TacomaSailor

I will join the Medicare crowd at the end of July and near as I can tell my lungs have decided they are of now of no use while cycling!

Medicare/Weak Lungs???

So my question is - for those who were pretty fit and serious cyclists for a considerable time prior to Medicare - did your Medicare eligibility signal your lungs to give up the fight?

I've been a serious and fairly well conditioned road and mountain bike rider for the last 50 years (well only 30+ for mountain bikes). I used to avoid flat land riding because I really enjoyed long strenuous hills. I was a pretty good climber - not Cat III fast but few of my friends could climb with me. My two advantages were my high tolerance for pain and the ability to run my heart at 170+ for extended periods.

Even two years ago I was still going uphill pretty fast and having fun breathing hard and suffering.

Now I feel like I can't begin to suck in enough air to keep up with my heart which is still perfectly happy purring along at 165 forever (tread mill stress test). I know that research show that VO Max for well conditioned athletes declines about 5% - 8% per decade beginning around 40 years of age. But my problem is that it seems like the lungs began losing a great deal of capacity sometime around 63 or so.

During the last five years I've been riding 5000+ miles a year and during the last two years more like 8000 miles a year.

I've had annual physicals with all the required blood tests and there are no apparent medical problems.

My legs are still strong - I can climb in the same gears as I always used with no sense of leg weakness. I can also sit on a climb and spin like crazy which my preferred method due to my 7 prior knee surgeries. But, even while spinning, I run out of lungs way, way sooner than I remember - even when I was in my early 60s.

Questions:

Did my signing up for Medicare cause my lungs to give up on the bicycle thing?

Does the decline in aerobic capacity continue in such dramatic fashion?

Will the decline stabilize at some point?

wmodavis

Don't know if I can address your specific concern or not but here goes.

I've been on Medicare about 1 year.
I started mountain biking in 2008 while living in the Philippines.
I have cardiovascular disease but it started long before I started mountainbiking - actually 14 years before.
I have had no noted lung problem either before or after medicare.
I have only had one heart attack since I began mountain biking. It was about 1.5 years ago. The other 5 were before.
I am 69.

You did not mention what your physicals included and only mentioned having blood tests. Neither of those give much clue and likely would not show heart or lung problems depending on how thorough they were and if any of them ocurred since the lung capacity decrease. The lung capacity decrease is quite suspicious. Wonder if it is more clogged coronary arteries rather than reduced lung capacity. Don't know but it is a symptom not to be ignored. Since you mentioned 'cardiovascular' seems you are suspecting some heart issues. Just cuz I've had 6 and still biking doesn't mean anyone else can do it.

If you have any suspicion of heart disease etc get it checked out. I'd suggest a "coronary artery calcium scan" which measures calcified plaque in the coronary arteries. Or perhaps a second choice would be a treadmill stress test especially since you are having some symptoms.

TacomaSailor

My cardiologist recently confirmed that my heart is in great shape (I did 19 minutes on a modified Bruce treadmill stress test recently) and will probably never be an issue for me. He said something to the effect of -

"quit worrying about your heart - it is in great shape and you'll surely die from some of the other dumb stuff you do but never from a heart problem"

I feel great most of the time. The problem is just that I feel like I am not getting enough oxygen when working hard.

HillRiderEast

If you were experiencing shortness of breath doing other things you normally do around the house, I would say let your doc know and he may want to do an Echocardiogram which could reveal more things such as leaky valves etc.

Dudelsack 

Consider a stress echo.

qcpmsame 

All great advise, and worth checking in to. Question, did your physicals include lung imaging of any/several types? the stress test, as I understand its results, only tells you the VO2 uptake and what cardiological data it can glean from the ECG leads. I had to take several VO2 uptake test for flight school in the late 70's and early 80's due to asthma developing while I was a Marine enlisted and wanted my record cleared. Maybe a pulmonologist would be a good specialist to consult. They did all of my lung tests, the exhaustive lab work the Navy BuMed wanted and took all kinds of in the lung and airway samples.

Nothing really earth shattering to recommend, let your physician work with you and be sure you clearly and loudly tell them what concerns you about your lungs. Best of luck and don't stop riding, please.

Bill

wmodavis

And a stress test is only valid if you are symptomatic. How many have passed the stress test with flying colors than had fatal MI while patting themselves on the back. Pres Clinton passed them multiple times then had quadruple bypass. So much for the helpfulness of inappropriate stress tests.
You intimated concern about heart disease. The CAC measures the disease not some surogate. It is the best test test available for that.

Richard Cranium

There's so little to go on - other than you think you might have a problem worth checking.

I have years of training logs that demonstrate what level of fitness i was at across several decades.

If you have never tested and recorded any of your races or workouts - then trying to determine whether you are aging normally will be impossible. If you have a specific medical issue - then the question isn't really cycling related. You might want to compare yourself to other family members your age - rather than ask cyclists about your well being.

Rowan

You may have developed exereise-induced asthma.

gregf83 

Perhaps it's your memory that's having problems rather than your lungs Have you actually slowed down on the climbs you regularly do? Do you track your times?

PatW

People talk about "lung capacity" but for most people it really is not a limitation. It can be for people with lung damage or a lung disease.

The major limitation is delivering oxygen to you muscles. The oxygen delivered is influenced by several things. The first is the stroke volume of your heart. As people train, their ventricles enlarge. That means their hearts can pump more blood per beat. People like this often have very low resting heart rates. I recently flipped out my physician because I was having an EKG and my heart rate was in the low 40s. Of course, your max heart rate is another variable but I don't think that training has much effect on this number. The next thing that is important is the concentration of hemoglobin in the blood. The more hemoglobin you have, the more oxygen your blood will carry per unit volume. That delivers more oxygen to your muscles which means more power. Training will increase this. My hemoglobin levels are decent but nothing remarkable. Of course, if one takes EPO, that will increase the hemoglobin concentrations in the blood.

The thing is that at sea level, the blood leaves the capillary beds of the lungs at something like 99+% oxygen saturation. Healthy people tend to have more lung capacity than they can use. They are actually limited by their heart's ability to pump enough blood and their bloods capacity to absorb oxygen.

But when one is working hard, one gets the feeling of panting and not being able to "catch one's breath"? So what is this? When oxygen gets to be limiting to the muscles, the muscles switch from aerobic metabilism to generate energy to anaerobic metabolism. The thing is that anaerobic metabolism generates about 6 ATP per CO2 molecule generated as opposed to 1 ATP per CO2 molecule generated (if I remember my metabolic equations properly but at anyrate the difference is very large). Having high concentrations of CO2 in the blood stimulates the brain to tell you to pant. I suppose that is so you can blow out the CO2 from your blood preventing the blood from becoming too acidic. A small shift in blood pH is a very bad thing.

So what seems to be happening to you is that your aerobic capacity has declined some causing you to shift to anaerobic respiration sooner which results in panting. I would wager that you lungs are probably fine. It could be that there is a problem with your heart. It could also be that you are just having more difficulty maintaining your level of fitness and it has declined.