Newton Sir Isaac Review- Synopsis
Quality but fairly expensive cushioned trainer designed for a midfoot strike. This particular model is designed for runners that prefer cushioned trainers and is not intended to be a “barefoot” replacement. The shoe would be a poor choice for barefoot or minimalist shoe runners due to a lack of ground feel, inadequate room to allow toes to splay, weight, and inflexible design. The Sir Isaac would be a very good choice for runners that do not want to give up cushioned trainers but are interested in changing to a midfoot strike.
Newton Sir Isaac Review- In Depth
When I decided to get into the reviewing game, I knew this time would come. I would have to review a shoe I did not like. It was inevitable, really. As a barefoot runner, every shoe will be inadequate in some way. Still, I knew I had something to offer my fellow barefoot runners. When conditions are either too cold or too hot, or the terrain is too rough, shoes are a necessary evil. I could help my barefoot brethren make an informed decision.
The moment I opened the Newton box, I knew this would be that shoe. There sat a giant, heavy, imposing piece of rubber that looked as if it could eat every other shoe in my collection. This shoe was the exact opposite of my ideal shoe. How could I possibly review this shoe? How could I even run in this shoe?
It was clear this shoe was a cushioned trainer. I haven’t run in a cushioned trainer in six years! This could be very interesting.
The specific model, the Sir Isaac, was unfamiliar to me. A quick check of Newton’s website revealed this shoe to be their transition shoe. It was intended to help runners transition from traditional cushioned trainers to Newton’s cushioned trainers. Great. Not only is this a heavy, cushioned shoe… it’s the heaviest in Newton’s lineup!
IMPORTANT- Newton DOES make several models that would be much more desirable to a barefoot or minimalist shoe runner, such as the Racer. I should be reviewing this shoe in the near future. The first part of this review is done from the perspective of a barefoot runner. Later in the review, I address this shoe as a replacement for cushioned trainers.
Still, I was determined to give the shoe a fair chance. I knew many runners that have tried Newtons. About 75% loved them. For any shoe, that is a very good percentage. Unfortunately, none of those runners were barefoot runners.
A quick review of their website refreshed Newton’s theories. The shoes are designed to allow runners to use a forefoot or midfoot landing. Most cushioned trainers… okay, ALL cushioned trainers are designed for a heel strike. It is possible to use a midfoot strike in other cushioned trainers… it’s just difficult.
This particular model can be found online for around $150. While the price is steep, this is a very high quality shoe. Construction appears to be excellent. Based on my discussions of long-time Newton fans, these shoes are above average in regards to durability.
One quick note about Newton’s marketing… they associate themselves with barefoot running. Many shoe companies, even some that produce excellent minimalist shoes, use the same marketing strategy. This really annoys me. No shoe will approximate the same experience as running barefoot.
Newtons promote a midfoot strike by mostly eliminating the heel drop (difference between thickness of the sole compared to the thickness of the forefoot) and adding technology that will return the energy from your foot hitting the ground. As the theory goes, this will allow the shoe to propel you forward with each step.
At this point, I have to add this disclaimer. I’m a barefoot runner. I base all my reviews off the premise that bare feet cannot be improved upon by any technology. My own opinions of this shoe are not the opinions of all runners that have used this shoe. I think barefoot runners could generalize my review to their own probable experiences with this shoe. However, if you currently run in cushioned trainers, most of this review will be irrelevant.
Let’s jump into the actual review. The first time I wore the shoes, I immediately felt like I was wearing stilts. I was definitely not used to having so much material between my feet and the ground. The Sir Isaacs’ sole is approximately 30mm. The thickest shoes I normally wear have a 4mm sole. That 24mm (close to one inch) felt VERY significant.
As expected, the shoes felt like walking on giant circus peanuts. It took some time to adapt to the squishiness (very scientific term) of the shoes. Aside from the thickness of the sole, I also noticed the toe box was tight relative to the minimalist shoes I normally wear. My other preferred shoes have a wide toe box which allows the toes to splay.
The weight of the shoe was also significant. The weight is listed at 10.9 ounces. It’s not significantly more than my Terra Plana Vivo Barefoot EVOs or Vibram KSOs, but it felt significantly heavier. I believe the overall girth of the shoe created this perceptual illusion.
The last thing I noticed- the “Action/Reaction Technology” that propelled me forward really did seem to work as described. It was a very foreign and unwelcome feeling as it added to the cushioned feel of the shoe. I had to wait about a week to actually take them for a run as I was testing the EVO at the same time.
The First Run
I was dreading this run. I tried to force my negative expectations out of my head. This would be a three mile run on relatively flat roads composed of asphalt and gravel. The run started off a bit slow as it took some time to acclimate to the weight and lack of ground feel. After about a mile, I settled into my normal gait. Over the two miles, these were my initial impressions:
• The shoe actually allowed me to use a version of my normal midfoot gait. I was a bit surprised by this even though it is Newton’s main selling point. +1 for Sir Isaac.
• The “Action/Reaction Technology” was more distracting than helpful. It could be best described as a bouncy feeling. I hate cushioning under my feet. Not only did this feel like running on pillows, the pillows pushed back after each foot strike. -1 for Sir Isaac.
• The toe box was uncomfortably narrow. This would prove to be a major red mark for me. -1 for Sir Isaac.
• The shoe didn’t feel as heavy as it had when I wore it at home. I definitely knew I was wearing a shoe, but it wasn’t as bad as expected. +1 for Sir Isaac.
• The complete and total lack of ground feel made the run… well… feel like work. Being able to feel the terrain is one of the great joys I get from running. -1 for Sir Isaac.
• After two miles, my feet were already hot. Ventilation in these shoes was well below my expectations. -1 for Sir Isaac.
My second run was roughly the same distance over the same type of terrain, and the experience was identical to the first run.
The third run was a longer run of about 12.5 miles. I had the same complains as before, but the run went well. I was able to complete the distance without developing any unusual pains. This is significant. With any other non-minimalist shoe I’ve tried, injuries spring up on longer runs. I’ve tried racing flats to no avail. It was too difficult to maintain my normal gait. The Newtons did not interfere with my form. Based on this alone, I believe Newtons really are effective at allowing a midfoot strike.
My final test run consisted of about three miles on lightly technical trails. The Sir Isaacs still felt heavy and overly-cushioned, but I was able to identify one more positive characteristic: these shoes have awesome traction! Also, the shoes do not encourage heel striking, but they do allow it. When running down hills, it can be difficult to maintain a midfoot strike without eventually developing patellar tendon pain. My usual remedy is to traverse down hills using a slalom skiing technique. The Sir Isaacs pretty much allowed me to bomb down the hills at full speed.
I may be the worst possible reviewer for these shoes. Barefoot runners are not a demographic that will appreciate these shoes. I would not recommend these shoes to current barefoot runners. Likewise, I would not recommend these shoes to runners transitioning to barefoot running. Runners that enjoy minimalist shoes will find the Sir Isaacs to be too much shoe. There are other shoes in the Newton lineup that would be more appropriate.
Based on conversations with other normally-shod runners, Newtons do meet the needs of shod runners adapting a midfoot strike AND have no intention to run barefoot or in minimalist shoes. The cushioning aspect that I found very annoying is preferred by many runners. The weight is actually lighter than most cushioned trainers. I talked to several runners that were very happy with these shoes. Newton has developed a reputation of producing quality shoes that meet the needs of many runners… I’m just not one of those runners.
Some of my running partners have no interest in barefoot or minimalist shoe running. I will suggest Newtons as a possible replacement for their Nikes, Asics, and Brooks cushioned trainers. There is merit to adapting a midfoot strike, and Newtons accomplish this. They will meet the needs of anyone that is unwilling to give up the cushioning of their traditional trainers, but want to adopt a midfoot strike. For this demographic, the cost of Sir Isaacs would be well-justified.
This is a good shoe, just not for me. It simply does not fit my style of running. Had I found this shoe prior to running barefoot, I may not have tried barefoot running.
None of my favorite running stores carry Newtons, so I recommend you purchase them from Marathon Sports in Boston. They’re barefoot-friendly!
This product was provided by the manufacturer.