more calories. the carb thing could work, if you're just raising total calories by adding carbs on top of your normal load of food. if you did it with fat or protein in isocaloric amounts, it would also work.
i love mark, but the carb curve is the most broscience-y crap he puts out there. seriously. if you eat primally, and aren't packing away white rice with every meal, it's pretty hard to go 'high carb' per say, and your carb count is not something you should really worry about.