Complex sentence: This was not realistic, as it broke the sleds and wore out the men, and after one week a big pile of food and non-essential equipment was left behind, bringing the loads down to 130 kg per sled.
Split into simpler sentences: This was not realistic, as it broke the sleds and wore out the men. After one week, they sorted out and left behind a big pile of food and non-essential equipment, bringing the loads down to 130 kg per sled.