In the mid-20th century, strength training was largely ignored and even viewed with suspicion, with endurance activities dominating the scientific and popular landscape. Researchers like Karpovich were already demonstrating its safety and benefits, but cultural inertia and a lack of scientific infrastructure prevented widespread adoption.

Impact: Medium. This historical context reveals how deeply ingrained beliefs about exercise can be, and how scientific evidence alone isn't always enough to shift paradigms without cultural catalysts.

In the source video, this keypoint occurs from 00:45:04 to 00:46:39.

Sources in support: Andy Galpin (Guest, Professor of Kinesiology)