isaac S shoes last substantially longer than other trainers, this cost difference may be less extreme. I haven’t had them long enough to evaluate that aspect. However, it is worth mentioning that Newton is in a crowded field of companies in the specialty running business which include Brooks, Asics, New Balance, Saucony, Mizuno, and among the giants like Nike and Addidas. Newtons are more expensive than all of them.
For now, I like my Newtons and I will continue to wear them. When it comes time to replace them, I will have a serious look at other brands but I will probably stay in the Newton brand.