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ASICS Magic Speed 4 Review
By Matthew Klein and David Salas

The Magic Speed series has gathered a significant following since its introduction several years ago. Its unique ability to handle both training and racing as a plated shoe has made it popular with a variety of people. Version 3 was the update we were all waiting for as it brought a bouncy and propulsive FF Blast+ midsole that finally gave it the versatility into faster workouts and racing. As news surfaced that version 4 would feature FF Turbo, the thought that faster foams would be coming to more affordable racing shoes was exciting. Similar to the transition from the Magic Speed 2 to 3, the change from the Magic Speed 3 to 4 is just as significant. 

Asics Magic Speed 4
Price: $169.95 at Running Warehouse
Weight: 8.5 oz, 242 g (men's size 9), oz, 207 gg  (women's size 8)
Stack Height: M: 43.5 mm / 35.5 mm; W: 42.5 mm / 34.5 mm
Drop: 8 mm
Shoe Purpose: Plated Lightweight/Performance Trainer

Pros: Durable, Super-Stack Height, Snappy Ride for Uptempo Paces and Workouts
Cons: Medially Biased Midfoot/Forefoot, Firm for Stack Height


The ASICS Magic Speed 4 is a plated lightweight/performance trainer for those who want a maximal stack height but nimble shoe for for training workouts and longer races. A new maximal stack height and FF Turbo/FF Blast+ midsole, providing more protection, a slightly and more versatile ride. The upper features a lighter mesh that provides just enough room for both training and faster runs. A different shoe from previous Magic Speeds, Version 4 moves into the 40+ mm trainer space but still can move fast enough for longer races. 

: On Cloudmonster Hyper, ASICS Superblast

(To learn how a shoe should fit, check out our full podcast on fit by Matt Klein.)

Matt: The ASICS Magic Speed 4 fits me true to size in my normal Men's US size 10 if slightly short due to the tapered toe box. The fit is a combination between racing and training. The toe box is slightly tapered but opens in a normal-width toe box. The mesh material has some stretch to it and is normal to slightly higher volume. The midfoot is wider in the Magic Speed 4 but the solid gusseting from the thin tongue locks the foot down decently. I did not have to lace lock this shoe or tighten the laces much to get a secure fit. The heel fits normally to slightly snug in width with thin heel collar padding and a thin, mildly flexible heel counter. The counter is noticeable but has not bother my heel. Those with sensitive Haglund deformities should still approach with caution. The inner liner of the upper is mostly comfortable but I would still recommend socks. The rear portion of the shoe does not have a ton of padding and has caused some abrasions when wearing socks, so I would highly suggest using socks. The insole is not removable, so those hoping to use inserts or orthotics will need to look elsewhere or heat the glue to remove it. 

Typical Size: Men's US Size 10
Shoes that have fit Matt well: Saucony Guide 17, ASICS Kayano 30, Hoka Gaviota 5, Saucony Endorphin Elite, Nike Ultrafly
Shoes that have fit snug: Hoka Arahi 7, Saucony Kinvara 14
Shoes that have fit large: Salomon S/Lab Phantasm 2, Altra Timp 5

David: The ASICS Magic Speed 4 fits true to size in my Men's 9.5. The shoe has a streamlined feel to it and does not come off as overly wide or narrow in any regions. The shoe does taper some as it goes into the distal forefoot. The upper has decent volume for swelling accommodation. The upper material itself is surprisingly soft and comfortable for a shoe this light and responsive. The tongue is on the thinner end, and though I can feel pressure from the laces into the dorsum of my foot, I don't get any problematic biting. The laces themselves are on the softer end. There is a shallow heel counter that keeps the shape through the heel and is lightly padded. The upper is is unique in that it certainly feels like a performance upper, though is surprisingly comfortably soft. Upper security is also quite good and I did not have any major issues with foot translation. I would like the forefoot region to be a tad wider, though I did not have any issues from it in this model. Overall, this was a very good upper for the use. 

David's Typical Size: Men's US Size 9.5
Shoes that have fit David well: Nike Vomero 17, Saucony Ride 16, Puma Velocity Nitro 3

Shoes that have fit snug: HOKA Arahi 7
Shoes that have fit large: Salomon Aero Glide

Doctors of Running Checklist

Is This a Good Shoe for Walking: No
Is This a Good Shoe for Standing: No
Is the Forefoot Flexible: No
How Flexible is the Shoe: stiff
Is This a Good Heel Bevel: Yes
Recommended for Haglunds: No
Recommended for Sockless: No
Durability Expectation: Above Average


Matt: The ASICS Magic Speed 4 is a plated training shoe per ASICS but would be better described as a carbon-plated lightweight/performance trainer. There is a full length FF Blast+ midsole with a new FF Turbo foam insert in the midfoot/forefoot underfoot with a super stack 43.5 mm heel. The large amount of foam is firmer than I expected and not soft. There is some compression and bounce back at faster paces, but the ride is on the firmer side during easier efforts especially. This is partly due to the incredibly stiff, full-length carbon plate. I found the transition, especially in the forefoot, to be uncomfortably stiff. This broke in after one run, but the Magic Speed's transition feels better at faster paces when transitioning quickly through the shoe compared to slower running. There is an 8mm drop and that is exactly what it feels like. The heel is well-beveled and transitions smoothly. This moves into a stiffer midfoot where the lateral sole flare begins. This continues into a stiff forefoot with a large forefoot rocker. The rocker starts a tiny bit late (although more normal for a racing shoe), which combined with the plate makes for a stiff transition off the toes. The large lateral flare in the midfoot/forefoot is noticeable and creates a medial bias up front at slower speeds. At faster speeds, especially when landing farther forward, this compresses really well and provides a nice landing space. Those with a variety of footstrikes going faster speeds should do well in this shoe.

Pace-wise the Magic Speed 4 does best at uptempo-to-workout paces. The stiffness in the forefoot makes it slightly uncomfortable to use for easy and recovery paces (although it is getting better as the shoe breaks in). Picking up the pace dramatically helps the shoe transition better. I have found the Magic Speed 4 does great at uptempo efforts down to 10k paces. It can do shorter and faster efforts but there are better shoes for that. The snappiness, relatively lighter weight and slight firmness of the sole do make this an option for race distances from 10k to marathon. Those who do not do well with super soft super racing shoes may want to consider the Magic Speed 4 as the ride is firmer than the majority of super racing shoes. Its weight is comparable to several super racing shoes and has a similar stack height at a much cheaper price. Thus, this may be a more affordable race option for many people.

As with prior Magic Speeds, the durability is fantastic. I have 30 miles in my pair and have not made a dent in the outsole (even in my normal spot). Surface wise I would keep this shoe to roads and smooth terrain. The traction is solid for smooth surfaces but uneven terrain or softer terrain is not a great idea. As long as you keep to less aggressive surfaces, the Magic Speed 4 is a durable, stiff, super stack option for uptempo training, workouts and even as a race shoe for some.

David:  The ASICS Magic Speed 4 performed quite well for me. For how much foam there is, the initial step in was a little firmer than I thought it would be. Despite that, the shoe has plenty of cushion underfoot, having 43.5mm of FlyteFoam Blast+ and FlyteFoam Turbo under you in the heel and 35.5mm in the forefoot. The shoe has a similar feel to that of the Metaspeed Edge Paris through the forefoot, though a slightly different forefoot rocker profile. The shoe has a gentle heel bevel through the heel, but focuses very hard through the forefoot. The shoe is rounded sharply there and does give you a bouncy toe off that is couple with a pretty smooth roll. The traction underfoot is pretty good and has not given me any issues yet with road conditions. 

The shoe seems to like slightly uptempo to long distance racing paces. The Magic Speed 4 should fit as a solid training companion for the Metaspeed series for long distance races. The shoe can certainly run at slower paces, though it can feel a tad clunky through the midfoot and getting onto the forefoot. When the pace picks up that transition point smoothens out a little bit from the heel and midfoot and the bounciness of the midsole starts to come to life. The shoe is certainly a very neutral shoe, as the platform is not very wide for the stack height. I find that this is a shoe that can eat up road mileage, though it feels like it might be a tad unstable for much dirt usage.

(Learn more about stability in our full guide)

Matt: The ASICS Magic Speed 4 is a neutral shoe. There are some mild methods of guidance but these are offset by the narrow (especially in the midfoot) but tall platform. There are mild midfoot sidewalls that provide some mild central guidance. These are somewhat negated by the narrowed midfoot and tall stack height. There is some mild sole flaring throughout. The flaring in the heel and forefoot do help to keep a slightly more centered ride there. However, the lateral flaring at the midfoot and forefoot create a medial bias, which makes the shoe far more neutral. The stiffness from the plate does help add some torsional rigidity, particularly in the forefoot. Overall, the heel is neutral while the midfoot and forefoot have some medial bias.

David:  The ASICS Magic Speed 4 is certainly a neutral shoe. The shoe has a relatively narrow platform for a shoe that is at 43.5 mm of stack in the heel. There is some gentle sole flaring that works pretty well, though this has very neutral mechanics. The outsole traction is good and grips well on the road. The upper security is also solid and I have not found that I had any issues with foot translation in turning. I did have to tip toe a U-turn at one point due to the stack and platform, but for the most part the stability isn't too bad. The plate also helps keep the platform's shape and ride. Ironically, the shoe actually feels more stable when the pace begins to heat up, as the forefoot rocker and platform is the most stable region of the shoe. 

Thoughts as a DPT: When Should You Use Carbon Plated Trainers? 
By Matthew Klein

When carbon-plated super shoes first came to market, many people suggested (including us) that these were specific tools that for most people should not be used every day. Ironically, plated trainers were not new as many shoes and companies had already been using plates and shanks for years (Mizuno). Our concerns came about not just from the plate but also how incredibly soft these new racing shoes were and how different they were from everything else on the market. If one got used to this footwear type, then transitioning back to other traditional shoes could be an issue both comfort and injury rise. We were also concerned that this footwear type was so drastically different from normal biomechanics that some people could be at risk for certain injuries. Advanced footwear technology (AFT) does create some extremes of motion, including lengthening strides and often stressing tissues like the hamstrings, hip flexors, and deep hip rotators (Reynolds et al., 2023). 

Some of those concerns still exist but now a huge portion of the running footwear market has plates or stiffening agents, including traditional trainers. Although this is relatively normal in today's footwear landscape, the conversation now is when is it best to use extremely stiff shoes compared to more flexible ones?

The obvious answer is that it depends on the person. Some people do better in stiffer shoes while others do better in more flexible shoes (Mcleod et al., 2020). This may extend beyond workouts and even into training. Plates and stiffening agents add rigidity to the bending stiffness of a shoe and certain people's bodies do better with more or less stiffness. Stiffer shoes do tend to be more beneficial at faster paces, which is why many people tend to use them for faster days compared to slow days (Hebert-Losier & Pamment, 2023). Running at slower speeds in them may create stresses in certain areas as the force vectors and loading patterns change between normal and plated/stiff shoes. This could increase the risk of certain injuries as evident by recent case studies on an increase in bone stress injuries with AFT (Tenford et al., 2023). 

However, what is different from that research is there are now carbon-plated trainers that are designed for slower paces. The plates often feature larger curves and the sole geometries facilitate motion forward without the shoe even feeling stiff. These trainers should therefore be looked at as trainers that are stiff. So those who do best in stiffer shoes will do fine in these training shoes full time while those who do not do well in stiffer shoes may want to look elsewhere or use these shoes strategically. When it comes to lightweight/performance trainers, which often blur the line between racing shoes and trainers, most people should still use these only a few days a week for faster days. These tend to be more aggressive and similar to race shoes, so many people may want to utilize these tools for specific activities rather than all the time. 

So if you are someone who does best from a health/injury perspective in stiffer shoes, running in stiffer trainers and shoes all the time may be fine. If you do not do well health/injury-wise running in this shoe type frequently but you like them/they improve your performance, then you may want to use carbon-plated or stiffer shoes during strategic times throughout your training. If you plan to race in a stiff shoe, you do need to use a stiffer shoe at some point during your training. Key workouts, like long runs or speed workouts, are the most obvious times to use them if that activity is specific to your race. Once you have completed that workout, going back to a shoe with normal flexibility may be best for doing the bulk of your mileage/training in. For those who train in stiff-plated shoes all the time, just know that if you decide to switch to running in a more flexible or traditional running shoe, you will need to take time to let your body adapt back to this now new stimulus. If you give your body time to adapt, it should do fine. The issues arise when you try to switch or add stimuli too quickly for your body to adapt which is when injuries may occur. So if you figure out what works best for you and give your body time to adjust, you should be fine. 


H├ębert-Losier, K., & Pamment, M. (2023). Advancements in running shoe technology and their effects on running economy and performance–a current concepts overview. Sports Biomechanics22(3), 335-350.

McLeod, A. R., Bruening, D., Johnson, A. W., Ward, J., & Hunter, I. (2020). Improving running economy through altered shoe bending stiffness across speeds. Footwear Science12(2), 79-89.

Reynolds, S. R., Hastert, L. M., Nodland, N. M., Matthews, I. R., Wilkins, B. W., & Gidley, A. D. (2023). The effect of carbon fiber plated shoes on submaximal running mechanics in non-elite runners. Footwear Science15(3), 171-177.

Tenforde, A., Hoenig, T., Saxena, A., & Hollander, K. (2023). Bone stress injuries in runners using carbon fiber plate footwear. Sports Medicine53(8), 1499-1505.


Matt: I have enjoyed the upper changes from the Magic Speed 3 and the FF Blast+/FF Turbo midsole is growing on me. It fits far better but I am a little disappointed this has become more of a trainer than a racer. I can understand that the Metaspeed S4 has taken the place of the Magic Speed series as a racer, but that shoe isn't available in the US (yet). That said, it adds a super training option that actually may be more accessible as a racer for many people.

There are a few things I would still suggest improving. The toe box fit could use some adjusting to not feel so tapered. This does stretch somewhat but should be a bit more rounded if this is supposed to be a trainer. I would also like to see the sole width proportional to the height. The large stack height and relatively narrow platform, particularly the medial midfoot cut-out, does compromise stability. The extra lateral flare at the forefoot/midfoot may not be necessary and should be evened out between sides to keep for a more centered ride. I would also like to see that medial midfoot filled in a little more. This may improve the guidance and transition of this shoe especially at easier and longer efforts. 

David: I really enjoyed my time in the ASICS Magic Speed 4, though I do have some recommendations. My first recommendation would be to widen the fit of the forefoot a tad. I am happy with the volume and streamlined fit, though I do feel like the lateral aspect of the forefoot can put a little bit of pressure on the toes. I think the other recommendation would be to work on improving stability through the heel and midfoot region to make for a less choppy transition at easier paces. 


Matt: The ASICS Magic Speed 4 is a carbon plated performance trainer/potential racing shoe for someone with neutral mechanics who wants a super stack, stiff shoe that can handle uptempo paces to moderate to longer race distances. The ride will work best for those who want a stiff ride that is on the firmer side. The fit will work best for those who want a light upper with a slight forefoot taper and a wider midfoot. The Magic Speed 4 is still a great alternative to more expensive racing shoes and even features all the components necessary for a super trainer. It has now transitioned from the 5k/10k shoe that version 3 was to more of a 10k to marathon shoe given the weight increase. The incredible durability and pace versatility completely justify the $170 price tag as this is one of the cheaper carbon-plated faster shoes and the cheapest super trainer on the market right now. The Magic Speed series still fills a unique place in the ASICS line up but the exact spot has shifted to a longer-distance workout/racing shoe rather than a shorter one. 

David: The ASCIS Magic Speed 4 is a lightweight training (potential racing) shoe for someone looking to have a higher stack plated option for a large versatility of uses. The shoe has a prominent forefoot rocker and a very neutral platform to run off of. The shoe feels like it really falls into rhythm at controlled uptempo paces and can make for a great marathon training companion or even racing shoe for the right person. The feel of the foam is also a tad on the firm side, though still provides plenty of cushion. Those looking for that kind of experience should look into the Magic Speed 4.


Fit: B+/A- (Light upper with secure fit. Toe box more tapered than necessary)
A- (Carbon Plated Workout Trainer that does well at uptempo to faster workouts. A bit too stiff for easy runs)
Stability: B [Neutral] (Midfoot sidewalls and stiffness from the plate offset by medial cut out and narrow sole for how tall stack height is)
Value: A- (Extremely durable carbon plated shoe with decent uptempo pace versatility at a great price. Not the fastest shoe but likely more appropriate as a racing shoe for many people compared to true super racers)
Personal: B+/A- (Although I am disappointed in the weight gain, this shoe has been growing on me for workouts and uptempo runs while saving my expensive super racing shoes for race day. Not quite stable enough for longer efforts for me though)
Overall Design: B+/A- 

Fit: A- (Dialed in fit with good security and comfort, forefoot could have a tad wider fit)
Performance: A- 
(I really enjoy this shoe at slightly uptempo paces and beyond. I can do easy paces, though I would like for the heel and midfoot to be cleaned up a tad.)
Stability: B (Upper security good, forefoot stability good, though midfoot and heel could be refined for smoother transitions)
Value: A (You can beat this into the ground with good variety of uses.)
Personal: A- (Great long run shoe and training companion, just wish it would be a little smoother at easy paces.)
Overall Design: A-


Asics Magic Speed 4
Price: $169.95 at Running Warehouse

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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, Santa Barbara, Danbury and Stevens Point areas, we am currently taking clients for running evaluations.

***Disclaimer: These shoes were provided free of charge in exchange for a review.  We thank the people at ASICS USA for sending us a pair.  This in no way affected the honesty of this review. We systematically put each type of shoe through certain runs prior to review. For trainers and performance trainers, we take them on daily runs, workouts, recovery runs and a long run prior to review (often accumulating anywhere from 20-50 miles in the process). For racing flats we ensure that we have completed intervals, a tempo or steady state run as well as a warm-up and cool down in each pair prior to review. This systematic process is to ensure that we have experience with each shoe in a large variety of conditions to provide expansive and thorough reviews for the public and for companies. Our views are based on our 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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