Even on the Moon the Apollo spacesuits were so heavy and bulky that the Apollo astronauts couldn't move quite well in them, except in the Apollo 15-17 missions where they were improved. However on Earth where they weigh about 6 times more I wonder how they could use them for training? I think I've read somewhere that they didn't use them at all on Earth. But what suits did they use as alternatives then?
From Smithsonian museum web page.
This spacesuit was worn by astronaut Alan Shepard, and was used for training purposes prior to the Apollo 14 mission in January/February 1971.
Training suits were identical to those worn during flight, and were designed to familiarize the astronaut to the weight and "feel" of the suits to be used during the mission. As with the flight suits, training suits could be pressurized and worn with relative comfort for up to 115 hours in conjunction with the liquid cooling garment.
"... that they didn't use them at all on Earth." That is wrong!
But they used simulated backpacks for training too:
Image from the book Science Training History of the Apollo Astronauts.