Sorry, the randomness of your not being able to excert yourself and feeling like you can’t get enough air just sounds alot like how my asthma is. I have a pretty bad case of it, so I definately know something is seriously wrong when I do have an attack, but I hear many people have more mild symptoms. It was just a thought.
Another vote for “same here”
Scylla’s training for a fifty miler IIRC, maybe he can step in and let us know if he feels like 50 every day. I’m not training for a fifty, but I’ve always considered those low days normal. And they test the mental part of excercise more than the physical.
I vote for 3 and 4. Working out 3 or 4 days per week gives you one day between workouts. That’s fine for a while, but it’s obviously not enough rest between workouts. Rest is important and I doubt you are getting enough.
1200 calories per hour is a pretty intense workout, but if it’s all you are doing then your workouts lack variety. I suggest that you mix it up, adding easy days and hard days, and give yourself enough time to rest between hard days, and reduce the hard days to no more than once per week.
The easy days could be riding for an hour, but only at a rate that burns 500-600 calories. You heart rate should be between 50-60% of maximum. For the hard days, you might want to do what you are doing now, an full hour at 70-80% of max heart rate, or you may want to add interval training.
For interval training, warm up and ride at 60-70% of your max heart rate. Using a stopwatch or clock, increase the effort to 80-90% of your max heart rate for 30 seconds (basically, this should be an effort that you really can’t sustain for much longer than the 30 seconds). After the 30 second effort is over, return to the 60-70% level of effort and ride until your heart slows done to this rate and hold this for a minute. Then do another 30 second interval. repeat until you have done 5 or so intervals and then cool down. Once you have done this for a few weeks, you can increase the interval effort to a minute, then 90 seconds, then two minutes, etc. These are hard workouts and you’ll probably need two rest days after doing it. In fact, you’ll hate doing it because it’s hard, but if you keep it up, you will see results in the ability to do longer intervals at high levels of effort, and faster recovery (that is, your heart rate will return to a lower rate much quicker after a hard interval).
So, mix up your workouts, do easy days (or no workouts) after hard days to rest, and keep the hard days to no more than once per week (maybe twice if you think you can). And on days when you get on the bike and can’t seem to get your pace to where you should be at, then get off. It’s your body’s way of telling you it needs rest.
Oh, and use a heart rate monitor. Basic wireless models (with a chest strap) are pretty cheap and are a great tool to use.