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Saucony Fastwitch 9 Review

The lightest stability racing flat on the market returns lighter than ever.  The Saucony Fastwitch 9 has been a favorite of mine for years.  The light stability combined with a light ride that started only a few versions ago makes for a fast and versatile shoe.  Now in the 9th version, the weight has dropped further but still remains a snappy, supportive and responsive ride that is my personal first choice for speed workouts and shorter races.  Although many will be able to use this for a variety of distances, let's dive into the latest release of the Fastwitch.

Specifications (per Running Warehouse)
Weight: 6.0 oz
Stack Height: 19 mm / 15 mm
Drop: 4mm
Classification: Stability Racing Flat


The sizing of the Fastwitch series has been small up until the last two versions.  The Saucony Fastwitch 9 fits true to size with a snug racing fit.  I typically wear a size 10 in most shoes and version 9 fits perfectly.  The heel is extremely snug and holds the foot well with an almost non-existent heel counter.  The midfoot opens up more then tapers into a slightly spacious forefoot.  The forefoot is not overly wide, but the engineered mesh does slightly stretch to accommodate different forefoot.  Overall the Fastwitch 9 still has a snug fit but is not overly narrow.  The midfoot mesh responds very well to the laces and can be changed depending on how much room you need.  Runners with a variety of foot shapes will appreciate this shoe, but those with overly wide feet may have some trouble.


The sole of the Saucony Fastwitch 9 has been completely redesigned.  Although a midfoot post is still present, the remainder of the sole has been replaced with a triangular design.  The design creates a far smoother ride and much better flexibility in the forefoot.  This allows for a very smooth toe off but also creates extremely good traction on a variety of surfaces (even on wet road).  The cushioning still remains on the firmer side but the SSL EVA provides good protection and responsiveness at a variety of speeds.  The sole sits the closest to the ground of any other light stability racing flat, which contributes to this shoe feeling like a 5k-10k racing flat.

The Fastwitch 9 is listed as having a 4mm drop but feels more in the 4-6mm range.  This is low enough to be fast, but seems to be forgiving enough that my calves can still handle longer workouts.


As with previous versions, a duel density medial post is present in the midfoot of the Saucony Fastwitch 9.  However, unlike previous versions, the stability feels more present.  The medial post sits against the foot in what feels like a raised medial edge of the sole.  This sensation quickly disappears and the foot settles in.  I was impressed that the stability from the Fastwitch 9, while mild, was able to carry me through very long speed workouts with little fatigue.

The midfoot, while somewhat narrow, remains stable thanks to the post.  The forefoot opens up with a wider last.  Although there is no post in the forefoot, the wider footprint and typical Saucony outsole flare makes for a stable and smooth toe-off.


The Saucony Fastwitch 9 is a fast shoe.  Due to the lightweight, close to the ground nature, this is a perfect choice for fast days, speed workouts and 5k-10k races for those looking for extra stability.  Those who are more durable could easily use this for a half marathon and others will be able to take it up to the full marathon if they are used to running in such light shoes.  For most individuals this is a 5k-10k racer.  The SSL EVA sole is on the firmer side.  It makes it very easy to get up on your toes to run fast, but still provides enough protection to handle some higher distances.


PWRTRAC outsole has remained almost unchanged in the fast road and track miles I have put on this shoe.  There is no wear after 24 hard miles on the outsole and the cushioning has remained consistent.  The firmer and responsive ride has remained similar.  The great flexibility in the forefoot is a key factor that allowed me to do a long workout right out of the box.  The Saucony Fastwitch 9 required no break in for me, but I always suggest you get used to any shoe before racing in them.


Although there is a duel density medial post in the midfoot to provide mild support, there are other elements to this shoe that add stability.  Saucony frequently uses outsole flare in their shoes, particularly in the forefoot.  Flare describes the extension of the sole beyond where the foot sits.  This increases surface area, thereby improving stability by providing resistance to certain directions thanks to the wider base.  For more information, read my post on Sole Flare HERE.  There is some medial and lateral forefoot flare in the Saucony Fastwitch 9, which creates a very stable toe off at the forefoot.  The deep flex grooves in the forefoot also help guide the foot forward by facilitating motion forward (and not side to side).  As always, there are many ways to create stability in a shoe and I applaud Saucony for using multiple methods in this fantastic lightweight stability shoe.


The Saucony Fastwitch 9 is for those who need a little stability when racing fast.  It is an exellent 5k-10k racer with the range to go longer if you can.  As mentioned in my post on the New Balance 1500v5, although stability racers are becoming more rare, I hope Saucony continues to make this shoe as it is not only the lightest stability racer, but the fastest in my opinion.  The snug adaptable mesh provides a great breathable hold on the foot.  The midsole is responsive and extremely light.  Finally the dual density medial post provides light stability along with other elements that will keep you on the right track even when you fatigue.  A great redesign that is well worth a look for newcomers as well as those with extensive experience with the Fastwitch series.


New Balance 1500v5 - Heavier, more midsole, better for 10k-half marathon races

Brooks Asteria - Heavier, more cushioned, better for marathon racing or as a lightweight trainer


Fit/Upper          9/10
Ride/Midsole    9/10
Stability            9/10
Speed                9/10
Durability          9/10

Total Score: 90%

Thanks for reading!

Editor's Note: As always, the views presented on this website belong to myself or the selected few who contribute to these posts. This website should not and does not serve as a replacement for seeking medical care. If you are currently injured or concerned about an injury, please see your local running physical therapist. If you are in the Los Angeles area, I am currently taking clients for running evaluations.

Dr. Matthew Klein PT DPT OCS 
Doctor of Physical Therapy
Board Certified Orthopedic Clinical Specialist
Kaiser SoCal Manual Therapy and Sport Fellow Graduate

***Disclaimer: These shoes were purchased for their full US retail price.  This in no way affected the honesty of this review. We put at least 50-75 miles on trainers and 10-25 miles on racing flats prior to reviewing them. Currently I have 24 miles on my pair. My views are based on my extensive history in the footwear industry and years testing and developing footwear. If you are a footwear rep looking for footwear reviews or consultations on development, we are currently looking to partner with companies to assist, discuss and promote footwear models. Partnership will not affect the honesty of our reviews.

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