The 3-year University Study
Over a 3-year period, in cooperation with a major university in Pennsylvania, SAFR Sports investigated the effects of accumulated sub-concussive impacts in Division I college football using advanced biomechanical technology on various cognitive processes (via virtual reality), as well as blood biomarkers, and structural and functional integrity (via MRI).
Force was measured with specially-designed helmet sensors
- BodiTrak accelerometers provided through the Head Health Network – elastic fabric with pressure monitors and impact sensors (one of the first validated sensors that measured linear and rotational force)
- Sensors provide information on acceleration, location of impact, and rotational aspect of impact
- Fitted and placed inside athlete’s helmet (different sensors for different helmet styles/brands)

Hits were measured in the following categories over a two-week period
- 25G to 80G: While not considered a concussion, repetitive hits measured in this range can cause long-term health concerns.
- 80G or more Force at this level (or higher) can cause a concussion blow.
Average Hits Per Practice
Practice Type | 80G+ | 25-80G |
Scrimmage | 15 | 150 |
Full pads | 4.33 | 107.4 |
Uppers | 0.76 | 49 |
Helmets | 0.25 | 12.25 |
Force of Hits – Results by Position
Subject Number | Position | Monitored Sessions | Total 80G | Total 25G |
1 | Tight End | 27 | 0 | 17 |
2 | Offensive Line | 42 | 3 | 95 |
3 | Defensive Line | 37 | 5 | 116 |
4 | Defensive Line | 38 | 7 | 180 |
5 | Safety | 45 | 5 | 101 |
6 | Defensive Line | 47 | 11 | 148 |
7 | Offensive Line | 47 | 10 | 455 |
8 | Offensive Line | 26 | 0 | 28 |
9 | Offensive Line | 49 | 15 | 344 |
10 | Offensive Line | 30 | 5 | 221 |
11 | Running Back | 43 | 13 | 110 |
12 | Safety | 51 | 2 | 124 |
13 | Defensive End | 37 | 4 | 155 |
14 | Defensive End | 32 | 7 | 95 |
15 | Defensive Line | 2 | 2 | 9 |
16 | Defensive Line | 36 | 2 | 99 |
17 | Defensive Line | 47 | 2 | 74 |
18 | Offensive Line | 38 | 1 | 183 |
19 | Linebacker | 45 | 1 | 151 |
20 | Offensive Line | 48 | 7 | 301 |
21 | Tight End | 37 | 13 | 205 |
22 | Linebacker | 17 | 12 | 83 |
23 | Offensive Line | 39 | 2 | 315 |
Football Position is a Factor
Findings suggests offensive and defensive lineman sustain the greatest number of impacts.
While linemen impacts are at a lower magnitude than other positions, impacts are involved in short distance on almost every play.
Cumulative impacts, even at a lower magnitude, may result in long-term health concerns.
The field study tested SAFR Helmet Covers for two weeks in the same practice environment
2015 | 2015 | 2016 | 2016 | |
Subject | Without SAFR 80G+ | With SAFR 80G+ | Without SAFR 25-80Gs | With SFAR 25-80Gs |
1 | 2 | 2 | 79 | 51 |
2 | 2 | 0 | 32 | 6 |
3 | 0 | 1 | 125 | 68 |
4 | 1 | 1 | 156 | 6 |
5 | 6 | 1 | 83 | 34 |
6 | 1 | 0 | 63 | 1 |
7 | 0 | 2 | 13 | 31 |
8 | 2 | 3 | 32 | 40 |
9 | 1 | 1 | 24 | 37 |
Further research in 2017 showed significant results compared to 2015:
Total 80G | Total 25G | Avg 80G | Avg 25G | |
2015 16 Linemen without SAFR | 83 | 2818 | 5.19 | 176.13 |
2017 34 Linemen with SAFR | 123 | 4433 | 3.62 | 130.38 |
Results from Data Collected
- With ProTechs, the number of sub-concussive hits in the 25-80G category was reduced by more than half in the 14 compared dates from 2016 to 2015.
- With SAFR Helmet Covers, the number of hits in the 80G+ category was reduced.
- SAFR Helmet Covers reduced the number and intensity of lower threshold helmet impacts that offensive and defensive linemen experienced during practice.
Published research results validate SAFR Helmet Covers performance

Journal of Concussion, Effect of subconcussive impacts on functional outcomes over a single collegiate football season. Alexa Walter, Madeleine Scaramuzzo, Tim Bream, Peter Seidenberg, Scott Lynch, Semyon M Slobounov. Published December 25, 2020.
Chapter 4: The Effect of Head Acceleration Events on Functional Outcomes: A Two Football Season Comparison Study. Alexa Walter, PhD Dissertation. Published May 5, 2020.
For more information about data or studies, please contact us.