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Record heat wave in the U.S. raises public health concerns
6m 29s
More than 100 million Americans this week were under some sort of heat advisory, and were warned to stay indoors if possible. From Texas to California, a massive heat wave has set record temperatures, raising concerns about how hot is too hot. W. Larry Kenney, a professor of physiology and kinesiology at Penn State, joins William Brangham for more on how extreme temperatures impact the body.