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Home » Review » MostFit Core Hammer and SYN Rings Review

In-Depth Reviews

MostFit Core Hammer and SYN Rings Review

1
Written by Coop Mitchell
1
Coop Mitchell

Cooper Mitchell (“Coop’) is the creator of Garage Gym Reviews. He’s produced more content on home gyms and training equipment than likely anyone else in the world and is recognized as the foremost expert in the space. When not writing about barbells, squat racks, and other pieces of equipment, he can be found eating tacos and reading biographies on dead people. Coop has been featured in prestigious publications such as The Art of Manliness, Starting Strength, Men’s Health, Business Insider and many others.

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Updated on June 20, 2023
Updated on June 20, 2023

We test and review fitness products based on an independent, multi-point methodology. If you use our links to purchase something, we may earn a commission. Read our disclosures

The MostFit Core Hammer is one of the most fun training tools we’ve used for some time. It’s not only fun but also effective as well. The SYN Rings are a unique idea for adding instability training into your programming. However, there are some shortcomings we address in our Suggest Improvements section.

MostFit

MostFit Core Hammer

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Product Highlights

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Pros & Cons

Bottom Line

Why Do Instability Training?

Instability forces stability. It sounds silly, but when you think about it, if something is unstable, you have to work to keep your body stable.

There are many different ways to force your body to keep stable, and they don’t always look like people doing pistol squats on yoga balls. Squatting using a barbell or even the standard dumbbell bench press forces you to keep the weight stable.

Although stability is required in nearly every lift, there are many tools that have come out over the years that force increased stability. For instance, the BandBell Earthquake Bar is a bar which utilizes bands and a whippy wooden bar to force stability in a dramatic way.

Instability training also allows for variety in your training. It’s not only a fun way to train, but it’s also effective.

MostFit Core Hammer Review

MostFit Core Hammer and SYN Rings

As the collection of equipment at GGR HQ continues to grow, so does the fun of the workouts. I can say with much surety that there are few things more fun thanbeating the living tar out of the ground with asledgehammer.

The problem is unless you’re remodeling your home, you can’t hit the ground with a sledgehammer. So, what do most people do, they grab a big tractor tire and beat that instead. Although this is effective, it’s inefficient and for many people, simply not feasible.

This is where the Core Hammer from MostFit comes in.

MostFit has essentially taken a sledgehammer handle and attached a tire to the end. A tire that is a round ball made of urethane…so not a tire at all, but close.

MostFit Core Hammer and SYN Rings

The handle provides a nice gripping surface and has been quite durable due to its fiberglass core that is then surrounded by plastic. Thanks to the fiberglass core, there is much less vibration than there would be had the handle been made of solid plastic or wood. If you’ve ever chopped wood or done any remodeling, you’ll understand the importance of a handle with low vibration.

MostFit Core Hammer and SYN Rings

On top of the handle lies a 12 lb (they also offer the hammer in 8 pounds) urethane ball. In reality, it’s a very simple piece of equipment that could have the review end here. However, you can’t just stick a big rubber ball on a plastic stick and expect it to take the abuse of people beating it into the ground.

This is one of the things I like so much about the Core Hammer–it appears simple to the user, but in order for it to remain durable, there’s a lot more going on within the big urethane ball.

First off, urethane is a great rubber to be used due to its low bounce and is one reason companies like Rogue Fitness are starting to create bumper plates out of urethane. It does not peel, crack, smell, discolor, or fade over time like so many other rubbers. It also won’t leave black marks on whatever you’re hitting against, all while having a dead-bounce.

MostFit Core Hammer and SYN Rings

In order for the handle and urethane head to form a tight bond, MostFit runs a steel pin through and then one inch past the handle diameter in both directions, over which the handle is then molded with urethane. The urethane then goes not just over the cross-pinned handle, but also through the cross-pin hole which is what creates the nearly inseparable bond between the handle and the head.

MostFit sells the Core Hammer in an 8-pound and 12-pound version which would likely make you assume that there is simply a steel core with Urethane surrounding it. However, that couldn’t be further from the truth. One reason the Core Hammer has a somewhat high price tag is due to the cost of urethane being rather high.

MostFit Core Hammer and SYN Rings

The Core Hammer’s head is solid urethane. This allows the user to beat the ever-living crap out of it without ever actually damaging it. Trust me, I’ve tried to make it break, and it is SOLID.

I put the Core Hammer through various workouts, but my favorite was to use it as a conditioning tool during intervals. 30 seconds on, 30 seconds off for 10 minutes will leave you begging for mercy.

Overall the Core Hammer is an excellent training tool for those without access to a tractor tire, or who simply want a better option.

MostFit SYN Rings Review

MostFit Core Hammer and SYN Rings

The Core Hammer from MostFit is a great idea with even better execution. The SYN Rings are a great idea that at lighter weights work extremely well but could use improvements regarding their materials and design for people lifting heavier poundage.

The SYN Rings from MostFit take the idea of hanging, bands with weight attached from the barbell to produce instability, and package them into a simple to use and professional looking product.

The goal of the SYN Rings is to slide over the barbell in the same way a collar would and hook weight plates or kettlebells using the strap and carabiner. The entire process is simple and much easier than throwing bands over the bar. They also look like a tool made for the job, while bands look like something your Uncle Bobby said he used to use in High School after a set of 500 lb quarter squats.

MostFit Core Hammer and SYN Rings

The SYN Rings feature a metal ring encased in hard plastic which then has a thick rubber band surrounding it. Attached to the rubber band is a nylon strap with two D-rings and a carabiner. You then hook the nylon strap through a weight plate or more preferably due to their size, a kettlebell, and perform whatever movement you would like.

I view the SYN Rings as well as simple bands over a barbell as an intermediate version of the Earthquake Bar from Bandbell. As I’m sure you’ve seen if you follow us on Instagram, we are big fans of using the Earthquake bar and its goal is to force you to stabilize the weight of the bar which has bands and weight attached.

MostFit Core Hammer and SYN Rings

The SYN Rings act in the same manner as the Earthquake bar, except in a much less dramatic way due to the barbell being so much more rigid than the wooden Earthquake bar.

This said, despite the SYN Rings having a great appearance as well as being a great idea for bringing a professional product to market, their weight limit is 45 lbs. Sure, you could buy three pairs and load up 315 lbs on the bar for squats, but they’re somewhat cost prohibitive to do so compared to bands (you can also use bands for other things as well.)

MostFit Core Hammer and SYN Rings

The instability caused by the SYN Rings is instantly noticeable, but not overly so. I would feel comfortable having someone with little experience squatting using the SYN Rings because although there is instability, it’s controllable.

If you’ve never trained with something like the SYN Rings, we recommend you giving them a shot. They’re priced well and the variety they add to your training is more than worth their cost.

Suggested Improvements

To be honest, we were having trouble coming up with ways to improve the Core Hammer outside of lowering the price. We don’t feel the price is overly high, but that’s the only area for improvement we found.

The SYN Rings do have some ways they could be improved. The first one is increasing their durability. The hard plastic that surrounds the metal ring does not look like it would hold up well to constant use and the band stretches pretty dramatically with anything over 25 lbs attached.

The other improvement that would make the SYN Rings an easier recommendation for us is if they allowed more weight to be used. We think they have the potential to be an excellent tool and would like to see various band thicknesses that could accommodate more weight for people like Powerlifters to benefit from their use (Westside Barbell would love something like this.)

Full Rating

MostFit Core Hammer And SYN Rings

The MostFit Core Hammer is one of the most fun training tools we’ve used for some time. It’s not only fun but also effective as well. The SYN Rings are a unique idea for adding instability training into your programming. However, there are some shortcomings we address in our Suggest Improvements section.

Product Brand: MostFit

Product Currency: $

Product Price: 310.20

Product In-Stock: InStock

Editor's Rating:
4.4

MostFit Core Hammer

Design – 4.5
Durability – 4.5
Value – 4
Effectiveness – 4.5
GET MostFit Core Hammer ($310.20)

MostFit Core Hammer And SYN Rings FAQs

What is MostFit?

Workouts with a sledgehammer that don’t require the use of a tire. Cardio, strength, core, mobility, rotational, and impact workouts are all possible. Portable, adaptable, and entertaining! It’s made of strong urethane and can resist a lot of pressure.

What is MostFit Hammer?

The MostFit Core Hammer is one of the most enjoyable workout equipment we’ve come across in a long time. It’s not just entertaining, but it’s also effective. The SYN Rings are a novel way to include instability training into your workouts.

Where to Purchase

MostFit

MostFit Core Hammer

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Product Highlights

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Pros & Cons

Bottom Line

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On This Page

Why Do Instability Training?
MostFit Core Hammer Review
MostFit SYN Rings Review
Suggested Improvements
Full Rating
MostFit Core Hammer And SYN Rings FAQs
Where to Purchase

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