Testing an astronaut's strength for Mars - GIF

[mklotz]

We need an Explanation on what exactly is going on here. Or at least I need an explanation.
LaVern

Gravity on Mars is about 38% of that on Earth. The apparatus on his back pulls up on him with enough force to cancel out all but 38% of Earth gravity. Thus he feels what it would be like to walk and move around on Mars. Moving the bags back and forth helps him develop coordination in this lower gravity situation.

Of course, a bag that weighed 100 lbs on Earth would only seem to weigh 38 pounds on Mars. An astronaut would tend to "overlift" in that environment unless trained. However, the training shown here does not address that aspect of the problem.