Brazil's Adriana da Silva runs during the women's marathon at the Pan Am Games in Toronto, Ontario, Saturday, July 18, 2015. Adriana da Silva won the silver medal.Felipe Dana/The Associated Press
Athletes and spectators at the Pan Am Games are being told to watch for signs of overheating as temperatures soar during the second weekend of the competition.
Games officials say their medical staff has treated two athletes for heat-related illness this morning, and it's possible more have been treated by their own team staff.
Dr. Julie Alleyne, the Games' chief medical officer, says that while many athletes competing at the Games are used to training in the heat, they may not be used to the humidity.
And she says the pressure of competing could drive them to push harder than they normally would in this weather.
Alleyne says organizers have increased the size of their medical team in response to the temperature, which is expected to peak around 32 degrees with the humidex hitting the 40-degree range.
Spectators are urged to wear hats, drink lots of water and apply sunscreen frequently.