For the last 3-4 months I've been doing 1:15 hour of cardio before work (usually at 7AM) while doing a very clean (and measured) diet. My macros are about 60g fat, 150g protein, 30g fiber, 60g sugar, and 10-20g complex carbs. I also try to hit the gym using a Starting Strength program on M/W/F schedule. For the most part my diet is fine to maintain this level of fitness. However, I've accidentally bonked a few times and gone hypoglycemic and been very tired and lethargic. It's VERY annoying. Also, I'm running into a wall where some of my workouts are very tough going. If I'm fully charged I can do the whole thing at 150-160 bpm but if I am depleted I end up going at 130-140 bpm. Obviously, if I'm trying to lose weight, coming home after an hour burning 800 calories, only to EAT 800 calories of carbs, is self defeating. ... so that won't work. However, that's what's recommended here (which is a great article): http://www.cptips.com/recvry.htm ... To combat this to date I've added a bit of carb cycling to my diet where I'll take my rest day and eat complex carbs throughout the day so that I'm eating at a maintenance level (zero deficit). This has the added benefit of helping with leptin levels and keeping my metabolism high. ... but this still isn't enough and I'm having problems with hypoglycemia low glycogen levels while biking. ... I think my solution is to try to stay focused on using calories from fat instead of from glycogen during my rides. I think the problem is that as my physical fitness improves, I'm tempted to haul ass which increases my glycogen usage (the more you approach V02max, he more glycogen/sugar is used for fuel). This doesn't help me lose weight as I need to eat MORE carbs to replace this glycogen. So I think I just need to rebuild my glycogen so reasonable levels, then, when I do my cardio on my bike, I need to keep my heart rate around the fat burning zone (which for me is 135-140 bpm) to avoid burning glycogen and instead burn fat. Then, when I come home, I can have SOME carbs but only to replenish the LITTLE amount of glycogen that I've lost while riding. SOMETIMES I need to go higher than 140 such as when climbing a tough hill (which is usually at 165) so this will still mean I have a small amount of glycogen lost per workout but I need to keep this minimized. I think this is the ideal scenario. I would love to hear your thoughts on this...