Hypothermia is a serious medical condition that can impede performance and ultimately be deadly. It is defined by the Wilderness Medical Society as "an unintentional drop in core temperature to 35°C (95°F) or lower." Initial symptoms can include shivering, confusion, and difficulty with coordination. If untreated, hypothermia can progress to unconsciousness and cardiac arrest. Furthermore, initial symptoms can lead to trauma or drowning based on confusion, impaired movement, and impaired decision-making.

Paddle sports pose a risk of hypothermia due to heat loss from immersion in cold water (conductive heat loss) and evaporative heat loss once out of the water. Prevention of hypothermia is vital. Paddlers can help prevent hypothermia by wearing appropriate protective gear based on both water and air temperatures. If either air or water temperatures are below 20°C / 70°F, the risk of hypothermia increases, as does the need for protective gear such as splash gear, wetsuits, or drysuits.

Paddlers should dress based on the lower value of air and water temperatures. In practice, this generally means dressing for immersion, based on the current water temperature. Changes in day-to-night temperatures should be considered. It is also prudent to be prepared to care for someone who is cold.

Recommended field treatment is described in the table below. Paddlers are encouraged to obtain wilderness first aid training that teaches how to respond to hypothermia and other cold-related illnesses.