Book 4. Chapter 20
Brin couldn't help but feel like he was at a disadvantage here; he'd sort of implied that the training he would put them through was better than whatever the [Knights] regularly did, but he had no idea what that was. Worse, he also had no equipment and no prep time.
Logically, something like aerobics and isometric exercises would work well here, but that didn't feel right. [Knights] didn't need to do planks. [Knights] needed to lift weight.
His first idea was to have them haul tree trunks around, since that's something he'd done with Davi, but the trees nearby were thin and knobby. He didn't think they'd work very well for what he had in mind.
Then he remembered they were atop the foothill of a mountain. There was rock everywhere. Good rock, too. The mountains near his home in his old world had been made of lots of sandstone and shale, which tended to form long, flat plates. The rock here was course and round, more like granite, and already Brin could see several nicely spherical-shaped boulders. He could work with that.
Since he'd already promised them a ten minute break, he left them to inspect one of the rocks. It took a lot less effort to pull it out of the ground than he expected. In his past life a job like this would've taken hours, complete with lots of digging. Now, he simply pulled it up and the entire thing came free.
The stone was a little bigger than a basketball and he'd guess around a hundred and fifty pounds. He hoped it was heavy enough to challenge some of the lower-leveled men. He couldn't use something much bigger or it would be too hard to work with.
Then just to see if it would work, he put a handle on top, summoning it with glass. He let the glass coat a large section of the stone, murmuring encouragement in the Language for it to sink into all the little holes and crevasses.
When he picked it up by the handle, he was pleased to see that it managed to hold the stone up, though he sensed the strain on the handle had it near breaking. He had to pump a good deal of Mana into the glass to strengthen it enough, but when he finished he was pleased with the result. A fairly functional kettlebell.
He spotted two more stones of the appropriate size, and pulled them from the ground. He split two pieces off of his mind and instructed them to summon handles in the same way.