Well-built muscles underlie athletic performance in birds

Muscle structure and body size predict the athletic performance of Olympic athletes, such as sprinters. The same, it appears, is true of wild seabirds that can commute hundreds of kilometres a day to find food, according to a recent paper by scientists from McGill and Colgate universities published in the Journal of Experimental Biology . The researchers studied a colony of small gulls, known as black-legged kittiwakes, that breed and nest in an abandoned radar tower on Middleton Island, Alaska. They attached GPS-accelerometers-Fitbit for birds - onto kittiwakes to track their flight performance, discovering that they sometimes travel as far as 250 km a day to find food for their offspring. By combining data from the GPS tracker with minute muscle samples from some of the birds, the researchers found that, despite beating their wings less frequently, birds with larger muscle fibres were able to fly as fast as those with smaller fibres. The team also found that birds that flew faster had a higher number of nuclei - which produce the proteins to power flight - in their muscle cells, allowing the birds to activate more muscle fibres to power their flight. Exercising to build muscle Athletes exercise to maintain muscle tone.