Im trying to gain some weight by building muscle so I have been weight lifting 5 days a week. I also eat a small meal every 3 hours but I only eat low glycemic index foods. It seems like the more low glycemic index foods I eat, the less energy I have. Lately I have not been able to make it through 1/4 of my workout. The moment I start trying to exert energy, I get real lethargic and my eyes get heavy and headaches like I haven't slept in days. I drink plenty of water and my urine is clear so I know im not dehydrated. My friend says that because of all the low glycemic index foods and fiber that it is taking longer for my body to process and by that my body is actually drainning energy. She also said that im probably not getting enough carbs because of the fiber. I only get about 40-70grams of fiber a day. Any ideas?