Lions are powerful animals that usually hunt in coordinated groups and stalk their chosen prey. However, they are not particularly known for their stamina – for instance, a lioness’ heart makes up only 0.57 percent of her body weight (a male’s is about 0.45 percent of his body weight), whereas a hyena’s heart is close to 1 percent of its body weight. Thus, although lionesses can reach speeds of 81 km/h (50 mph), they only can do so for short bursts so they have to be close to their prey before starting the attack.