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 adidas SL20.2 Review
By Social Media Manager Bach Pham

Adidas fans surely have a love/hate relationship with the brand. From the days Boost was released to the final days of Boost, to the various models that have come and gone quietly in the Adidas line, it can be hard to totally grasp what Adidas is doing. The thing is though, there are just enough good Adidas shoes that you can't simply ignore what they are doing. When the Adidas SL20 (SL standing for "Super Light") came out last year, it provided a snappy workout trainer that for some fell into the lightweight training category. While that proved to be an underground hero in 2020, especially for the price points folks were finding it, Adidas returned in 2021 with the SL20.2, which offers a fairly big change from its predecessor that we'll dive into for this review.

Specifications adidas SL20.2 (per Running Warehouse)
Weight: 8.4 oz (men's size 9) , 7.5 oz  (women's size 8)
Stack Height: 31 mm heel, 21 mm forefoot
Drop: 10 mm
Classification: Daily Trainer


The Adidas SL20.2 running shoe returns in 2021 with one big change: a thicker slab of Lightstrike midsole. The change brings a bit more versatility to the shoe as an everyday daily trainer. The upper gets some minor changes, adding a raised heel that matches the new Adizero lineup. At $110, the shoe is a solid, basic offering that will fit a lot of runner's needs and can easily slide into many runner's shoe rotations for anyone who likes a slightly firmer, lightweight trainer that can do a little bit of everything.


The Adidas SL20.2 fits almost true to size, but is a bit short in volume around the toebox. I would recommend true to size for those with narrow to standard feet and sizing up if you have a wide foot or are in-between your next size up. More than prior Adidas like the Boston 8 which had a narrow fit throughout, the SL20.2 has slightly more standard width throughout. The heel collar has a medium height which sits behind my ankles. I had no issues with rubbing, but anyone who is sensitive to a higher heel collar will want to take note. There is light padding in the heel counter that made the fit comfortable, and I had no issues lacing down the shoe even without a runner's knot to get a good fit. The heel counter is moderately rigid and does a good job of holding the foot down without any trouble. The engineered mesh upper is absolutely nothing amazing, doing just fine of a job with breathability and lockdown. There's just a little width for me in the forefoot to give my foot some room, which added to the daily trainer vibe of the shoe. I will say the upper around the toebox is slightly unstructured, folding onto my toes when pressing down which I felt on really long efforts.

If there was one issue I really had that stood out, it was with the external heel counter. It wraps around the heel and extends into the midfoot where I had the most issue with it. I felt this on my first run prominently, as if there was something pushing into the medial side on both feet. This feeling was much more mild through ensuing runs though as the shoe broke in. It never hurt or irritated me though; it just felt present. The upper on the medial side is also fairly minimal. Anyone prone to unstructured midfoot uppers may have issues here as the upper thins into the midfoot mildly and doesn't provide a lot of support. The SL20.2 otherwise is a surprisingly comfortable shoe on foot that carried me through many runs without issue.


While the SL20 version one was a thinner, "Super Light" workout trainer, the SL20.2 redials the formula with a thicker slab of Lightstrike foam. This change adds a daily trainer element to it which I really enjoyed. Unlike the completely revamped Adizero series this year that added everything from Lightstrike Pro to Energy Rods in the various models, the SL20.2 is refreshing in its simplicity. There's no torsion system, no Energy Rods, nor hints of Lightstrike Pro; just a slab of Lightstrike midsole that's ready to go out of the box.

Despite being a huge stack visually, the shoe feels like a really solid daily trainer that runs very naturally. There's a lot of versatility here, whether you want to take the shoe on easy runs or pick up the pace for some tempo efforts. While it does not pop as much as the original, when you pick up the pace the Lighstrike feels decently responsive, offering easy turnover. The shoe itself has some mild flexibility in the forefoot which is hard to find in the Adidas line now between torsion systems and Energy Rods in many of their shoes. While most of my runs were easy, I also enjoyed taking it on a moderate tempo run. The Lighstrike midsole responds nicely - really nicely in fact - when moving faster and I really enjoyed the natural roll of the shoe. There's a very slight heel bevel in the SL20.2 that helps keep it moving soundly without feeling clunky in any way. I would not pick the SL20.2 over a true workout shoe if given options, but it can handle it when called for.

Having run in the Boston 8 model which first featured Lighstrike, it was really fun to just be able to purely test Lightstrike without any torsion system or alteration in the way. It's a good foam for what it is, and resilient. I was also able to take the shoe out on a longer, near two-hour effort and the shoe felt protected the whole time.

The ride itself sits somewhere almost right in between soft and firm, leaning slightly towards firm. There's enough height that you aren't feeling the road too much, but firm enough that you are able to push off and get some feedback. While the Continental outsole adds some good grip, the surprising Adiwear that is paired with it contains a diamond lug-like pattern that offers even more traction, running through wet weather well and gripping the road in general with ease. I was also able to take it on light dirt and grass with decent success. After 40+ miles, I have yet to see any distinct wear on the shoe and have confidence this will run 300 miles without issue.

For those looking for the snappy workout shoe that it was prior, you might be disappointed, and if you are putting it in the lightweight category up against things like Mach 4 or Kinvara which sit in the 7 oz category you might think it's just a little heavy, but if you re-frame it as a daily trainer compared to shoes like the Nike Pegasus 38 or Saucony Ride 14, or better yet Reebok Floatride Energy, you have a compelling workhorse that can handle a lot of your activities in a 8.4 oz package.


The SL20.2 is a neutral shoe. However, the external heel counter wrapping around the heel and partially through the midfoot does a nice job of cradling the foot and helping some minor guidance. While not a firm ride per se, the slab of Lightstrike has enough firmness that it helped provide a solid base to land on. I have flat feet and often can feel if a soft foam compresses too much, but I found the SL20.2 to hold it's shape well and not be an issue. The outsole helps provide additional support underneath the  midfoot. The forefoot has a slightly wider base than shoes like the Nike Pegasus which helps with landing comfortable at higher speeds.

The shoe loses points in the slightly thin upper through the midfoot on medial side of the SL20.2. Despite a minor "sidewall" via the external heel counter that wraps into the midfoot, you may be prone to some collapsing into the upper if you are someone that's foot tends to want to roll inward heavily. The firm slab of midsole underneath does counteract it slightly, but at the end of the day this is a neutral shoe overall.


2021 featured a total revamp of the Adizero line for Adidas, leading to a bit of shift in where different shoes are placed. While some of the changes were controversial (see Boston 10), these changes did help actually work to simplify the line somewhat. Last year, the Adidas line looked somewhat like this:

Adizero Adios - Non-plated racer, workout trainer
Adizero Pro - Lower profile racing shoe
Adizero Adios Pro - Super shoe
Adizero Boston - Daily trainer/workout trainer
Ultraboost - Max cushioned trainer
RC - Lightweight workout trainer
SL20 - Workout trainer

What you ended up with was a lot of snappy shoes that almost overlapped in what they were doing. Effectively, several of the shoes were subtle variations of the other,. 2021 helped realign the brand to focus on more "pairings" which we have started seeing with other companies.

Adizero Adios 6
- Workout trainer
Adizero Boston 10 - Training companion to the Adios Pro
Adizero Adios Pro 2 - Super shoe
Ultraboost 21 - Max cushioned trainer
SL20.2 - Basic daily trainer
RC3 - Lightweight workout trainer

The biggest difference between the two years is that the pairings in the Adidas line for 2021 makes a lot more sense down the line regarding the role of each shoe and where it slots among one another. The one loss in the changes may be for those who enjoyed the low profile Boston of yesteryears, but as far as creating more distinctions and less overlap in their line, Adidas did a nice job of moving in a more focused direction for 2021.


Fundamentally, I really enjoyed the SL20.2 as is. It provides the Adidas line with a fairly simple, effective daily training option that will suit many. If subtle changes were made, I'd like to see the medial side of the upper slightly more structured and the sidewall retooled to help be less invasive into the midfoot. I would even go as far as suggest reducing the external heel counter to just the heel area to keep that cradling effecting, while focusing on just providing a more structured upper to hold the midfoot, similar to the excellent upper on the Adios 6 right now. I would also add a touch more toebox width to accommodate runners and some structure to prevent folding in around the toes. Regarding ride, the shoe has a fairly natural roll as is, but adding a slightly more aggressive bevel in the heel would really smooth the ride even further and speed up the ride, while also reducing weight even further.


The Adidas SL20.2 fits nicely in the Adidas lineup as the most no-frills, modern daily trainer that's best for easy runs, long runs or light workouts. Adidas fans will have some terrific ways they can pair this shoe in their lineup as an everyday trainer. You can pair the Adios 6 as your speed day shoe for a really fun one-two combination that can handle a million runs. You can add the Adios Pro 2 if you want a super shoe that can do some of your hardest long efforts along with race day while the SL20.2 handles the majority of your lighter efforts. You can even pull out the original SL20 to act as your workout trainer while the SL20.2 handles your daily running.

At $110 full price, the shoe comes in at an excellent deal that will likely only get better going into the holiday season. It has a little more stack and protection than many basic budget trainers like the Brooks Launch or Reebok Floatride Energy, which only adds to its versatility. For most everyday runners, this will be able to do just about everything you need and acts as a solid beginner shoe for neutral runners as it can handle a variety of distances along with workouts just fine. For those who are more seasoned in running, it's basic for sure, but a solid ride that's very easy to pair with more exciting shoes in the market today, whether in or out of the Adidas line.


Fit: B- (Fairly standard fit throughout, which some unstructured parts of the medial side in the midfoot. Wider feet will likely need to size up a half size. Slightly small toebox and unstructured upper around forefoot was slightly tight at the end of longer efforts)
Performance: B+
(Added Lightstrike offers great versatility for daily training, while still being fairly responsive for workouts)
Stability: B (External heel counter and fit cradles foot well, while firmer midsole helps keep foot from overly collapsing, but weakly structured medial side still makes the shoe best for neutral runners)
DPT/Footwear Science: B (Fundamentally, the SL20 is one of the simpler shoes in the Adidas lineup, stripping away technology to provide a back to basics experience with a higher stack midsole)
Personal:  B+ (I enjoy the SL20.2 for its simplicity. It's really nice to just grab and go in a hurry. The versatility of the shoe is welcome and it's really nice to just have a plain shoe out of Adidas without any frills to really see how Lightstrike feels on foot)
Overall: B (More than capable daily trainer. Those looking for the snappy workout trainer it was last year will want to check out the Adios 6 if you are looking for that poppy ride in the Adidas line. If you want a simple trainer that can handle your daily runs and pick up the pace some days, this is a fine option)

Find the adidas SL20.2 at Running Warehouse here. Using the link to purchase helps support Doctors of Running. Thanks so much!

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Compare Daily Trainers
Nike Air Zoom Pegasus 38 Review - The classic Nike trainer features an upper update which solves much of last year's issues
On Cloudflow 2.0 Review - A similarly versatile trainer from On. A tighter construction and firmer ride for those who likes a shoe that rolls along nicely
Reebok Floatride Energy 3.0 Multiple Tester Review - Forget the $100 aspect of this shoe. The FFE3 is just a solid everyday trainer with a good ride and no frills upper
Saucony Ride 14 Review Multiple Tester Review - An easy recommendation for anyone looking for a reliable daily trainer thanks to a good foam and generous fitting upper

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Hoka Rincon 3 Review - New outsole rubber and a lighter upper highlight the latest Rincon

Thanks for reading!


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Bach Pham MS
Marketing and Social Media Manager
Master of Arts in Cultural Anthropology

Bach Pham is a 140 lb male with PRs of 23 5K, 52 10K. He typically runs between 25-35 miles per week at a variety of paces between 8:30 (tempo) -10:00 (recovery) min/miles. He typically prefers shoes that provide some mild to firm cushioning underfoot that is lightweight and responsive. Currently his goals are to complete the half and marathon distances.

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.

***Disclaimer: These shoes were purchased by our team!  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 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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