The World Health Organization is warning that current transmission patterns resemble a global outbreak that infected 500,000 people 20...

Research suggests that exercising in warm, humid conditions can provide what some call “poor man’s altitude training” — improving...

A seven-month-old receives a COVID-19 vaccine formulated for under-5-year-olds in Houston, June 22, 2022. Under Robert F. Kennedy Jr.,...

Sandy Hupp, 71, trains at Greysteel Strength and Conditioning gym, in Farmington Hills, Mich., on June 20, 2025. Greysteel, a gym outside...

A view of the city during the cyclists’ ride, in Bogota, Colombia, June 26, 2025. At an altitude of 8,500 feet, Bogota is cool...

Demonstrators stack mock coffins outside the State Department in Washington on April 17, 2025, to protest the Trump administration’s...

A morning Tai Chi class at Elizabeth Street Garden in New York, on Sunday, June 11, 2023. Decades of research have established that...

Ian Otbot, 8, does his homework in his bedroom at home in Pennsylvania on July 15, 2025, as his father, Gerry Nel Otbot, looks on. Ian...