2. General information

It is always recommended to seek immediate medical attention, if there is any reason to suspect a brain injury. If a medically trained professional is not available, there are some sideline tools available for anyone to use: BMSJ’s Concussion Recognition Tool®s (CRT). You can download for free the English version of CRT 5 here: https://bjsm.bmj.com/content/51/11/872 and English version of Pocket CRT here: https://bjsm.bmj.com/content/47/5/267. These tools are available translated to many other languages, look them up in the web, print out and include it into your training kit.

Frequency of impacts and violent forces acting on a head is a significant factor in assessing the risk of brain injuries and diseases. Cumulative exposure to head impacts, especially subconcussive impacts, can have long-term consequences on brain health. Reducing the frequency of head impacts and implementing protective measures are important steps in mitigating these risks. Long-term monitoring of individuals who are at risk of frequent head impacts, such as athletes or individuals in high-risk professions, is essential.

In contact sports, athletes may experience multiple head impacts in close proximity during a single game or practice session. This close succession of impacts can contribute to the overall risk of brain injury.

Rule of thumb: the more frequent and closer in proximity, the bigger the chance the damage occurs.

Repeated head impacts, even those low in magnitude and in the absence of diagnosed concussions (so-called subconcussive events), may lead to subtle and cumulative brain changes, brain diseases and injuries. Such changes may include alterations in brain structure and function, and the accumulation of abnormal protein deposits like tau, which is associated with neurodegenerative diseases. Repeated head impacts may also lead to subtle cognitive changes that can affect attention, memory, and other cognitive functions, and they may not become apparent until later in life.
Rule of thumb: the higher the number of events when impacts and forces act on a head, the bigger the chance the damage occurs.

It is a measuring device for forces and impacts acting on a head while doing sports. The system consist of: a sensor, mobile application and cloud service.

In everyday use, every athlete, coach, trainer and parent can use ACT Head Impact Tracker to:

1. Track down the impacts occurring. High numerical values indicate more violent impacts.
   There is no clear consensus of a clear-cut danger limit of acceleration as expressed in g-force. In many studies, acceleration/deceleration under 40g have been considered likely not to cause permanent damage, but it can be extrapolated that the probability of permanent damage starts to increase in impacts within the range of 40-60g and higher.
2. Keep an eye on the impact history and load. When the previous impact occurred? How many and what kind of impacts has happened in last days / weeks / months / season / year / 3 years / career?
3. Track down the athlete/-s getting more impacts than their peers, address the issue and reduce the impact load for the individual athlete/-s.
4. Identify the trainings and drills with most head impacts, modify them or lower their frequency in the training plan to reduce the impact load for all the athletes.
5. Identify the positions more prone to head impacts, keep an eye on the players in those positions and modify the training plans to reduce the impact load for the athletes involved.
6. Demonstrating how hard the impacts are with objective measures can contribute to better awareness and understanding of the head impacts, increase mutual respect of players and athletes, and minimize unnecessary risk taking.
7. Demonstrating objectively that impacts are occurring may encourage the coaches, trainers and team personnel to introduce and apply suitable sideline procedures, like CRT.
8. Share with those who care and can help to reduce your impact load. Users can share their impact data with those who should know too. These can be for example coaches, trainers, parents and co-athletes.
9. Trained eye of a coach may detect poor techniques from the force and direction graphical illustrations.
10. Teams and clubs tracking the head impacts can tell the parents of junior athletes that they do everything they can to monitor their children on the pitch.

Regarding point 7. we highly recommend including to your “head impact protocol” a side line assessment tool such as BMSJ’s Concussion Recognition Tool®s (CRT). You can download the English version of CRT 5 here: https://bjsm.bmj.com/content/51/11/872 and English Pocket CRT in here: https://bjsm.bmj.com/content/47/5/267. They are also available in several other languages, go and look them up in the web.
If licensed medical professionals are unavailable on site, and you do not have an assessment tool available at hand, you can also see “In case of a sport incident” text in the App. You will find it in the App’s Menu. There is useful information for non-medical first responders to help deal with the situation in a calm and structured manner.

ACT Head Impact Tracker has three parts: head sensor, smartphone mobile App, and Cloud service. When  head sensor detects an event on a head with 10g or more, it sends information to a Cloud server via ACT Head Impact Tracker smartphone mobile App. The Cloud server processes the information, saves it, and sends the event data back to the assigned User Accounts where it can be accessed via mobile Apps or Browser Access in www.act-tracker.com. If the data transfers are available, this should take no more than few seconds.

All the athletes in sports where frequent impacts or forces act on a head occur.

Last updated: 2nd of April 2024

MOBILE DEVICES’ FUNCTIONALITY WITH ACT HEAD IMPACT TRACKER

Currently ACT Head Impact Tracker mobile App is only available for Android 10 and newer Android operating systems.

Test if your mobile device works with passive or active scanning.

1. Give ACT App permissions to use “Location”, “Specific location” and “Nearby devices” when applicable.

2. Turn on Bluetooth® wireless connection and activate connection to Wi-Fi or mobile data.

3. Turn on the head sensor. Create User Account and Profile in it. Add Sensor to the Profile.

4. If you cannot add sensor to the Profile (sensor cannot connect to the App), you must always use Active scanning to connect to the sensors. You can do this by tapping on “Menu” (3 bars on top of each other in the left upper hand corner of the screen) > Click “Start active scanning” > try adding sensor again to the profile. Active scan is on until you stop it by clicking on “Stop active scanning” .

5. In some rare occasions, we found that adding sensor to the profile was possible in passive scanning mode, but the sensors didn’t connect without active scanning after this. So ensure your mobile device’s scanning mode to use with creating another test impact after you have successfully added sensor to he profile. If also now you get the event information to the App without using Active  scanning, your mobile device works on passive scanning. If your mobile device is not connecting to the sensors automatically, you must use Active scanning always when you want to connect to the sensors, and receive information from the sensors.

PASSIVE SCANNING

Passive scanning means that App is automatically connecting to the ACT Head Impact Trackers when the sensors are trying to send information. Unfortunately the mobile device brands and models are increasingly banning the passive scanning use and currently we have found that only majority of Samsung mobile devices work with passive scanning.

Occasional problems with establishing and maintaining connection between the head sensors and mobile devices (no notification to the App regarding) were recorded:

– Samsung phones: a.) in some models Bluetooth® wireless connection was slow, even disconnected, if the mobile phone’s screen is switched off (= not lighted). The connection should be re-established and information from the sensors delivered when the screen is switched back on (=lighted) if the sensor(s) are in the reach of Bluetooth® wireless technology. b.) In all models pop-up window with list of devices for paring appears when Bluetooth® wireless technology is switched on. When this happens, just click “Continue” to close the window. No paring is needed, nor appearing nor choosing it on the list. Also in few occasions the phone just disconnected Bluetooth® wireless connection. If the listening sensors just stops, turn Bluetooth® wireless connection off and back on, this fixed the problem.

ACTIVE SCANNING

When Passive scanning is not working, you need to use active scanning to allow sensors to connect to the mobile device and ACT App.  Active Scan works like this: 

1. Click “Menu” (3 bars on the left upper hand corner) > Click “Start active scan” > Text turns to “Stop active scan” = Active scanning is on until you switch it off by clicking “Stop active scan”. 

2. When the text is “Start active scan” = Active scanning is not on. 

3. If needed, always use active scanning when you want to connect to the sensors.

We have not yet tested any mobile device running Android 10 or newer which does not work with Active scanning. But we have not tested all the brands and models available, nor all of their operating system and update versions, so we cannot guarantee that ACT Head Impact Tracker mobile App will work with every mobile phone brand and model.

iOS App is not yet available. The plan for iOS App launch is in the summer of 2024.

ACT Head Impact Tracker measures magnitude of impacts and forces acting on a head by initial and total maximum linear acceleration/deceleration (g-force) and Impact g-load in all sensor versions and types.

These are added with rotational movement measurement (maximum angular velocity, rad/s) in ACT Head Impact Tracker head sensor Pro.

Typically brain injury results from the combination of angular and linear forces. There is no clear consensus of a clear-cut danger limit as expressed in linear acceleration/deceleration (g-force), or that of angular velocity (rad/s) nor Impact g-load. However, in many studies acceleration/deceleration under 40g have been considered likely not to cause permanent damage, but it can be extrapolated that the probability of permanent damage starts to increase in impacts within the range of 40-60g and higher. This when considering individual and infrequent impacts. At the moment there is no specific universally accepted threshold of rad/s that could definitively diagnose a concussion, or permanent brain damage.

Rule of thumb applies: the bigger the magnitude, the bigger the chance damage may occur.

Regarding individual events above 10g, ACT Head Impact Tracker measures head impacts by maximum linear acceleration (g-force) and Impact g-load in all sensor versions and types, and by rotational movement (maximum angular speed, rad/s) in head sensor PRO version and in helmet sensor (will be introduced in 2024). Users’ impact history is saved to the Profile and can be accessed and revied also in the later occasions.

When an event with impact or forces acting on a head over 10g threshold occurs, the head sensor is trying to send information about it via Bluetooth® wireless connection to the mobile smartphone with ACT Head Impact Tracker App. If the mobile device and App are not at Bluetooth® wireless connection reach, the head sensor saves the impact data in it. The saved impact information can be transmitted when the sensor is at Bluetooth® wireless connection reach and multiple impact information can be transferred on one go.
Note: App also needs to have permission to use “Location” and when applicable (Android 12 and newer Android operating systems) “Nearby Devices”, or App cannot receive information from the sensors. Also note that if mobile data or Wi-Fi connection is not on, active and available for the smartphone with the App, the data cannot be transferred, and we suggest using Tracker mode in sensors and downloading the data from sensors when mobile data or Wi-Fi connection is available.

IMPORTANT NOTICE: Your ACT Head Impact Tracker application is part of system, where information flow from the head sensors to the cloud takes place. Use of mobile data on your mobile device with the application may occur at any time when ACT Head Impact Tracker head sensors are used. If you do not wish to be part of the system, turn Bluetooth off, or turn off the mobile data in your mobile device.

There is not sufficient information or scientific research to reliably, simply and safely classify individual impacts to “small-medium-hard” or “green-yellow-red” on the basis of g-force, angular speed (rad/s) or Impact g-load. In the absence of proven, reliable, scientific results and correlation ACT Head Impact Tracker is not telling you “when the impact is too hard, or when it is not”, nor will it tell you “when you have to seek medical help, or when not”. There simply is no safe way for a head impact measuring device way to do so. Not yet. That’s why more data and research is needed.

That is a question you have to ask them.

There is a set of great sideline tools available for anyone which you can download for free. They are BMSJ’s Concussion Recognition Tool®s (CRT). You can download the English version of CRT 5 here: https://bjsm.bmj.com/content/51/11/872 and English Pocket CRT here: https://bjsm.bmj.com/content/47/5/267. It is also available translated to many other languages, look them up in the web, print out and include it into your training kit! When an impact occurs, take out your CRT and run through it to get more information on the situation and what to do next, do’s and don’ts.
It is always recommended to seek immediate medical attention, if there is any reason to suspect a brain injury.