The Army first introduced a formal fitness test to the troops in 1942. Millions of men were being called up to fight in World War II, and not all of them were prepared for the rigors of combat. To get the men in fighting shape, the Army implemented a systematic physical development program as part of the Combat Basic Training course. And the Army Ground Forces Test was designed to assess whether the program was having its desired effect. The test included squat jumps, sit-ups, pull-ups, push-ups, and a 300 yard run. The emphasis was on functional fitness and giving American GI’s the strength, mobility, and endurance they would need to tackle real tasks on the battlefield.
In 1946, a Physical Training School was created at Fort Bragg with the mission of exploring how to take the goal of functional fitness farther. The training program developed at the school and the fitness test were codified in the 1946 edition of FM 21-20, the Army’s physical training manual.
Basically, Grandpa was doing Cross-Fit before it was cool.
The physical fitness standards for service members has been relaxed since then, and more emphasis is placed on technical skills. Take a look at the fitness testing done in the 1940s, and see how tired you get just reading it. Or -you may want to try and see how well you would do! Link -via Nag on the Lake