Womens Newton Running Lady Isaac S Running Shoe at Road Runner Sports
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Womens Newton Running Lady Isaac S Running Shoe

Women's Newton Running Lady Isaac S

Item #NWT111

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Reviews (14)
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Product Description:

Women's NEWTON RUNNING® SIR ISAAC S :: A running shoe so smart, Sir Isaac Newton himself would be impressed. The Women's Newton® Running Sir Isaac S is a stability guidance trainer designed to help you improve your midfoot/forefoot running style for more natural form. The Sir Isaac S delivers control of your late stage pronation to further improve your running biomechanics. With little effort on your part you'll find this hyper-intelligent running shoe intuitively guides your running form into the more efficient midfoot/forefoot running style.

Features & Benefits:

  • Beveled heel and toe: Helps guide runner easily into the midfoot/forefoot
  • Dual-density medial posting: Increase stability
  • Wider midfoot/forefoot and lugs: Adds stability and creates a softer feel
  • Midfoot Chassis/Shank: Adds support and stability
  • Carbon rubber outersole: Increases durability
  • Closed mesh on upper: Highly breathable, fast-drying, keeps small debris out
  • High rebound EVA: Stabilizes all foot types
  • WEIGHT: 8.9 ounces
Product NWT111 Review

Yes, I am wowed!


I was so skepital about theses shoes (esp. the price), but I am wowed! The fit, the stability, the cushion is wonderful, but I would love to have them in a different color. Even if you are a forefoot runner, you should follow the break-in guide offered by Newton. I've had these shoes for 2 months, and have used them for training for a 1/2 marathon. They are slippery on wet surfaces, and I would not recommend them for trails. I can already see the bottoms wearing down after only two months, so I don't know if I can shell out the [$] for another pair already. As other runners have mentioned, these shoes do seem to run small; I went up 1/2 size. Otherwise, a great shoe if you can afford them.

San Diego transplant

San Diego, CA


Best running shoe ever


I use to run local 5ks but my feet would hurt so bad that I had succumb to running a mile or two a week. After reading the reviews on the Newtons, I was somewhat hesitant but decided to give them a try. Wow, these shoes are the best, it is as if they designed them just for me. I am now able to run 5 miles (pain-free) each morning before work. The shoe is very light in weight and has great mid-sole support which is really important since it takes most of the pounding. Unlike my Nike's, the width is shaped to accommodate a bit of movement but please order one size up to ensure that you have the correct fiting. Trust me..these shoes are the best!

Lady Bug

Woodbridge, NJ


Love my shoes, but they wear down fast


I LOVE my Newtons. I really do. I've been transitioning to a fore-foot strike for awhile and tried several other runners but these were by far the most comfortable and the most supportive for that transition. The biggest complaint I have about these shoes is that they wear down far faster than any runner I've had before. I only got them a couple months ago and I already need to replace them. As much as I do not want to switch to another brand, the cost of replacing these every couple months is a bit much to swallow.


Baltimore, MD


Lady Isaac S


Shoes have a wide forefoot, narrow heel. I have large bunions and found these to be extremely comfortable out of the box. They work really well to control late-stage pronation and the lugs were perfectly placed where my foot lands naturally. Unfortunately, the lugs aggravated the balls of my feet by splaying out my toes. After having pain even after short runs, I became concerned that they might cause a stress-fracture and returned them. They also have very poor traction and I would not recommend them for wet-weather running.




For teaching an old dog a new trick


these shoes ran very small by my standards. I usually wear a 7.5-8 street shoe and order a 8.5 to run in, but I ended up with a 9 in the Newton's. the toe box is nicely shaped, but not very high, so, though I may have had the extra length suggested, I felt I was hitting the end of the shoe with every strike. Now that I have the correct size, they are quite comfortable to run in. I am new to a forefoot strike technique and these shoes have been helpful in getting me there.


Laramie, WY


great cushioning, good training shoe


Nice shoe, didn't need much breaking in, the shift to midfront strike is smooth. No complaints here, but I'm keeping an eye out, since other reviews say the shoe wears out easily and has poor traction. I'm using it with orthodics to control my pronation, which does the job, but it's hard to say if it offers enough stability on its own.




Best running shoe ever!


I will never wear another running shoe ever again!! I had so many problems with my feet, knees, and shins when I increased my miles. The second I switched to Newton's I lost the inserts (all 5 pairs that I had bought) and I ditched my old running shoes (about 3 others I tried) and lost any type of brace I had been using (IT Band, Knee support brace). I wish I could give every runner a free pair of Newton's so they could see how great they are!!




Love Newton


Love these shoes. Got them a few weeks ago, best running shoe I've ever experienced. Always had foot pain, knee pain or shin pain with many other brands... no problems in these shoes.


Janesville, WI


Worth every penny


I switched to running in Newtons exclusively almost two years ago with the hope of reducing the number of aches/pains that I regularly experienced post-running, particularly in my hips. Now, I know that they won't work for everyone but they sure did the trick for me! Of course, you have to be patient while breaking them in or you'll have some very sore calf muscles...but I have found Newtons to be well worth the wait. I own four different types of Newtons and these (Lady Isaac S) are definitely my favorite. Unlike other reviewers, I have not found them to be slippery on wet trails/pavement nor do they wear down any more quickly than other high-end running shoes. Please note that other Newton models do wear down more quickly (particularly those designated as "racing" models) but not the Lady Isaac S. It is surprisingly hearty.

Newton Nerd

Wheaton, IL


I love this shoe...


I've had this shoe for about a month now and I run 2x a week, about 3 miles each run. I'm a new runner and this is only my 3rd pair of running shoes. I started out with the Nike LunarGlide2 and I liked it, enough that went with the LunarGLide3. But I noticed that the cushion in the heal tended to compact rather quickly and I felt like my heal was in a hole. So I returned the 3's and tried this just to see what it was like. I was an instant convert. I ran about a mile on the treadmill and I didn't want to take them off. They are lightweight and the neutral running style they encourage is great. I'm trying to learn the Chi Running method and these fit nicely with it. I do have custom insoles as I moderately over-pronate. I wish they made this exact shoe in the water repelant fabric, but alas I'll just have to buy the Motion All Weather trainer.


Los Angeles, CA


I'm a believer!


I debated buying these shoes for a really long time because of the price. I finally decided to try them, as I was experiencing debilitating plantar fasciitis, that had been ruining my runs and recover for months. DAY ONE I noticed a difference and the morning after my run, NO pain in my feet as I got out of bed. I've run on them for 7 months now, have seen an increase in my overall pace and am ecstatic to say that I am pain free. Seriously love these shoes and without a doubt recommend them for anyone with plantar fasciitis issues.


Albuquerque, NM

I love this shoe!


I am currently training for a triathlon and marathon. The shoes have a more normal fit than other running shoes with pronation/stability support that I have bought in the past. They are so lightweight! The extra area of "padding" at the forefoot takes a little getting used to but is actually a great help. Plan for a little break-in time. If you are a mid-foot runner, the break-in time will be shorter.

Kim - Fitness Diva

Dumfries, VA


Love em, but sizing is tricky.


Bought them half size bigger as recommended, but I fell like my foot is floating around. I have to tie them super tight to prevent heel slippage.




Better on paper than the road, so far...


So far, I am not "wowed" too much for the price. However, they are comfortable on the foot, feel very light when running, and very breathable. The only problem I am having is with the arch support and my calves are super tight during and after the run...this may be a form issue though. Not sure yet. I am going to give them a bit more time before I decide they aren't what I was hoping for. The look of them is better than expected.

Carrie, the 1/2 marathon trainee

Seattle, WA


Womens Newton Running Lady Isaac S Running Shoe

4.4 14


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R-Gear QuickFit Insole

Price: $49.99

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  • Deep heel cup: Features the widest and deepest heel cup that offers maximum support and positions the soft tissue to help with natural shock absorption
  • Biomechanical shape
  • High-density foam: Closed-cell foam supports and cushions the foot for long lasting comfort
  • Odor-control coating: All natural coating that eliminates odor-causing bacteria
  • Stabilizer cap: The base of the insole that supports the rear foot and provides structure and stability to the foam layer


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