The Green Bay Packers will host the San Francisco 49ers in the first round of the NFL playoffs on Sunday at 3:40 p.m. CST. At kickoff, the temperature at Lambeau Field is forecast to be one degree Fahrenheit, and the wind chill will make it feel like minus-17 degrees, according to The Weather Channel.
This frigid temperature is dangerous for the participants and spectators alike.
In addition to the usual health risks associated with playing football, sub-zero temperatures create distinct safety hazards for players: orthopedic injuries (i.e., affecting bone and muscle) and non-orthopedic conditions.
Frigid temperatures decrease the extensibility of muscles and tendons. Because of this, the tissue will have a higher-risk of being strained or torn during play. The most strained muscle among football players is the hamstring.
Additionally, players’ joints will become stiffer due to the cold. The joints will have less mobility and will have a decreased ability to absorb high forces. The joints most susceptible to injury are the smaller and most distal ones: toes, fingers, ankles and wrists. Therefore, these joints are more susceptible to being sprained than they otherwise would.
Just as joints and muscles become stiffer and harder in frigid temperatures, so does the ground. The playing surface at Lambeau Field will have much less give than it would in warmer temperatures and, therefore, will increase the forces absorbed by players who land on it. This will increase the risk of all collision-related injuries of players: bruises, fractures, concussions, etc.
As for non-orthopedic health concerns, the risk of dehydration is also increased in cold-weather games.
This is due to two primary mechanisms. Firstly, the players will release an increased amount of moisture during respiration as a compensation for the dryness of the surrounding cold air. Secondly, the athletes’ bodies will be working harder overall to maintain their heat at homeostasis and therefore will have a higher overall metabolism. This additional energy demand on the body will require a higher degree of hydration than it would in more temperate conditions.
Also, people with respiratory conditions (e.g. asthma) could have exacerbated symptoms due to breathing cold-dry air. These symptoms would likely include the acute onset of bronchospasms, which is caused by a constriction of the airway. This would cause moderate-to-severe breathing problems and could require medical treatment.
Another well-known health risk of frigid temperatures is frostbite. Frostbite is localized damage to skin due to freezing effects. The damage is caused by cold-induced decreased blood flow, also known as vasoconstriction, to the skin and the localized formation of ice crystals. The body parts most susceptible to frostbite are distal appendages, such as toes and fingers, as well as cheeks, lips, nose and ears.
However, the most serious health risk associated with prolonged exposure to frigid temperatures is hypothermia. According to the Mayo Clinic website:
Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temperature is around 98.6 F (37 C). Hypothermia occurs as your body temperature passes below 95 F (35 C).
The consumption of alcohol—a prevalent indulgence of many spectators at Packer games—also increases a person's chance of suffering from hypothermia. The dilation of superficial blood vessels caused by alcohol consumption will hasten the lowering of body temperature. If a person’s core body temperature decreases to about 90 degrees Fahrenheit, loss of consciousness would likely occur. Other severe medical conditions such as bradycardia (i.e., decreased heart rate) and the serious heart rhythm-disorder known as atrial fibrillation could occur at these lower core temperatures.
If the spectators and event organizers do not make adequate preparations for the dangerously cold temperature at the game, everyone in attendance will be at a higher risk for health complications. Nevertheless, no amount of preparations will be effective enough to neutralize all of the additional injury risks imposed on the players.
Dave Pratt, DPT is a licensed physical therapist focused on orthopedic and sports-related injuries.