Andrea Abarca, (C) leads an aerobics class in Los Guidos de Desamparados July 23, 2015. More than 300 women participated in a physical health program organized by Abarca, which aims to combat obesity and sedentary behavior in poor women living in a slum. The National Nutrition Survey shows that the Costa Rican population has 62.4 percent of adult men who are obese, while among women the percentage was 77.3, according to local media. (Photo by Juan Carlos Ulate/Reuters)

A girl clings to her mother as they travel on a flooded street amid heavy rainfall in Shenzhen, Guangdong province, China, July 24, 2015. Approximately a million people have been affected by severe downpours in several Chinese provinces, causing collapsed houses, decimating crops as well as blocking highways, reported Xinhua News Agency. (Photo by Reuters/Stringer)

Members of national folklore and ethnographic groups and employees of a museum-preserve participate in the reconstruction of daily life and traditional holidays celebrated by indigenous population of the Republic of Khakassia during a demonstration for visitors outside a traditional wooden yurt near Kazanovka village, southwest of the city of Abakan, Russia, July 24, 2015. (Photo by Ilya Naymushin/Reuters)

Revelers dance and shout as they listen to music, in front of the main stage, during the 21st Woodstock Festival in Kostrzyn-upon-Odra, Poland July 31, 2015. An estimated 200,000 people attended the ongoing festival, a brainchild of Polish journalist and social campaigner Jerzy Owsiak, on Friday. Owsiak initiated the event to say thank you to those who donated money to his GOCC charity organisation that delivers medical care for children. (Photo by Kacper Pempel/Reuters)

Stefan Dobrovolny of Austria and Inigo Munoz Elorza of Spain (R) stand in front of a quad bike during a simulated Mars mission on Tyrolean glaciers in Kaunertal, Austria, August 7, 2015. The Austrian Space Forum is sending some of its researchers to practice weight-less walking in spacesuits on a glacier which resembles the terrain on Mars. (Photo by Dominic Ebenbichler/Reuters)

A new volunteer for the Ukrainian interior ministry's “Azov” battalion takes part in tests before heading to frontlines in eastern Ukraine, at the battalion's training centre in Kiev, Ukraine, August 14, 2015. (Photo by Gleb Garanich/Reuters)

Club-goers dance at “Morning Gloryville” at the Ministry of Sound in south London August 11, 2015. Morning dance parties with names like “Morning Gloryville” and "Daybreaker" are gathering steam in cities across the world, giving rise to a movement known as “conscious clubbing”. Its founders aim to create the energy and community of electronic dance parties with fruit smoothies and coffee instead of the drugs and alcohol more common after nightfall. (Photo by Toby Melville/Reuters)

Russian President Vladimir Putin (R) looks through a window of a research bathyscaphe while submerging into the waters of the Black Sea as he takes part in an expedition near Sevastopol, Crimea, August 18, 2015. (Photo by Alexei Nikolsky/Reuters/RIA Novosti/Kremlin)