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As the world of fitness continues to evolve, most people are moving to a more “hybrid” style of training—I credit some of this to the growth of HYROX—and shoes like the Inov-8 F-Fly are a nice option.
For context, the Inov-8 F-Fly is designed as a hybrid shoe that works well for anyone who plans to run and lift in the same workout. It’s the most responsive in Inov8’s current training shoe lineup, whereas the F-Lite is the “do-it-all” cross-training/CrossFit shoe, and the F-Lite MAX is the most stable trainer built for lifting and CrossFit.
I’m the type of athlete who regularly tackles pre- and post-workout miles or programming intervals into my sessions.
Last week, I used the F-Fly to run an aggressive 5k and squat 325 lbs. Then, I used it for CrossFit Open workout 24.1, and in all of these settings, it was an exceptional shoe—which, to be fair with the squat sets, surprised me.
Inov-8 F-Fly
Pros
- POWERFLOW PRO midsole is highly responsive
- Good option for moderate strength training
- Wide toe box is great for toe splay
Cons
- Not the best for narrow feet
- May lack for CrossFit-only lifters
- Upper lacks for explosive lateral work
Best For
- HYROX-Style Training
- Runs From 1-5 Miles
- Strength Training (best up to 415 lbs and below)
- Cross-Training Workouts
- Workout Classes
Specs
| Heel-to-Toe Drop | 4mm |
| Weight | 9.85 oz |
| Width | Wide |
| Lifting Threshold | ~365 lbs |
| Run Distance Threshold | 1-5 miles |
My Top-Level Thoughts
The Inov-8 F-Fly is best suited as a shoe for running 1-5 miles, lifting, and cross-training. My favorite workout to use this shoe in thus far was a session where I trap bar deadlifted 405 lbs, hit kettlebell snatches, farmer’s carries, and then a 2-mile steady state run.
For that type of workout, I loved this shoe. It had the perfect blend of bounce for my dynamic work and running but enough stability for my strength sessions. This shoe won’t be as stable for lifting as shoes such as the Dropset Trainer 2, but it can hold its own.
I also appreciate that this shoe feels like Inov-8 is getting back to its roots. They initially grew in popularity for building shoes that had a more “minimalist” and flexible vibe, and this shoe fits that vibe, in my opinion.
If you’ve been looking for that “do-it-all” cardio and lifting shoe, these are good bets. Remember, as with any hybrid shoe, this model tries to exist in multiple worlds and will lack some hyper-specific features like stability for lifting and durability for CrossFit.
As in, I wouldn’t make this my “only” CrossFit shoe, but if I’m tackling a WOD where I know running is programmed, then these will come with me in my gym bag. The F-Fly gets a nod of approval from me as a strong hybrid training shoe.
Jake, should I buy these or not?
I’ve gone through many hybrid shoes, and the F-Fly is one of the first pairs I’ve sat in, and I’ve been like, “Finally, a shoe that does it all.” Far too often, I find “hybrid” shoes lack the ability to truly excel in both weight lifting and running verticals. The minimalist feel of this shoe while still giving you cushion and responsiveness — it’s a “chef’s kiss.”
- Shop the Inov-8 F-Fly (buying here supports my small business/content!)
How I’ve Tested These Shoes
For the Inov-8 F-Fly, I’ve made a conscious effort to truly push this shoe in the hybrid vertical. Sure, I train like that normally, but I wanted to really hammer some good runs in this shoe to assess its overall comfort.
Training Tests Summary
- Heaviest Lift In These So Far: Trap Bar Deadlift 455 lb x 6
- Longest Run In These So Far: 5-Miles (7:30 – 8:30 mile pace)
- CrossFit Tests So Far: Open Workout 24.1, Linda
- Total Miles Walked: 30-miles (per the publishing of this review)
Why the F-Fly Surprised Me for Lifting
Of all my tests, the F-Fly’s lifting performance has been the most surprising. Generally, a training shoe marketed as “hybrid” falls short of truly pushing weights in the gym—here’s looking at you On Cloud X 3.
For squats, I’ve trained up to 325 lbs in this F-Fly, and it did a pretty good job. At this weight and above it, you will notice the POWERFLOW PRO midsole compresses a bit, but it never feels unstable or as if I lack balance when training.
Because this shoe has a wider sole and a “lower” stack height compared to other “hybrid” workout shoes, you can push higher intensities in this model without feeling like you’re squatting with normal running shoes.
As for deadlifts, I pushed this shoe’s thresholds up to 455 lbs with a trap bar deadlift of 6, and it felt pretty good. Again, you’ll definitely feel the midsole compress a bit, but not to the point where I was concerned.
For a funny anecdote, I just used the NOBULL DRIVE for the same tests to compare the two since they’re both hybrid shoes, and never again. It’s night and day, and the Inov-8 F-Fly is the clear winner of the lifting tests. The DRIVE felt like I was lifting on pillows.
In the context of general strength workouts, these should work perfectly fine. For example, if you need a model for hitting free weight sessions, some moderate machine work, and hypertrophy sets, you’ll like these.
My Thoughts On Using This Shoe for CrossFit and Cross-Training
For cross-training and CrossFit, I think the Inov-8 F-Fly will work exceptionally well for some workouts but may fall short for others. To elaborate, it really comes down to your weekly training breakdown and what you want these for.
In the realm of cross-training, I found the F-Fly to work best for workouts where I was doing sled work, kettlebell circuits, and explosive exercises like broad jumps and box jumps — think front-to-back explosive exercises and movement.
This shoe can be used for lateral work. However, its downfall is the lack of rigidity around its toe box and lateral midfoot. You may experience some spillover with this shoe if you’re doing harsh cuts and exercises like skater strides.
I also think narrower feet may find that they slide around in this shoe for this performance context. This model doesn’t have the lowest profile upper, and I could definitely see security being an issue for narrower feet in this training context.
For CrossFit, this shoe will slap when you’re running in WODs. It’s stable enough for lighter-weight deadlifts and squat thrusts, and it works well for interval runs, double-unders, and burpee box jumpovers.
Basically, wear these on WODs where you know you’re not rope climbing or going crazy with your strength work. I would not wear these for tackling heavy clean & jerks and snatches, or maxing out/testing my squats and deadlifts.
The Type of Running and Walking I’ve Liked the F-Fly Best For
The reason I like the F-Fly for HYROX-style training is its ability to excel in short runs. Thus far, I’ve run up to 5 miles in this shoe, and where I liked them best was for intervals and 5k runs.
For this running style, I’m primarily using my forefoot to move quickly, and I enjoy the responsiveness of the POWERFLOW PRO midsole in this model. It feels lively and bouncy despite having a more “minimalist” vibe than normal running shoes.
This construction feature will be well-suited to barefoot shoe lovers and those who like lower-stack height running shoes. Even when running slower and with the heel striking a bit, I didn’t find this shoe too uncomfortable, which was also a nice surprise.
Would I use this shoe for tackling marathons and high-volume running weeks? I would personally not, but that’s because I like plusher shoes for this running style, as I feel less beat up from using them when tying together my running and strength workouts.
I’ve thoroughly enjoyed this shoe’s performance and comfort while walking. The outsole has a good level of tread, and it’s comfortable for long walks and being on your feet all day. I wear mine looser to slip on when wearing them for walking.
If you’re like me and like training shoes that you can wear casually and comfortably all day to run errands, walk the dog (or kids!), and even travel with, you’ll appreciate the F-Fly’s comfort.
Construction Details
The construction of the Inov-8 F-Fly is one of my favorite things about this shoe. It’s simple, but it ticks all of the boxes you want from a good hybrid workout shoe.
Outsole
The outsole features a full rubber tread patterning with 2.5mm thick lugs. These lugs did a good job of biting different gym surfaces like turf, rubber gym floors, and even wooden platforms.
Outdoors, when running, I’ve also enjoyed how these lugs have bit concrete, grass, and light gravel. These are all surfaces I’ve encountered with these shoes, running and walking in them.
There’s a meta-flex split at the forefoot, which tends to be standard for Inov-8 shoes, and this gives the outsole a little more flexibility. This model also features ROPE-Tec at the midfoot. If you do end up using this shoe for rope climbs, this feature helps a ton.
Midsole
The POWERFLOW PRO midsole is the star player of this shoe. Inov-8 uses their POWERFLOW midsole in most of their training shoes. For example, the Inov-8 F-Lite 235 V3 and 260 V2 use this midsole but its much denser.
The midsole depth of this shoe is 10mm in the heel and 6mm in the forefoot, giving this shoe a 4mm heel-to-toe drop. Compared to normal running shoes, the F-Fly’s midsole stack height is a lot lower, and this contributes to this shoe’s articulation and flexibility.
There’s a little toe spring in this shoe and heel bevelling. I never found these features to take away from this shoe’s lifting performance because they’re not overly aggressive.
Upper, Tongue, and Laces
The upper is primarily composed of a lightweight mesh. This mesh also features a 3D-printed construction, which helps contribute to this shoe’s durability and support when running and doing explosive workouts.
I like the breathability of this shoe’s upper, and I think the mesh makes it a good pick for hot climates and outdoor workouts. This shoe utilizes five eyelets, with a sixth eyelet for lace-locking.
The tongue is gusseted and built with a padded mesh. I have yet to experience tongue security issues in this shoe, even when wearing it looser. For a hybrid-focused shoe, Inov-8 nailed it with this model’s upper construction.
My Sizing Advice
I think for most lifters and athletes the Inov-8 F-Fly should fit true to size.
This model’s length is a smidge on the shorter side compared to my other size 10 shoes, and they have a wider forefoot width. Size the F-Fly like your other Inov-8 shoes if you own their shoes already.
For context, I wear a size 10 in all of my training shoes. I have an E-width foot with a normal arch. This shoe fits my foot like a glove, and I even have additional room in the forefoot for toe splay.
Additional Sizing Thoughts
- To elaborate, for medium and wider feet (E to EE-widths), you’ll be fine going true to size.
- If you have narrow feet, you may want to look into models that better suit your foot anatomy.
- If you have wide feet and you find you’re normally hitting the end of your toe box, size up a half-size.
If you have additional sizing and fit questions about the Inov-8 F-Fly, drop a comment below, and I can help you out. Let me know what shoe you currently wear and in what size, so I have some context.
Final Verdict
Inov-8 came out swinging the Inov-8 F-Fly. The hybrid shoe market is still what I would call in its infancy stage, or at least that’s how it feels as the hybrid training style continues to get more popular.
If you’re a HYROX athlete, a CrossFitter wanting a more runnable training shoe, or someone tired of using multiple shoes for training and wants a singular model for running and lifting, the Inov-8 F-Fly can be a great choice.
If you have additional questions about this shoe, drop a comment below, and I will help you decide if these are right for you.
Nick
I run the 235’s V3, my favourite all round training shoe (nanos/metcons for the heavier lifting wods). Only just found out the 235’s are gone.
Are these going to be the best replacement? They look like they have a similar build to the 245’s?
Thanks for your reviews – almost ordered the F-lites before I read this fly review. Have these on the way, just trying to gauge what shoe I’m really in for.
They’ll be a little more plush than your 235s. If you want a bit more density, go normal F-Lite, which you already did! Let me know how the F-Lite works and if you want to try these, hit up That Fit Friend Shop and I’ll cover your returns for an easy trial!
TL
I’m keen to get an all-rounder for short distance cardio, walking and weightlifting. I also have a preference for (almost) barefoot running, having worn Vibrams at the gym for years. Would these be a good replacement? I’m a US10 size for the Nike Free Metcon 6 so would the same size for these work?
These will def have a bit more stack than your Vibrams, but they’ll feel more minimalist than most runners and trainers. I’d give em a go and see! If you go through That Fit Friend Shop, I’ll cover your returns so you don’t have to stress any financial loss in giving them a go.
I’d size up a half size and go with a 10.5!
TL
Thanks for the reply! Appreciate it.
Welcome!
Jake
I workout at home, mostly following Apple Fitness+ and Fiit HIIT, rowing and dumbell strength workouts plus very occasional short treadmill workouts when mixing it up. I currently wear the On Cloud X3 size 10 mens US for these workouts and am looking to update them. Would you recommend the F-fly or something else? If so, what size would you suggest?
For additional context, I sometimes feel the X3s are a little short when doing exercises with a plank-type position as my toes touch then end but they otherwise seem OK. For longer treadmill workouts, I have Hoka Mach 6 size 11 men’s US and am also usually a size 11 mens USin other shoes (Nike and Asics; a running store suggested Asics were a pretty good match for my feet when they did a scan).
Thank you!
Hey fellow Jake!
I’d give the F-Fly a try and I’d go for an 11 in them, potentially an 11.5. They run a half-size short for some foot anatomies, so that may be the safer call. If you go through That Fit Friend Shop and I’ll cover your returns if you need to make any!
Jake
Thanks for the reply. I tried these half a size up and they still felt too short lengthways. I’m now also looking at the Tribase Reign 6 or Free Metcon 6 as they’re similar prices with offers. What are your thoughts on these for my needs? Or do you think it’s worth trying another half size up on the F-fly?
I would try going up one more time in the F-Fly. I actually just worked with somebody in person who has to do the same and when they want up a full size it was a money fit. I’d try that first before going back to the drawing board
Jake
Thanks for your help and advice. I was able to very briefly try these three shoes next to each other and thought I’d share my experience/opinion. The F-Fly were nice, light and comfortable but I need as much help as I can get with stability and they weren’t stable enough when doing dynamic weighted moves like lunges (so I didn’t bother trying to size up). First impressions of the Free Metcon 6 were good. Plush and cushioned forefoot for HIIT moves and good stability. Then I realised the sizing was off. Length was fine but there was a big flap of material at the side when tightened because of the gusseted tongue. My feet were also slipping around during dynamic lateral moves. The Tribase Reign 6 were exactly what I was looking for stability-wise and they fit great. They’re the least cushioned for HIIT but seem good enough (especially on my soft home gym floor, which might have exaggerated issues I had with the other shoes) so they won out for me (although the cushioning doesn’t feel too different to my On Cloud X 3). Helps that I found them at a bargain price so can get something else for HIIT later if needed.
Love it! I appreciate you sharing feedback. Def helps others who have been debating these models!
Sammie G
Hi! Looking for a shoe that has a bit of cushion, due to shin splints while doing double unders and box jumps/over, running. I CrossFit 4-6 times a week. These, whatever shoes I find, would be my primary shoes for wods and some strength, lifters for other strength. I currently wear Reebok nano 9’s and Nike metcon 4’s. I tend to like a wider toe box so these check that box. Struggling with the transition from the typical flat cross training shoe to something to help with shin splints. Any other suggestions would be great!
Thanks!
Hey! I’d honestly start with these to see if they work. They’d be my first pick for you based on your feedback. If they’re a complete no-go, then we could try other options. Go up a half-size size in them if you have a medium/wide foot!
If you go through That Fit Friend Shop and they don’t work, I’ll cover your returns, btw. I try to help out the community that support the brand/content as much as I can!
Dhrumin
Thanks for the review. I just ordered these and waiting for them to arrive. However, I wanted to know if they are also good for wearing outdoors too as a daily war? I was hoping to get a shoe for everyday wear along with gym. I mainly do HIIT training (Orangetheory) and might go to crossfit in the future.
Yeah, they should be solid! I’ll rock mine for that and they work great. White can get dirty faster, but that’s stereotypical for most models!
Orian Hernandez
Great review. I am interested in a transition shoe with wide/anatomical toe box that is suitable for indoor sports like volleyball and handball (at recreational level). I see that you do not recommend them for court sports but I did not see the reasons why.
Upper is too lax to give you lockdown for harsh cuts and sport-focused movements, imo. You’ll want something that will give you better lockdown when moving explosively laterally.
Dhrumin
Thanks for the review. Just bought these base on your recommendation. I do mainly Orangetheory workout and might move to CrossFit.
Awesome! Thank you for checking it out and please keep me posted. The F-Fly has been a sick model for training.
Mervyn
Hey Jake
Does this have a flat sole? Or is there any sort of arch in them?
There’s a tiny bit of arch in em, so if you need a flatter feeling shoe I’d prob pass on this pair or buy em through Amazon so an exchange/return is easier!
Clément
Hey there,
Would you recommend those vs the F-LITE FLY G 295? Because I have the impression they are more or less equivalent in the same areas…
I am doing a lot of Crossfit, and own a Nano x4 but don’t really like the feeling when running outside. And I am preparing for my first Hyrox, for which I don’t really know which pair of shoes to pick (I have running dedicated ones).
Looking at the return policy in EU of Inov8, I want to make sure I order the right one… 🙂
Thanks for the advise !
Hey Clement!
For your context, I’d go F Fly because the rubber outsole will give you more grip for HYROX asks like sled work. Think they’d be a safer bet all-around. Fly G 295 has that rubber/foam-feeling sole so its grip does deteriorate faster over time!
Ari Sherwood
Would you say these have an anatomical toe box (i.e. set up for toe splay and big toe to spread out), or just a wider one? I’ve found the anatomical toe box of the Haze trainers to my liking but the sizing is always a bit off with them, and I’m wondering if these would be a good substitute.
Thanks!
Hey Ari — More anatomical for sure, as in, more boxy and wide comparatively speaking. They’ll be a good sub if your goal is that hybrid-focused model, but they won’t have the exact same dense as the Haze. Can still go heavy AF in em, though. If you want, hit me on IG and I’ll send you a comparison video tomorrow of the two!
Robert Rebori
Hey, Jake,
How durable is the F-Fly’s outsole in comparison to the Haze Trainer’s?
Thanks!
Should be more durable! The rubber’s lugs are more aggressive and even on high volume concrete use this shoe has done a good job.
Steve Hoover
Love this shoe! Perfect for all around training
Slept on model for sure!