NFL vs AFL Injury Comparison

Note: Injury data used for this report is from the 2013 season available here: AFL and NFL.

Two weeks ago, NFL star Jamaal Charles suffered a season ending knee injury. This is bad news, not just for my fantasy football team Better Call Jamaal, but also for Charles, who will miss a precious year of his professional football career. Already this season popular players like Roethlisberger, Romo, Luck, Lynch and Bryant have missed time through injury. Australian football has also had injury problems this past season with big names like Ablett, Watson and Judd all suffering serious injuries.

As a recent convert to American football I began to wonder about the difference between the heavily padded American players and the largely unprotected Australians. Does the extra protective equipment actually reduce injuries in the NFL? And is there a difference in the type of injuries athletes sustain?

Both are full contact, aggressive games, played on grass (usually real, but sometimes synthetic) that are largely isolated to their country of origin. Many of the skills and physicality involved such as catching, tackling, bumping, and running (especially weaving and dodging while running) are common to both sports. This video does a good job at illustrating the similarities between the two sports.

The video below explains the protective equipment worn in the two sports.


So does the protective gear in the NFL mean they get less injuries than the AFL?

In a word, yes. There are two main statistics that can shed some light on this area, in raw numbers the NFL has more injuries than the AFL because it’s a larger competition with more teams and more players (The AFL has 18 teams with 818 players while the NFL has 32 teams with 1696 rostered players). When standardising the injuries to a per player basis, the AFL works out at 1.19 injuries per player and the NFL at 0.79 injuries per player. So injuries were substantially more frequent in the AFL with around a 40% difference between the two. The other aspect to consider is the severity of the injuries, this can easily be assessed through how much time a player misses due to an injury. The AFL average was 3.80 games missed per injury while the NFL average was 3.99, so injuries in the NFL were slightly more severe in 2013 but not significantly so.


Is there a difference in the type of injuries sustained and what relation does this have to game style or protective equipment?


In the NFL 18.8% of injuries occur at or above the shoulders, the area where athletes wear the most protective equipment. In the AFL 11.5% of AFL injuries occur in this area, where they wear virtually no protection. A partial explanation for this could be the different style of play in the NFL where there is more head on tackling and barging than in the AFL. Another contributing factor may be the false sense of security that safety equipment can bring. The 2004 book Safety in Ice Hockey, describes a psychological phenomenon where player’s behaviour can be influenced by the presence or absence of protective equipment. The book posits that players feel greater confidence and security when wearing protective equipment which can lead to more risk taking and dangerous play. As example of this is when players lead with their head into forceful collisions, creating a greater potential for injury.


Concussions are a minor trauma to the brain resulting from direct impact to the head. They are common to both the AFL and NFL and have been the subject of much scrutiny in recent years both from the media and the sporting organisations themselves. Concussions are one of the most serious injuries facing both football codes today because of the potential for long term health effects and possible legal ramifications. Recent study findings from Department of Veterans Affairs’ brain repository in Massachusetts, USA found 76 of 79 deceased former players tested positive for chronic traumatic encephalopathy (CTE), a degenerative brain disease only diagnosed post mortem. CTE occurs as a result of repetitive head trauma and patients with the disease can suffer from mood disorders, depression, bouts of rage, confusion, memory loss and dementia.

In 2013 a proposed settlement was reached between the NFL and 4,500 former players who claimed the NFL had not warned players and hid the damages of brain injuries. Under the agreement the NFL will contribute $765 million to provide medical assistance to over 18,000 former players suffering neurological conditions such as Alzheimer’s, amyotrophic lateral sclerosis (ALS) and CTE. The money also will fund brain injury research and education programs.

The AFL has also had its problems with concussion with a number of players retiring from the game after receiving serious head knocks. North Melbourne player Leigh Adams retired at 27 years of age after being told by a neurosurgeon that any more hits to the head could cause long term damage. In an interview with Channel 7 after his retirement, Adams said he had suffered “some really bad depression signs and anger issues” as well as some minor memory loss. “I was walking into rooms and not remembering why I was in there,” Adams said.

Both sporting leagues have similar concussion protocols that identify players that may be showing signs of concussion on the field and immediately remove them from the field of play to carry out sideline testing procedures based on the standardised concussion assessment tool (SCAT2). Results from the test are compared to baseline results taken before the season, players cleared of concussion can usually return to play while players who show signs of concussion sit out the rest of the game and are placed on the injury list until medical staff clear them to play for the team again.


AFL and NFL players both get injured around 60% of the time below the waist but there is a difference to the type of injuries they sustain. Australian football is played on a bigger field and requires a lot more endurance running and regular kicking of the ball. This could explain why the AFL suffers a greater number of soft tissue injuries with hamstring strains (17.6%), calf strains (9.5%), and groin strains (6.9%) among the most common injuries.

The NFL’s biggest problem area is the knee. 22.3% of all NFL injuries affect the knee, that is almost double the amount of the second most injured area of the upper leg (11.5%). Frequent pivoting and starting and stopping combined with lateral movement puts a high demand on the knee joint and its linkages. Strains and tears of the anterior cruciate ligament (ACL) and the medial cruciate ligament (MCL) are most common and can lead to an absence of up to a year from play depending on severity.

Theories for the reason of the high incidence of knee injuries in the NFL injuries are many and varied including artificial playing surfaces, length of pre-season, or even that the focus on reducing concussions by reducing head high tackles has lead to players tackling lower and targeting the knees.


Injuries to professional athletes can have a number of negative consequences to the sport itself. Potential for litigation, reduced fan interest and/or attendance, and rising insurance costs are some of the byproducts of injuries. In recent years the AFL and NFL have made a number of rule changes to try and reduce injuries.

The AFL has tweaked high contact rules, added a rule for forceful contact below the knees, added substitute players, tightened sling tackle rules, and capped interchanges in an attempt to reduce injuries. However injury incidence and severity has remained largely unchanged in the last two decades. Comparing 2014 injury data with the rates from 1992, injury incidence (new injuries per team per season) was 36.1 in 2014 compared to 35.4 in 1992. Injury prevalence (missed games due to injury per team per season) was 146.0 in 2014 compared to 145.9 in 1992, and the severity (missed games per injury) was 4.0 in 2014, virtually the same as 1992 when it was 4.1.

In the last five years the NFL has made several rule changes aimed at reducing the number of concussions in football. A rule prohibiting players launching and leading with their heads was introduced in 2010. Other tweaks to defender formations, kick-off rules and running back drives have also been introduced. These rules seem to be having the desired effect with a 28% reduction in concussions in the last three full seasons.

Source: PBS