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Activbody, Inc.

4435 Eastgate Mall Suite 100

San Diego, CA 92121, USA



Device User Guide

Activforce 2 provides real-time strength and range of motion measurements to quantify patient progress in applications such as physical therapy and muscle rehabilitation. Activforce 2 functions as a handheld device to provide force and angle measurement when connected to an easy-to-use mobile companion application. Download the free Activforce 2 companion application from the Apple App or Google Play store.

Activforce 2 Components

  • Activforce 2 device

  • Rounded pad

  • Arched pad

  • Arched pad foam insert

  • Silicon pad cover for arched pad

  • Hand and leg straps

  • Mobilization belt

  • Belt loop plate

  • Custom carrying case

Attaching a Pad To The Device


Turning The Device On or Off



A BLUE flashing light indicates that the Activforce 2 device is available for a Bluetooth® connection to the companion mobile application.

A GREEN flashing light indicates the Activforce 2 device is connected to the companion mobile application.

Multiple RED continuous flashing lights indicate that the battery is low and needs replacement.

A single RED flash indicates that the device has been turned off.

Using the Device with the Hand Strap


Proper Usage of the Activforce 2 Device

App Usage

Connect the Activforce 2 device to the companion application by:

  1. Holding down the power button on the device for at least 1 second, until the LED indicator light flashes blue.

  2. The mobile companion application will display a list of available devices. Tap "Connect" on the device to connect to the application. 

  3. After properly connecting to the mobile companion application, the LED indicator light will flash green periodically.

Ensure consistent results over multiple tests by using the same testing techniques and methodology.


To ensure data privacy, use the security features of the mobile device such as automatic lock screens, or sign out of the mobile companion app when not in use. 

Measuring Force

The Activforce 2 device measures accurately when force is applied in a perpendicular

direction to the large surface areas of the device or an attached pad. Application of the force should be in the center of the surface as much as possible. Direct all force into the device directly perpendicular through the device center point. Follow the instructions provided by the Activforce 2 mobile companion application for best results.

  • Do not apply force in a non-perpendicular direction to the device.

  • Do not apply force at an angle or in a direction going across the device.

  • Do not apply force on or near to the blue band of the device.

  • Do not apply a force during the three second calibration period before the application starts the force measurement.

  • Do not move or shake the device during the force measurement.

Measuring Range of Motion

The Activforce 2 device can accurately measure angular motion when used properly. While the device is calibrating, make sure that the device is being held still in the starting position. Then, move the device in a Point A to Point B motion only. Moving the device from Point A to Point B and back to Point A can increase the possibility of an inaccurate measurement. To measure angles accurately, the Activforce 2 device should be rotated on a single axis and kept within a single plane of motion.

  • Do not rotate the Activforce 2 device in multiple axes during a measurement.

  • Do not move the Activforce 2 device in multiple planes of motion during a measurement.

  • Do not rotate the device during the brief calibration period before the application starts the range of motion measurement.

Using the Hand Strap

When using the Hand Strap attachment, ensure the strap is securely fixed in position. The Hand Strap may be used to secure the device to the user for strength and range of motion tests.

Using the Arched Pad

When using the Arched Pad attachment, ensure the attachment is securely attached in the locking mechanism. Use on hard or bony body parts for strength tests.


The Arched Pad can be used with or without the adhesive foam pad and silicon cover. If the adhesive foam pad is used, make sure it is securely fastened to the Arched pad and the silicon cover is fully attached.


It is important to apply force directly into the foam pad and not at an angle. This will reduce the risk of the foam tearing off or the silicon cover slipping resulting in incorrect measurement.

Utilize the curve of the Arched Pad to place the device against the curved body parts.

Using the Rounded Pad

When using the Rounded Pad attachment, ensure it is securely attached in the locking mechanism. Use this pad for all grip measurements. Use this attachment when pushing against an immovable object.

Using the Belt Loop Plate

When using the Belt Loop Plate attachment, keep the belt positioned perpendicular through the loops to reduce strain on the belt loops.


The plate is designed to hold the belt in position during a test and it is not designed to withstand strain or force from a test. No tension should be applied on the loops for a more accurate measurement. Keep the straps parallel to the direction of applied force so the force is transmitted to the device. Ensure the belt is wrapped over the smooth side of the device and not over the attachment side of the device.


The Round Pad with the Belt Loop Plate is recommended when the device is being pressed into an inanimate object.


The Belt Loop Plate may be used to guide the belt when the device is strapped to a fixed or immobile object.

Using the Leg Strap

When using the Leg Strap attachment, ensure the strap is securely fixed in position. Use the Leg Strap to attach the device to the subject’s larger body parts for range of motion tests.

Cleaning and Disinfecting the Device

To prevent the spread of infection and diseases, the Activforce 2 device and pad should be disinfected between each use. The Activforce 2 device external surfaces, including the rounded pad, the arched pad and silicon pad cover, can be hand wiped at room temperature with a soft cloth and a cleaning solution consisting of 70% isopropyl alcohol and water. After application, the cleaning solution should be allowed to evaporate completely.


Alternatively, a cleaning solution of 1% hypochlorite and water (10,000 ppm) can be used to wipe the device, pads and silicon covers. Antibacterial hand sanitizing agents such as non-alcohol wipes or alcohol based hand gels can also be used. Any residue from these agents can be wiped away using a soft, dry clean tissue or towel.

Replacing the Battery

The Activforce 2 device comes with a standard AAA battery, which lasts between six to twelve months, depending on usage and environmental conditions.

To replace the battery, follow these steps.


Obtain a new AAA battery and a flat-head screwdriver.


Hold the Activforce 2 device and the screwdriver with the pad attachment mechanism facing upwards. The Activforce logo should NOT be visible.


Insert the tip of the screwdriver in the small opening near the power button and gently turn the screwdriver until a CLICK sound is heard and the bottom shell lid pops slightly open. This opens the first of five latches on the bottom lid.


Gently slide the screwdriver clockwise along the edge of the Activforce 2 device, keeping the tip inside the gap between the lid and the device, until it is about an inch and a half away from the original opening near the power button.

Stop sliding and gently turn the screwdriver until a CLICK sound is heard. Continue sliding the screwdriver around the edge with the tip inside the crevice, stopping every inch and a half to turn the screwdriver to pop open the latches of the bottom lid. The bottom lid can be removed when four to five of the latches are opened.

Warnings and Contraindications

The Activforce 2 device should NOT BE USED when:

  • The user has a known allergy to silicon or plastic materials.

  • The skin contacting the device or pad is damaged, irritated or otherwise not healthy.

  • The device or attached pad is visibly damaged.

  • The device is in an environment with high heat, humidity or pressure.

This information is provided for general informational purposes only and is not intended as, nor should it be considered a substitute for, professional medical advice. Do not use the information on this website for diagnosing or treating any medical or health condition. If you have or suspect you have a medical problem, promptly contact your professional healthcare provider. The information on this website is provided “as is” without any representations or warranties, express or implied.


If the Activforce 2 device does not connect with the companion application, ensure that the application has Bluetooth permissions on the mobile device. For some devices, the Activforce 2 companion application also requires Location permissions. If connectivity problems continue to occur, replace the battery or contact for further assistance.

While the Activforce 2 mobile application performs a tare calibration operation automatically before each measurement during the calibration phase, the device can also be manually tared. To tare the device, select “Calibrate Your Device” from the settings menu of the Activforce 2 mobile companion application.

To perform a hard reset of the device, remove the battery and re-insert it after 30 seconds. The battery and the removable pads are the only user serviceable items.

Other than the  battery   replacement   and   hard reset (as   described  in  this  guide),  the Activforce 2 dynamometer is designed  for service by authorized personnel only. For further information, please contact

Additional Information


The Activforce 2 device is certified to be compliant with all required safety standards and regulations, including electro-magnetic compatibility and hazardous materials, for all territories it is distributed in. This includes these standards: Safety IEC 60601-1 and EMC EN 60601-1-2.

The Activforce 2 device is not waterproof and should not be immersed in water or other liquids.


Similar to many electronic devices, the Activforce 2 device contains flammable materials and should not be exposed to flames or other excessive heat sources.

Service Life

The Activforce 2 device has a service life of at least 30,000 cycles, or force measurements.


In the European Union, the symbol below indicates that the product should not be

disposed of with other household waste. Batteries should be discarded separately, and the device should be deposited at an appropriate facility to enable recycling. Please separate these items from other types of waste and recycle them responsibly, following your local government’s disposal guidelines.


Activforce 2 Device Specifications

Activforce 2 Device Dimensions
  • Weight: (with AAA battery) 4.8 oz / 137 g

  • Length: 3.7 in / 9.5 cm

  • Width: 3.1 in / 7.8 cm

  • Height: 1.3 in / 3.3 cm

  • Volume: (approximate) 8.5 in³ / 139 cm³

Activforce 2 Device Functional Specifications
  • Force Measurement Range: 0 to 200 lb / 0 to 90 kg

  • Force Measurement Accuracy: ± (1.4 lb + 5% of the applied force)

  • Range of Motion Accuracy: ±1° for angles measured from 0° to 33°, ±3% of the measured angle when > 33°

  • System Requirement: Android 8 or higher, iOS 13 or higher

  • Connectivity: Bluetooth 4.1

  • Operating Distance: Up to 7 ft / 2 m from mobile device

  • Battery: 1 AAA battery

  • Battery Life: Approximately 6 months, may vary with usage or environmental factors

  • Operating Temperature Range: 32° to 95° F / 0° to 35° C

  • Storage Temperature Range: -13° to 122° F / -25° to 50° C

  • Operating Humidity Range: 15% to 93% relative humidity

  • Operating Pressure Range: 20.7 in Hg to 31.3 in Hg, 700 hPa to 1060 hPa

Activforce 2 Case Dimensions
  • Weight: 29.5 oz / 835 g

  • Length: 14.2 in / 36.0 cm

  • Width: 6 in / 15.2 cm

  • Height: 3.94 in / 10.0 cm

  • Volume: (approximate) 334 in³ / 5,472 cm³

Activforce 2 Accessories Dimensions
  • Hand Strap Length: 13.5 in / 34.3 cm

  • Hand Strap Width: 1.5 in / 3.8 cm

  • Leg Strap Length: 31.5 in / 80.0 cm

  • Leg Strap Width: 1.5 in / 3.8 cm

  • Immobilization Belt Length: 97.6 in / 247.9 cm

  • Immobilization Belt Width: 1.5 in / 3.81 cm

Version 220916-A

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