Exxentric kBox4 Pro User manual
kBox4 Manual
Version 8.7, Oct 2019
Pro, Lite & Active
kBox4 manual v 8.7
Personal injuries may occur if these precautions are not observed
Please read and understand user manual and warning labels prior to use.
Inspect the machine including the drive belt before use.
Damaged or worn parts and
warning labels must be replaced. See user manual for how to change and cut the drive
belt. Do not modify the machine or repair it with non OEM parts.
Never step off the kBox while the flywheels are moving. Make sure flywheels come to a
complete stop before you end the exercise, disconnect or step off.
The kBox can deliver a supramaximal* workload. Do not exercise at an intensity you
cannot manage.
Workout at a submaximal** intensity until you are familiar with the equipment.
Don’t let the pulley block hit the kBox, absorb the eccentric load BEFORE it hits the kBox.
If you feel dizzy or experience pain, stop exercising immediately.
Exxentric takes no responsibility for any injuries that may occur.
Keep away from moving and rotating parts.
This machine and accessories are intended for strength training only. Do not use in any
other way.
Exercising at maximum intensity may cause temporary staggering and uncontrolled
body movements due to fatigue. Exercise caution to prevent falling.
The machine might get slippery when wet. Use clean shoes and dry machine with a
cloth if it is wet. Shoes with spikes, dirt, stones can damage the rubber surface of the
kBox.
Never stop an exercise in top position.
Both feet have to be placed on the kBox during exercise if it’s not fixed to the ground.
Always place the kBox on a leveled surface.
If you have balancing problems, be sure to have support by a spotter or fixed object like
a wall.
Always make sure children and pets cannot access the machine when in use.
*) Supramaximal means higher than maximal. This means higher loads than your
muscle can produce themselves in a shortening (concentric) action.
**) submaximal means below maximal. In this case, we would recommend below 75% of
max intensity.
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kBox4 manual v 8.7
Contents
This Manual covers a description of the Kinetic Box,
or kBox, a Flywheel Exercise Device, a guide to its
use, and how to maintain it.
Always check exxentric.com/support for latest info and manuals.
Specifications Page 5
Introduction Page 6
Features Page 10
Usage Page 12
Maintenance Page 16
kMeter Page 18
kBox Accessories Page 19
Support Page 20
Warranty Page 21
Caution!
Like any exercise program, it is important that
users are capable of performing exercises on this
exercise equipment and have verified this with
their personal physician.
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kBox4 manual v 8.7
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kBox4 manual v 8.7
Specifications
Active
Lite
Pro
Footprint in cm (inches)
width
76 (30")
76 (30")
98 (38,5")
depth
51 (20")
51 (20")
63 (29")
height
21 (8.5")
21 (8.5")
23 (9")
Top surface in cm
(inches)
width
68.5 (27")
68.5 (27")
90 (35.5")
depth
43.5 (17")
43.5 (17")
55 (21.5")
area [sq.m]
0.29
0.29
0.50
weight
15 kg (33 lbs)
9.5 kg (21 lbs)
15.5 kg (34 lbs)
Materials
chassi
steel
aluminium
aluminium
flywheel
steel
steel
steel
color
bronze
brown, blue
brown, blue
Features
kMeter II built-in
optional*
yes
yes
drive belt autoretract
yes
yes
yes
quick change flywheel
yes
yes
yes
foot block option**
yes
yes
yes
no. of flywheels
mounted
1-2
1-4
1-4
inertia range kgm2
0.005 - 0.10
0.005 - 0.20
0.005 - 0.28
inertia factor (min to
max)
x20
x40
x56
angle adjuster
yes
yes
yes
Flywheel options
0.005
yes
yes
yes
0.010
yes
yes
yes
0.025
yes
yes
yes
0.050
yes
yes
yes
0.070
-
-
yes
*) Active is kMeter II ready. It can be pre-installed from factory or later by customer.
**) Pro has a larger platform and more positions for individual adjustment of the foot blocks.
Included with kBox4 Active, Lite and Pro platforms: angle adjuster, attachment kit, tool bag,
printed manual, spare drive belt, protective casing for mounted flywheels, built-in kMeter II (Lite
and Pro only).
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kBox4 manual v 8.7
Introduction
kBox4 - Top surface overview
kBox4 - Bottom overview
Color of parts might differ depending on when your kBox was bought.
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kBox4 manual v 8.7
Introduction (cont.)
What is it?
The kBox is a self-contained, compact exercise
platform for various strength movements. It is a
flywheel exercise device and uses the moment of
inertia to provide a high and variable resistance in
both the concentric and eccentric* movements of
the user.
*) concentric muscle action is when the muscle is being
shortened while an eccentric muscle action is when the muscle
is being elongated during action. In some literature, concentric
and eccentric is called positive (shortening) and negative
(lengthening) phase.
How Does It Work?
The kBox has an adjustable-length drive belt
wound around a shaft located beneath the
platform. Different combinations of flywheels are
mounted on the end of the shaft.
Using hand grips or a harness attached to the Pulley, the User
pulls to accelerate the flywheel and then resists to decelerate
the flywheel as the Belt winds in the other direction.
All kBox models has a recoil auto-retract system. A Drive Belt
Length Adjustment Button allows for quick adjustment of the Belt
length for the type strength work desired. Push the button to
release and adjust length or just push button to automatically
retract the belt. An extension belt is used for overhead work (for
example military press).
Setting Up the kBox
If training without both feet on the kBox is anticipated, the
platform must be attached to the floor or weighted down so it
cannot move. Gradually from May 2019 Flywheel Retaining Nut is
fixed to a holder under the kBox when shipped.
Floor attachment kit
The floor attachment kit consists of an
attachment plate and a cam lock belt.
This package is included with all models and can be used for
attaching the kBox to the floor. The attachment plate will need
to be fixed to the floor or a heavy wooden board. The kBox will
then be anchored to the plate by the belt. On newer kBox
models there are two additional slots in the corners for
attaching the kBox to the ground. To use the two slots you will
need to purchase a second floor attachment kit.
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kBox4 manual v 8.7
Flywheel protective casing
The flywheel protection piece has to be
assembled after unpacking the kBox.
This is highly recommended in order to protect against injury.
Remove cover plastic, bend and insert at the bottom of the
kBox and then the holes in the front of the chassi. See pictures
below.
The Flywheel
There are five different flywheels with inertia:
0.005, 0.01, 0.025, 0.050 and 0.070 kgm2.
They all fit the kBox4 Pro and all but the 0.070 kgm2 fit the kBox4
Lite and Active. You can mount up to four flywheels on the
kBox4 Lite and Pro and two flywheels on the kBox4 Active. This
will give a range of inertia between 0.005 and 0.280 for PRO
and 0.005-0.10 for Active.
Do not try to mount more than the maximum
capacity of flywheels.
Experimentation will determine which configuration is required
for your level of training. Mounting or changing flywheels is
done by releasing the Retaining Nut by pulling the knob on its
side, removing the nut, changing flywheel(s) and securing
them by pushing the Retaining Nut back on until it makes a
clicking noise.
Tip!
If the black knob is hard to pull out you can push the Flywheel
Retaining Nut in while pulling the black knob.
Foot Block
The Foot Block can be positioned straight or with
an angle and is secured by sliding the pins into the
holes in the front and the back of the kBox4 chassi.
Use the side with the lower angle for lateral movement and the
other side if you just want to maintain foot placement during
vertical work.
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kBox4 manual v 8.7
Angle Adjuster
The Angle Adjuster allows for more horizontal
actions in training (e.g. bent over row, swings).
Just capture the drive belt with the top of the Angle Adjuster and
snap it on. The location for placement is indicated with a sticker.
The QR code as well as the link below will lead you to a video
showing the Angle Adjuster in use. The Angle Adjuster is included
with every kBox4.
For an example of the Angle Adjuster in use:
https://youtu.be/D6LRVJb0ots
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kBox4 manual v 8.7
Features
Principle of the kBox
The kBox is a ‘flywheel multi-exercise device’.
Which muscle is being exercised depends on
which exercise is being performed.
The principle is that through muscle force you accelerate
and decelerate a flywheel (or flywheels). Exercises with
high intensity and high forces stimulate muscles to
increase in size and the nervous system to increase
activation of the muscles. These effects together
increase strength over time if the exercise is repeated
regularly.
Resistance
The resistance is variable and unlimited.
The flywheel has a specified inertia and there is no upper
limit to how much kinetic energy you can produce in the
flywheel motion. You can think of the flywheel as a weight
that weighs more if you put more effort into lifting it.
Resistance is variable so if you pull less, the flywheel will
resist less.
Every repetition in a maximal set is maximal instead of
only the last one which is the case with traditional
weights. This results in a higher training efficiency, earlier
onset of strength increase and also hypertrophy.
Note that:
The potentially higher exertion on the kBox
may lead to need for longer resting periods
between sessions to fully recover.
Eccentric Loading
The kBox provides for increased eccentric
workloads.
The skeletal muscles can produce higher force in the
eccentric, or negative phase. This is difficult to take
advantage of with traditional weights, which always
weigh the same.
If you accelerate the flywheel during the concentric, or
lifting phase and then decelerate in a shorter amount of
time, you will have to produce a higher eccentric force.
This will be similar to lifting weights that would normally be
too heavy unless assisted by a training partner(s) but
executing the eccentric (lengthening) phase by yourself.
Check Training Guide for more information on eccentric
overload.
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kBox4 manual v 8.7
Mobility
The kBox is mobile in comparison to
traditional weights.
Squatting with the kBox is equivalent to traditional
squats which would require a barbell, weights up to or
beyond 500 lbs for a strong lifter which is practically
impossible to carry around. In addition, you don’t need
rubber mats or racks to use the kBox. Further on, you do
not need spotters to be able to do 1 RM (maximal
repetition). All this is possible with the kBox which weighs
about 22 kg (48 lbs) with one flywheel included and it
can be carried and transported easily in an ordinary car.
The kBox Lite can even be checked in as luggage when
flying.
Ergonomics
Pressure on the shoulders and upper back is
one limiting factor for many when
performing traditional barbell squats.
Serious bruising can be seen after heavy sets.
Furthermore, the lumbar spine discs are under a lot of
pressure, even if the athlete has good technique. With
tall people, people with a weak core, or back problems,
squatting is almost impossible or accompanied with a lot
of discomfort or pain. With the kBox, you are able to work
out maximally or closer to maximum intensity since the
harness distributes the pressure over the shoulders and
reduces the pressure and torque on the lumbar spine.
Work Environment
The kBox is quieter when training. The area
does not have to be equipped with sound
reducing materials.
There is a much lower risk of collision so that more people
can work out in a smaller room without the risk of
interfering with each other and inducing injuries.
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kBox4 manual v 8.7
Usage
Whenever you use the kBox, make sure to absorb all the
energy in the downward phase and come to a complete
stop before the Pulley Block hits the kBox since this will
cause damage to the device!
Foot placement
Feet are placed differently depending on
which exercise you are performing.
Make sure the drive belt goes smooth into the device and
reposition yourself if it goes against the edges or twists. Use
the Foot Block for restricting your stance, lateral push
movements or heel support during calf press. Weight down
the kBox or use attachment plate if you are not standing on
the unit with both feet.
Using the harness
Attach the Harness to the Pulley with the
Harness ends turned inwards (red
double-stitched sides towards each other)
which gives a smoother contact with the thigh.
Make sure snap shackle is properly closed before you start
training. The pin in the release function must go through the
hole in the clasp completely, see marking in above photo.
The snap shackle makes it possible to have an emergency
release, just attach a cord in the snap shackle pin for the
athlete or trainer to hold and pull to release.
Be sure the Harness fits well and is not too loose (various
sizes are available). It should not slip down over the
shoulders. Upper chest strap can be loose but the bottom
strap has to be more tight for best use.
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kBox4 manual v 8.7
Using the harness (cont.)
Use the Drive Belt Length Adjustment Button to
set the Belt length to allow the Belt to fully
reach the upper end of the exercise
movement.
For beginners and rehab patients doing lower body
exercises, the top position should be just before all active
joints are fully extended. For experienced users, there can
be some slack in the top position to minimize strain on the
belt and hook at the reversal point. Remember not to stop
the movement in an extended position when the flywheel is
spinning as this will put strain on your joints if
hyperextended.
Bend your knees slightly and take up the slack in the Belt
using your hand to rotate the flywheel and rewind some of
the belt.
Now, accelerate the flywheel by starting the exercise at a
lower intensity. Accelerate the flywheel at every repetition.
After two to four repetitions you should have reached your
desired training intensity.
Perform your training set, usually 6-12 repetitions at desired
intensity.
Decelerate the flywheel on the way down and stop at the
bottom. Slowly return to your start position and let the
flywheel stop completely. Detach the Harness, step off the
platform and prepare yourself for the next set. Make sure
you get an adequate amount of rest between sets.
Using the Hip belt
The Hip belt can be used differently depending
on your preferences
1. Place the hip belt above your hips and tighten it. Attach
the pulley block directly to the hip belt without using the
loop. A solution for flexible “ass to grass” squatters.
2. Place the hip belt on your hips and attach yourself to the
pulley block using the loop on the hip belt. Only
recommended if doing squats above 90 degrees.
3. Place the hip belt on your hips with a looser fit but attach
the pulley block directly to the hip belt. Our most
frequently used option. Enables a spotter to hold the loop
in the back for extra safety.
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kBox4 manual v 8.7
Using the Grip/Bar
Attach the desired Grip or Bar.
Position your feet as described above.
Use the Drive Belt Length Adjustment Button to set the top
position for the actual exercise. As with the harness, for
beginners and rehab patients doing upper body exercises,
the top position should be just before all active joints are
fully extended. For experienced users, there can be some
slack in the top position to minimize strain on the belt and
hook at the reversal point. Remember not to stop the
movement in an extended position as this will put strain on
your joints.
Put the flywheel in motion to roll up the belt. Accelerate the
flywheel by starting the exercise at a lower intensity.
Accelerate the flywheel at every repetition. After two to four
repetitions, you should have reached your desired training
intensity.
Perform your training set, usually 6-12 repetitions.
Decelerate and stop the flywheel on the way down. Don’t
put down the handle or grip before the flywheel(s) has
come to a complete stop. Rest accordingly.
Selecting inertia
Inertia will dictate the speed and hence the
type of resistance training you are doing.
Low inertia will be higher in speed, lower in force and higher
power vs higher inertia. For max strength slow, controlled
movements with high force and low speed are warranted
and hence more inertia.
The flywheel workout zones can be helpful, if you want to
read more about this: https://bit.ly/2NENUNE
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kBox4 manual v 8.7
Flywheel Workout Zones
Warm-up
Low intensity and low-medium inertia
Power
Max intensity at low inertia
Technique
Medium inertia and low intensity
Strength
Medium to high intensity at medium to
high inertia.
Higher inertia
More eccentric overload
We want to stress that new
exercises and users should be
taught using MEDIUM inertia and
LOW INTENSITY.
Since this will be slow, controlled and
submaximal forces hence easier to
correct and less risk for injury or technical
error. When technique is correct increase
intensity and/or lower inertia for higher
speed and more power.
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kBox4 manual v 8.7
kBox maintenance
Drive Belt Cautions
The Drive Belt and its attachment to the axle is the
most sensitive part of the kBox. Be attentive to
wear and check regularly.
When the Belt shows signs of wear and tear, trim the end by
cutting off the damaged area or replace it with an original spare
Drive Belt.
For recommendations on how to prolong the lifespan of your
Drive Belt, please refer to our belt wear tutorial on YouTube.
Video: https://youtu.be/fPvs1h-rFew
Trimming worn Belt
If damage occurs close to the shaft it is possible to
cut off the damaged end and reattach the new
end. Procedure:
• Unwind all of the belt from the shaft (left picture).
• Use the Locking Pin Removal Tool to push the Belt through the
shaft and remove the Locking Pin.
• Cut off the damaged Belt. Harden edge with a lighter.
• Fold Belt around Locking Pin and pull the Belt and Pin into the
wider groove in the shaft.
• The Belt automatically locks into the groove when you pull it
firmly.
Video: https://youtu.be/TQ6En9pQvv4
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kBox4 manual v 8.7
kBox maintenance (cont.)
Replacing the
Drive Belt
Follow the steps below to complete the replacement:
Detach Drive Belt from shaft by pushing out the pin using the
Locking Pin Removal Tool.
1. Remove the Pulley Block and make a knot on the Drive Belt.
2. Push the Belt Adjustment Lever and pull the free end of the Belt
through the opening in the platform.
3. Flip kBox over. Take out all of the Belt from the Auto retract,
disconnect and fix the hook on the short strand to the kBox so
spring can’t retract.
4. Remove the old Belt completely. Take a new Belt and attach it to
the short strand and let it slide in gently into the Auto retract.
5. Take the free end through the hole in the chassi and the locking
mechanism and make a knot. Flip kBox back.
6. Put Belt through Pulley and Shaft. Lock it in the shaft with the pin.
Video: https://youtu.be/fkdpURmWK30
Maintenance of
screws
The kBox center parts (shaft, bearings and flanges) are subjected
to heavy and repeated forces. We recommend you inspect them
quarterly.
Video: https://youtu.be/7pkqJAuGQeM
Maintenance of shaft
Put WD40 (or similar) to the shaft within 8 weeks of receiving
your kBox and then once every 6 months. The frequency of applying
rust protection will increase if you have your kBox in a more humid
environment.
Toolkit
(found on shaft cover
underneath the kBox)
3mm hexkey
(flanges and shaft position screws)
Extra pin
(for Drive Belt)
Pin Removal Tool
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kBox4 manual v 8.7
kMeter
Overview
kMeter Module allows you to connect your smartphone
or tablet with your kBox and get training feedback.
Earlier kBox models had a sensor built-in and kMeter module was
connected through a 4-pin connector. kBox4 Pro and kBox4 Lite
devices built since May 2018 have the next generation of kMeter
module (kMeter II) built-in. kBox4 Active is prepared for kMeter II but it
is optional. It can be ordered and assembled from factory or bought
at a later time and installed by the user. Previous, wired, kMeter
Module is powered by a standard 9 V battery and the kMeter II is using
two AA batteries.
SmartCoach
kMeter module (wired) works with SmartCoach system but to connect
SmartCoach to kMeter II you need a special version of kMeter II with a
wire and this needs to be specified when you order your kBox or
kMeter II.
How it works
kMeter Module sends wireless data over Bluetooth to
the corresponding iOS or Android app.
The kMeter App uses rotational data and user-input of inertia to
calculate and present power in real-time and a set summary
containing a wide range of metrics. Users can input training data
after a completed set (exercise, comment and VAS 0-10 to be used
for pain or exertion for example). All data can be stored in an in-app
database for later view in the app or exported to Excel.
kMeter II has a sample rate of 10.000 Hz and receives 64 impulses per
revolution of the flywheel. This means it can accurately sample data
up to rotational speeds of 155 revolutions/second.
Manual
For info on how to connect and operate the kMeter module and app,
see kMeter manual. For information about the metrics and their
precision, check exxentric.com/kmeter-manual
Download App
“Exxentric kMeter” in AppStore and Google Play
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kBox4 manual v 8.7
kBox Accessories
Flywheel
(0.005, 0.010, 0.025, 0.050 and 0.070* kgm2)
*0.070 kgm² flywheel is not compatible
with the
kBox4 Lite and the kBox4 Active
kMeter II
feedback system
(if not built-in from factory)
kGrips
(two single grips)
kBar
(ultra light bar)
Foot block Short
(for Active and Lite)
Foot block Long
(for Pro)
Exxentric Ankle Cuff
(two single pieces)
Exxentric Hip Belt
(Normal, Small)
Exxentric Harness
(XXS, XS, S, M, L, XL, XXL)
Exxentric Head Harness
Extension Strap
For overhead movements
Exxentric
Accessory Rack
Exxentric Flywheel bag
Elevation Blocks
Decline Board
Rotational sling
Spare Drive Belts
Accessories included with all kBoxes:
Spare Drive Belt, Floor Attachment Kit, Flywheel Protective Casing, Angle Adjuster.
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kBox4 manual v 8.7
Support
More Information
For downloading latest manuals, self-help instructions
and tutorials.
www.exxentric.com/support
For maintenance procedures or continue reading this
manual, chapter “MAINTENANCE”.
www.exxentric.com/maintenance
Blog posts covering flywheel science, physiology and
practical applications with the kBox can be found at:
www.exxentric.com/news
For demos, getting-.started tutorials, the kMeter intro
course and some other information at:
www.exxentric-academy.thinkific.com
(Register with your email to use this free service).
Apps:
Exxentric kMeter
(iOS and Android)
Real-time data from the kMeter.
For more information, see kMeter chapter.
Flywheel Training
(iOS only)
Inspirational guide for new users.
Get access to tutorials, create a program and get
started!
Need assistance?
Send an email to:
Email should include:
1. Serial number
(found underneath the device)
2. Description of the encountered issue.
3. Preferably attach an image/video
(for illustration purposes)
exxentric.com/support 20
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