Have you had your thyroid checked. Your symptoms maybe just the way your metabolism runs, but they are also typical of overactive thyroid.

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GO HARD OR GO HOME

Last season I was diagnosed with Graves Disease, which is a hyeractive thyroid. One of the symptoms is the inability to recover from physical stress. I remember going out for a ride, eat myself sick, and still bonk. That was really demoralizing. A quick blood test can tell you right away if your thyroid is out of wack.

As for eating while riding, I eat like a pig. Some people can store food better then me, but in general I have to eat all the time. I start eating during the warm up. Mid ride I'll down a 1/2 peanut butter sandwich. (nuts in general are an excellent source of fat). I also eat about 2-3 powerbars or harvent bars per ride (I'm sponsored by powerbar, so I can afford this). This is good for a 4-5 hr ride for me.

The longer (in years) your body has time to adapt it's fuel system to your training, the less you'll need to eat during a ride.

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Toys-R-Us

half a powerbar/clif bar every 30-40 minutes works for me.

i only do this on 3+ hour rides though.

if you are painfully hungry or bonking after only 2 hours something is wrong. You are either going too hard/do not have a sufficiently developed aerobic base, or are not eating adequately before and after training.

i find i can eat cereal and yogurt 45-60 min before training-- just ride easy for the first 30min or risk burping some up. try to eat long-chain carbs and some protein, not simple sugars which are gone by the time you ride.

and it's best to eat as soon as possible after training to replenish your muscle glycogen fully, helping you out on the next day's workout.