BALTIMORE, March 9, 2016 (Xinhua) -- U.S. Olympic swimmer Michael Phelps demonstrates strength training techniques at the headquarters of Under Amour in Baltimore, Maryland, the United States, March 8, 2016. Phelps is training hard for the 2016 Olympics in Rio de Janeiro. (Xinhua/Yin Bogu)
BALTIMORE, March 9, 2016 (Xinhua) -- U.S. Olympic swimmer Michael Phelps trains at the headquarters of Under Amour in Baltimore, Maryland, the United States, March 8, 2016. Phelps is training hard for the 2016 Olympics in Rio de Janeiro. (Xinhua/Yin Bogu)
BALTIMORE, March 9, 2016 (Xinhua) -- U.S. Olympic swimmer Michael Phelps smiles during an interview at the headquarters of Under Amour in Baltimore, Maryland, the United States, March 8, 2016. Phelps is training hard for the 2016 Olympics in Rio de Janeiro. (Xinhua/Yin Bogu)
BALTIMORE, March 9, 2016 (Xinhua) -- U.S. Olympic swimmer Michael Phelps attends a training session at the headquarters of Under Amour in Baltimore, Maryland, the United States, March 8, 2016. Phelps is training hard for the 2016 Olympics in Rio de Janeiro. (Xinhua/Yin Bogu)
