I may raise my heart rate to high levels exercising a couple hours a day, but my resting heart rate is in the mid-40's because of this exercise. I'm sure on average I use less beats per day than a unfit person. I'll keep doing this just for the odd looks and "Is it normally that low?" reactions I get form nurses and doctors who take my pulse and blood pressure.

And I have a heart defect and have to see a cardiologist every year or so. I met my first cardio through the bike club in Jersey my father rides with. I've talked to him about my level of activity and my concerns. He listened and then mentioned he had a set of Zipps for sale that would be great for someone still actively racing. I've been racing them for a couple of years now.

As a nurse, it really IS enough that you can walk, be physically active and take care of your daily needs. The people to worry about are those who are short of breath while trying to complete their daily regimen and who have absolutely no energy get these things done, like dressing, hygiene, feeding themselves, working, etc.

The more one exercises the stronger their heart gets. When your heart is fatigued you will feel fatigued as well. You're heart rate will be higher than usual upon waking. You're body will communicate to you that you need to rest. Just make sure you're taking in enough nutrients, water and rest and you should be fine.

If you are exercising your heart too much or really just exercising beyond exhaustion without recovery days, your body will tell you in big ways that would lead you to the ER.

Hopefully Dr. Rios can fill you in on more of the details.

Dr. Rios?

i have Afib (irregular hearbeat) and have been examined by several cardologists. i've had several stress, EKG, echocardiograms. the docs encourage me to keep up the training and racing. exercise only strengthens the heart. but it isn't uncommon for an athlete to have a slightly enlarged heart. but as you note, this in inself isn't an issue, esp for an athlete. i have never been told that exercise damages or wears out the heart muscle. keep it up is what i have been told!

From a paramedic, and human movement training background here's my quick take on the subject.

Yes heart's can wear out. The causes are varied.

Extreme exercise may exascerbate a pre-existing condition, but is unlikely to cause a problem.

Exercise, especially aerobic base increase the collateral coronary circulation in the heart which may provide better protection or reduced damage in the case of a "heart attack"

An enlarged left ventricle is common in the so-called "Athlete's heart" This is a good thing if the bigger size is caused by thicker and stronger myocardium (heart muscle). This is usually the case. However, and enlarged left ventricle can be a bad thing is some cases, this is when the chamber size of the ventricle enlarges, but the muscle doesn't thicken up and doesn't increase in strength, eventually it becomes floppy and has a reduced capactiy to pump blood. This is usually caused by things other than exercise.

If you get your heart tested, your ECG, may show you have abnormalities or murmurs. Some of these are very normal are a result of adaptions to exercise, but sometimes it is hard to tell by those who aren't well trained in cardiology.

I read awhile back that Tour de France riders have a much shorter lifespan than average folks. I've often wondered about the reasons. Some of the ex riders got fat, which could shorten one's life, but is it possible that all those years at extreme heart rates decreased the life of the heart muscles?

TdF riders are a little different. If there were a human performance continuum, then usually health runs concurrently with fitness. Pro cyclists take it to the extreme far right, where they sacrifice health for fitness. Most people assume these words are synonymous, and for 99% of people they are, this is one of the exceptions where the two definitions diverge.

I grew up woth a heart condition and had open heart surgery twice before age 3. I did great for a long time but was told not to over exert. Later in life I had a pcemaker and a defibrilator. Was told to get some exercise but not to over do it. In november of 2000 I received a heart transplant and started thinking my old heart was wearing out from a defect and general exercise. I spoke with my transplant team and told them that I wanted to do a triathlon. I wish you could have seen the stunned looks on their faces. I am currently training for my first sprint tri...I think that the only thing that will wear out your heart is if you don't exercise and don't listen to you docs. My suggestion is to get a heart rate monitor and keep good records, drink enough fluids and keep you doc in the loop if you have any unusual symtoms. Hope this helps.:cool: