In a remote area of north-central Tanzania, men leave their huts on foot, armed with bows and poison-tipped arrows, to hunt for their next meal. Dinner could come in the form of a small bird, a towering giraffe or something in between. Meanwhile, women gather tubers, berries and other fruits. The Hadza live a very different kind of lifestyle — and a very active one, engaging in significantly more physical activity than what is recommended by U.S. government standards. They also have extremely low risk of cardiovascular disease.