In recent years, Tabata training has become wildly popular in the fitness world. It offers a great workout in a short amount of time by integrating full-body movements and high levels of intensity. The Tabata protocol uses varying speeds and resistances in full ranges of motion and alternating short rest periods to ignite the body's metabolism and conditioning to maximize your results in a minimal amount of time. Some claims show that a 4 minute Tabata session can provide an equivalent level of conditioning to an hour-long run. It's designed to be a brutal 4 minutes if done properly, but Tabata has the potential to save a lot of time and keeps your body burning calories for hours afterwards.

There are some simple devices to assist and amplify Tabata exercises: Battle ropes, jump rope medicine balls, and resistance bands. However, one company came up with a product that provides the benefits of all of these devices in one, making it the perfect Tabata training device. It's called the Monkii 360. They also support their customers making DIY versions of their products, and have asked me to do just that for the release of the Monkii 360.

**Disclaimer**

I am not a personal trainer, exercise scientist, or in any way qualified to provide fitness advice. Please do your own research and speak to a professional before taking on a fitness regimen.

Supplies

To build your own Monkii 360 you will need a few products you can find at your local hardware and sporting goods store. My goal was to keep this build around $60 while keeping as much of the same functions and features as the original Monkii 360. I've listed all of the prices as they applied to me, your retail experience may vary, and I do encourage you to buy used or recycled materials whenever possible.

I also wanted to avoid using complex tools and techniques to make this build accessible to everyone. Also, if you've made either of my previous Monkii DIY projects, there is a good chance you have some of this stuff laying around as excess.

Materials

Nylon Webbing - Excess
1" PVC Pipe - Excess
Heat Shrink - Excess

Tools

Utility Knife
Sharpie
6" Circle template or Compass
Heat Gun
Sewing needle and thread
Dremel tool with cutting blade
Hacksaw or reciprocating saw with a PVC blade

Step 1: Video

For those that learn visually, check out this full build tutorial video. Please consider subscribing if you like the video and want to see more DIY projects like this.

Step 2: Monkii 360

Because I am trying to replicate the design of the Monkii 360, I will first outline some of its design elements and features to compare to the final DIY build

Section #1 - 360 Ball

8 Inch injection molded rubberized foam sphere
"Irradiation Grip"
- Curved hand-holds that encourage isometric tension in the forearms, biceps, and shoulders
Internal storage compartment
- Threaded cover accesses the hollow interior which stores the connection bungee and "Mass Core"
Mass Core Integration
- The hollow interior allows for adding weight to increase resistance
Three-point anchors
- Three nylon loops on the top that allow varied connection angles to the bungees
Integrated foam roller
- Rubberized foam allows for foam rolling and pressure point alleviation

Section #2 - DynaForce Bungee

The ball attaches to an anchor point with a bungee
The bungee implements a door anchor, 24" resistance band, and a carabiner attachment
All connection hardware is covered in a rubberized coating
The resistance band is covered in an elastic sheath that continues to stretch past its full extension

Step 3: DIY Plan

Here is a quick overview of the plan I came up with for this build

We will use the mini basketball as the base structure.
- The air inside the ball will be replaced with expanding foam to add rigidity to the build
We'll make the "Irradiation Grip" by gluing pieces of the foam tile around the ball
The hollow interior will be made using the PVC pipe, cleanout, and caps
The non-threaded cap will go on top and will hold the anchor straps made of nylon webbing
The bungee will be made with the resistance band with a metal ring on each end
- The resistance bands will be separated from the door anchor so we only need to make one anchor
- The knots used to tie the band to the metal ring will be secured with heat shrink
- Stronger resistance bands can be made by doubling or tripling the strands of latex tubing
The door anchor will be made using nylon webbing, 1" PVC pipe, and a carabiner
The other carabiner will connect the metal ring on the bungee to the nylon anchor on the PVC cap

Step 4: Form the Grip

Start by drawing patternsfor the larger and smaller Irradiation Grips on the foam tile. For the smaller grip I drew two circles using the outer circumference of the PVC end cap, and connected them by free-handing gentle concave curves between the circles. I repeated the process for the larger grip, but used a 6" protractor for the circles.

Cut these patterns out using a very sharp utility knife. Try to make clean cuts without lifting the blade. It helps to make a shallow cut at first then trace over it with a deeper cut.

Form the foam shapes to fitonto the basketball using the heat gun. Using the High setting on the heat gun, heat up the foam on both sides until it is pliable. Mold the foam and introduce curves along the surface so that it forms a near match to the curves of the basketball. I used the ball itself to introduce the needed shape and worked the foam from there. The foam will hold its shape when it cools.

Stick the grips to the ball using the contact cement. The type that I used requires painting the cement on both surfaces and letting it set up for a few minutes, then pressing the two surfaces together. This makes a near instant permanent bond, so try to get the placement correct. The only stipulation here is that you keep the air valve of the basketball uncovered.

Step 5: Create the Core

Cut the 3" PVC pipe down to a length of roughly 6" using a hacksaw or reciprocating saw. Clean up the cut edges with a utility blade.

Attach the PVC cleanout to the pipe using contact cement. This threaded cleanout will be the access to this core.

Cut a slot into the PVC end cap roughly 5" long in the center of the cap. I used a Dremel tool with a cutting bit. Make sure the width of the slot is wide enough to just barely allow a double strand of nylon webbing through with some effort.

Thread three nylon straps roughly 6" long each through this slot and sew their ends shut so they cannot be pulled back through. I used a thick needle and strong fishing line to sew. These will be the anchor points.

Attach the PVC end cap to the PVC pipe using contact cement or PVC cement if you have it.

Step 6: Assemble the Parts

Okay, here's the tricky part. The goal here is to cut circular holes in the top and bottom of the ball, insert the core, then inject foam to fill up the entire ball and expand to hold the core tightly and expand the ball to its full size.

Draw circles onto the larger Irradiation Grip the same dimensions as the PVC end cap on top and PVC cleanout on bottom. Make sure these circles line up with the center of the ball. You can do this by measuring the distance between the lines all around the ball and making sure they're equal.

Cut these circles using the utility knife. First cut straight into the foam and remove it, then deflate the ball and cut away the exposed rubber of the ball. The ball should still hold some of its shape given that the grips will be holding up the rubber.

Cut out the air valve of the basketball using the utility knife while the interior of the ball is exposed. Widen the hole as necessary to make sure the nozzle of the expanding foam spray can will fit.

Insert the PVC core into the ball after applying contact cement to the core circumference and interior of the foam grip that was just cut (Do not let the cement tack up here, you want the core to be able to slide through and then have the glue set up). Make sure the end of the cap and the grip material are flush. Make sure you apply cement to both ends of the ball and make a good seal.

Inject expanding foam into the basketball. Make sure you follow the directions and safety precautions published on the product canister, as this stuff can get messy and potentially dangerous. Try to evenly fill up the ball with foam by moving the nozzle around inside the ball. This foam will expand quite a bit, so don't worry about getting the ball completely full right. With any luck, the foam will expand within the ball to provide a solid, even structure. Any excess foam should escape through the nozzle hole. Allow the published time to cure the foam before handling the ball again.

Step 7: Create the Bungees

While the expanding foam does its thing you can get to work on making your resistance bands and door stop.

Cut the 1" PVC pipe using the saw. You only need about a 4" length. Smooth off the sharp edges and burrs with the utility knife.

Assemble the doorstop by running a roughly 12" length of nylon webbing through the PVC pipe and sewing the ends together. Fishing line and a sewing needle will do the trick. Slide the sewn joint into the pipe to hide it and clip a carabiner to the opposite end of webbing.

Cut the latex tubing with scissors. You will need 24" lengths for a single band, 48" for a double strength band, and 72" for a triple strength. The dimension of tubing I linked makes for roughly a 15 pound band (that is, 15 pounds of pulling force to stretch the band to 3 times its original length). Given that the band is 10 feet long, you could make one 15 pound band and two 30 pound bands. Or a 45 pound band and two 15 pound bands. This all depends on your preference.

Assemble each band by first sliding a 2" piece of heat shrink onto each end of the resistance band. If you are doubling or tripling the length slide the heat shrink over the whole bundle of banding. Tie each end of the band to a metal ring, and slide the heat shrink over the knot and sheath end. Use the heat gun to shrink the heat shrink, keeping the knot secure.

Finally you can use another carabiner to clip the lower ring of the bungee to the nylon anchor of the 360 Ball, which by now has finished curing the foam.

**NOTE** The original Monkii 360 employs an elastic sheath that spans the length of the bungee. It protects the bands and adds some more resistance when fully stretched. I tried a few methods of recreating this sheath but couldn't replicate their proprietary design with any success.

Step 8: Be Wild

To use your Monkii 360

Clip any combination of your resistance bands to the door stop, and clip the other end to any anchor loop on the ball to achieve your desired hand placement.

Set up the door stop in a door (make sure the tension is pulling the door IN to the door jamb and not out) or wrap the band and door stop into a girth hitch over a pullup bar or tree limb.
- Make sure you safely test the system first. Fully extend the resistance band and watch for loosening knots, anchor loops pulling out, or tearing in the adhesion of the grips.

Make sure you have plenty of room for a full range of motion

Monkii around! Try out some wood choppers, slams, lunges, or punches with the ball. Get creative with your movement. It doesn't take much to get your blood flowing with this thing.