I’ve been holding off on writing my review for the Innov8 Mudclaw 300. I wanted to run a 20 mile off-road race called ‘the... Innov8 Mudclaw 300 5

I’ve been holding off on writing my review for the Innov8 Mudclaw 300. I wanted to run a 20 mile off-road race called ‘the Grizzly’ to give them a final proper test. Whilst I’ve done plenty of training runs in them, sometimes you need a race to push the limits. Thankfully the ache in the legs is now fading away and I can honestly say, the Mudclaws didn’t disappoint. I came 9th overall and I guarantee I would have lost a few more places if I hadn’t hit the downhills quite so hard. I’ll try to get into the details of what makes these trainers quite so good for off-road racing and hopefully you’ll be able to figure out if they’re right for you.

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The Innov8 300’s come in two colours – blue and red (shown here) or red and black. Both look pretty smart, alas this trainer was never meant to be kept clean.

Sizing wise, the trainer offers two versions, a standard fit and a precision fit. Innov8 advise that you will likely need to go up half a size for standard fit. The main difference between the two is the toe box with the standard fit being wider. Take a look at the innov8 innersole over the top of a Brooks Cascadia trail shoe innersole. (same x-rayshoe size).

DSC_0040 (1)Don’t take too much notice of the extra blue area around the arch section. This folds up the inside of the Cascadia shoe which adds a bit of comfort in pronation. Despite this, you can see the Innov8 has a slightly more streamlined cut. The shoe is tighter through the ankle area and around the heel. This helps to lock the back of the foot into the shoe. If you wiggle your foot from side to side, your ankle doesn’t move around in the same way as other running shoes. This makes your footing more secure over unstable ground where you tend to have more lateral movement.

The Mudclaw is a little narrower in the forefoot but you won’t feel this so much at the toes, rather at the metatarsal area. That’s the bony bit on the inside of your foot seen in the x-ray shot, and in general, the widest part of your foot. If you feel this is wide on your feet, opt for the standard fit. The circumference of this part of my foot is 260mm. If your foot is 265+ you’re probably best opting for the standard fit model.

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In overall sizing terms, I find the precision fit runs a 0.5 or 1 UK size bigger than your normal everyday shoe/boot. For me the 11.5 fits well. My heel to toe length measures 287mm and generally, I find the sizing runs the same as Brooks. This is half a size smaller than my Nike 5.0’s where I find myself at UK12. As with all running trainers you need to ensure you’ve got a little room to accommodate the swelling that happens to your feet as you run. There’s obviously no substitute for actually trying the trainer on, and supporting your local running shop is a good thing. That said, it can be tricky to find Innov8’s and I think it can sometimes be a shame to pick a brand based purely on the shops availability.

The Mudclaw 300 gets its name from its weight. A standard size 8.5 model being 300g. That’s relatively mid-range – not too bad for a trail shoe. To give it a bit of comparison the Saloman Speedcross comes in a little heavier at 310g and the Fellraiser a touch lighter at 275g. You can go a lot lighter, even in the Innov8 range, with the ultra minimal  X-talon 190 weighing 190g. However, you sacrifice a lot of support and cushioning if you put a shoe on that type of diet. This was evident to me a couple of years ago when I tried to do the majority of off-road racing in the lightweight x-talons and ended up injured. I now use them for races under 10k and sparingly, whereas the Mudclaws I find comfortable over any distance.

DSC_0026 (1)The Mudclaw on a size UK 11.5 weights app 335g

The Mudclaws have a drop of 6mm (the drop from the heel to the toe), which I’ve found quite comfortable even on long runs. The 190’s have a drop of 3mm which feels like a racing flat. The Salomans are slightly bigger drops with the Speedcross being 11mm and the Fellraisers 10mm. What does all this mean? Well it really depends on learning this for yourself over time as the biomechanics of everyone’s stride is different. The rough guide says you are more likely to land mid to fore-footed in a shoe with a lower drop. Shoes with a larger heel drop encourage heel striking. There’s a lot of debate but generally mid foot striking seems to be the way to go. Saying that, I land mid footed in a 12mm drop or a 3mm drop, but I’ve tried cushioned shoes with minimal drop in the past, and not got on with them. There’s other factors such as stack height, foam density, medial support etc which no doubt interact with the drop, so it’s difficult to always pull out one factor. Saying that, the Mudclaws with 6mm are a nice middle ground allowing you to feel close to the ground without being extreme. I don’t feel the same stress on my Achilles or calf muscles when I run in these compared to lower drop trainers. Those used to the higher drop on shoes like the Salomons may want to spend a bit of time transitioning over to the lower drop but honestly, the 6mm drop doesn’t feel extreme.

2arrowsInnov8 use a system to categorise the support and heel/toe drop offered in their trainers. Mudclaws sit bang in the middle with moderate support and a 6mm drop.

The uppers of the shoe feel super strong. There’s plenty of stitching and supportive silicone strands which run up the side of the trainer and attach to the lace holes, ensuring the shoe wraps tightly around your foot. The strong fabric does mean they don’t stretch too much and your foot feels quite locked in. It’s not roomy, at least not in precision fit, but that tightness means it’s great for running unpredictable ground. You can poke your feet into small landing spots as you run down hills or dodge between tree roots. The heel area doesn’t have a solid firm outside like you will find on many trainers. This makes it feel more snug around the rear of the foot. This is great for steep descents and equally, you can be less worried that the shoe will pop off your foot if you’re running through deep bogs or thick mud.

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I could  easily be put off with words like tightness being used in a review of a running shoe. I like to imagine my feet are nice and free with room to float around. Forget that mindset. These trainers stay comfortable precisely because they don’t slide around on your feet too much. My 20 miler last week didn’t leave a hint of blister on my foot, despite running through bogs, pebbled beaches, and streams.

DSC_0071 *NB Thanks to Stuart Edward Vessey Grant for this pic

Now let’s be clear, the Mudclaw is called ‘Mud Claw’  for a reason. Mud is where it excels. The more extreme the more the Mudclaw seems to feel at home. The 8mm rubber studs give a grip that is similar to running in spikes but with the added advantage that you can also run hard ground in them. Surprisingly, they’re reasonably comfortable for shorter sections of road.

According to Innov8 the compound of the rubber is a dual mix of soft and hard rubber. In reality I think they’re trying to say that it will be sticky and hard-wearing. Well the sticky bit I’ll vouch for and when you run paths you can actually hear the stickiness as your feel leave the pavement. It does wear the studs though, so if you’re running a lot of pavements they will eventually take their toll but if you’re using these are they’re meant to be used, and you only have a mile or so of pavement till you can get off-road, the longevity should be fine.

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My  recent race had mile stretches of road in places and the Mudclaws were comfortable. In comparison, the Innov8 x-talon 190’s are decidedly uncomfortable on anything that isn’t soft. The lower level of support means you feel the studs more. This is why I think the Mudclaws have the support levels right. You can do longer races and harder ground without beating your feet up. The mud though, is where they work best. Even hard trails and I’d be looking for a different shoe as I’d be wearing these precisely for the grip and confidence they can provide when trails become muddy and slippery, and not for hard summer mud or dry fields.

Descending in the wet can be a precarious business but using the Mudclaws, you can really hit steep muddy downhills at full pelt, and feel stable. I was so impressed with the grip on my last race. I could imagine people sometimes buy a trail shoe and are surprised when they find themselves slipping on mud. Poor grip on mud is due to the layout of the grip. Th0e Mudclaws have lots of space between the studs which mean the shoes are able to shed clumps of mud as you run. Below is a picture of the same ground run in a Brooks Cascadia trail shoe and the Innov8 Mudclaw. Very quickly the Cascadia with its flatter sole and denser stud pattern retains the mud. Almost immediately, the shoe then becomes heavy and slippery.

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I should also mention how impressed I was with the Mudclaw for running steep uphill. Look carefully at that sole and you’ll see a groove in the rubber at the forefoot area called metaflex. This allows the toe of the shoe to flex upwards, which is great for fast uphill running, when you need to fire off your toes. I’ve run hill reps with less flexible trainers and it’s not comfortable. You need your feet to flex naturally. The Mudclaws are great for this.

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As you’ve probably realised I was pleasantly surprised with the cushioning on the Mudclaws.  They’re not highly supportive. Bear in mind that they are built as a ‘neutral’ trainer and offer no arch support. As someone with relatively flat feet this could be an issue but I don’t land on my heels and so the lack of support for pronation is not so much an issue. For some of the steep downhills where I occasionally land on my heels, the cushioning is adequate.

To provide support on the midsole, the shoe contains a plate that aligns behind the metatarsals. If you look at the x-ray above, the metatarsals are the five long bones in the foot and if you’re landing mid foot, these literally take tonnes of impact over a few miles. The ‘meta-shank’ plate does offer some protection here and it’s really welcomed when it comes to running rocky ground where sharp stones can dig in. It also reduces the feel of the studs when running on roads but not so much that you lose a sense of the surface which you need when it comes to off-road downhills.

I bought these shoes for two reasons. The first was to run a regular trail nearby to me that gets super muddy. It’s ok in the summer but in the winter, with a bit of rain, a standard trail shoes slips everywhere. Secondly, I wanted something I could race muddy off-road runs or fell races with. A shoe that would allow me to charge downhills and not slip on the uphill. These trainers are great for this. If you’re not going to be running in mud or on slippery ground, you don’t need these. If you’re only running off-road in nice weather, you will likely find a flatter, less aggressive soled trail shoe more comfortable. If you’ve got any mud runs planned in, I highly recommend these.

  • Leighton

    Jan 11, 2018 #1 Author

    Thanks – best article I could find on the net for these mudclaws – I’m off to order a pair on-line now as sadly none of my local specialist running shops within a 20 mile radius have them in stock.


    • Scottywatkins

      Jan 12, 2018 #2 Author

      Excellent. Yes, Innov8’s don’t seem to have the same presence in shops. Hopefully the discussion on sizing has helped for an online order. Happy running!


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