Rode 27 miles yesterday am. (mountain bike, 1.1 slicks, on pavement) Had not ridden for nearly two weeks due to work and being off on a vacation. And just as always after a layoff, my breathing was ragged until about mile 8. Even when I ride regular have to put in a couple or three miles before my breating is regular and steady. Seems like I hit a point, like flipping on a light switch, when my breathing is good. And the longer I ride, the better it becomes. And the better my breathing is, the stronger rider I am.
I am 53. Is what I describe pretty common?
Also, notice that somewhere around mile 12 I start to feel really good. This euphoria will last long after my ride.

I don't know if I'm actually faster, but I feel fast after 30 to 40 minutes. I noticed last winter that my cold fingers stopped feeling cold after the same 30 to 40 minutes.

I never noted any ragged or smooth breathing to go with this, though. I'll have to see on the next ride.

Heart rate.

I ride on a monitor on the hard and serious rides. I have found that if I ride too hard too soon it will affect the whole ride----So---

Start of the ride and gentle till 1/2 mile in where there is a rise. Get heart rate up to 130 and then recover back to 120. Then up to 140 and recover again. Give it a couple of miles then up to 150 and it hurts a bit. Fully recover and then I can ride all day at 80 to 85 % of my max and just push it up a bit on the hills---Or even get to my max on some of them.

This takes about 10 minutes in total which is better than your 8 miles.

Without that warm up I cannot push myself and it even brings the body in aswell.

Warmups - essential, take it easy for a few miles.

When I was a kid doing other things breathing easier after a warmup was called getting your second wind. First part of anything we did was just getting warmed up and into our "second wind". Then all was well.

Back when I was a kid (in my late 50s) I had the same problem for the first 4-5 miles. Now I'm 66 and don't get warmed up until about mile 7-8.

The variations in metabolism is a weird and wonderful thing. I hike, ski and snow shoe in the mountains of New Hampshire and ride a bike in Rhode Island. No matter the activity, it takes me a good 15 to 20 minutes to thououghly warm up. Since I already know this, I always startout at a comfortable, easy pace and ramp up slowly. Some of my hiking/backpacking friends, on winter trips, in temps in the low 20s F will hike in shorts and within 10 minutes begin to unzip outer layers. I have actually seen a hiker in temps in the high teens drenched in sweat with no shirt. There is simply a vast spectrum of people with huge physical abilities and requirements.

On the cycling front, I also warm up very slowly but I did read about a pro cyclist preparing for a time trial warming up for 20 minutes. I seem to remember it was Chris Horner somewhere or other.

I go with my instincts about what feels right or healthy. If you warm up slowly, that is OK - go with that.

If I start off riding hard, it takes me 6 to 7 miles to warm up and get my breathing back down to normal. Starting off at a moderate pace (13 to 15 mph) for two to three miles seems to warm me up faster and eliminates the heavy breathing.

If you've watched pro cycling on TV you've most likely hear, "He can't seem to find his rhythm", or :now he's found his rhythm". Maybe that's all it is.... needing to find your rhythm.

If you've watched pro cycling on TV you've most likely heard, "He can't seem to find his rhythm", or :now he's found his rhythm". Maybe that's all it is.... needing to find your rhythm.

It often takes me about 5-7mi to get my body in tune with the bike and the road. On a favorite "TT" ride there is a rather good sized hill (a mile to the top) about 3mi in. And the breathing is up a little but I've not really noticed what you are calling ragged. Though one hill last week put me into MHR and hard breathing.

Yup, warm-ups are good. Sometimes it takes a little longer.

The pros also warm up before a time trial. I think it is to get the acid out of their muscles. It takes me 1/2 mile easy, 1 mile about 70% then I can go & go & go.

Yep. That says it all.

Warm up slow and steady. Let the magic do its thing and you've bought hours of strong spinning in the saddle.

Eight miles in heart zone 2 [fast walk equivalent] repays you handsomely.

...longer of course in really cold weather.