The ancient people were hardy, but did not know about it. Lack of civilization, benefits, tempered man. Nature, climate, an urgent need to find food on his own influenced a person. If our ancestors were not so active, they simply froze to death in caves. There would be no large settlements, no progress. It is more difficult for a modern person, because there are many temptations, and robots do half of the work for them.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.