Balanced exercise, progressive overload, consistency, a good diet, and enough rest are by far the most important factors in fitness. That's been the case for 10,000 years at least. Access to a barbell and bumper plates, or a bike, or protein powder makes at least an order of magnitude less difference.
Perhaps harvesting and storing honey in limited quantities as well?
George's Hebert, a French naval officer who introduced to the world the modern military obstacle course was inspired by fitness of indigenous tribes he had met in Africa.
"Their bodies were splendid, flexible, nimble, skillful, enduring, and resistant but yet they had no other tutor in gymnastics but their lives in nature."
Hebert's Grandson, David Belle, founded Parkour.