I hope you do keep lifting heavy and dont back off like the doctor says. The doctor was saying that because heavy lifting greatly increases blood pressure (for example can go as high as 400/200 apparently) and so one could hypothesis that that increases the risk of a stroke or heart attack or whatever. Statistically speaking that may even be true.
Personally I believe in quality of life over quantity of life. To me the idea of going from a big T-man to a weedy little guy simply to decrease the chances of me having a heart attack by a couple of percent (or perhaps living a year or two longer in the nursing home) just doesnt add up and I cant fathom people who think like that.
I think doctors (on the whole, Im sure there are good doctors out there) are only interested in keeping you alive and not too concerned about your quality of life. That is I think they see you as a machine that they have to keep alive and are not too concerned about your quality of life and certainly not at all concerned about how successful you are with the ladies (that you be able to maintain a physique that has all the ladies lusting after you is the least of their concerns).
There was actually a good Atomic Dog article by TC a while back on why this is probably the case (article was on why TC only has female doctors, dentists, hairdressers etc, theme was because most males in most professions are not interested in helping you be an alpha male as that makes you a competitor to them for the women).
As long as we are on the topic Ill bitch about my own potentially physique destroying experiences with doctors. About three years ago I developed an inguinal hernia. It was causing me quite a bit of pain but because the condition is not life threatening it is not covered by Medicare (the default government funded public health insurance here in Australia). I didnt have private health insurance because I had quit my job to go back to uni full time to do a PhD and was living on a scholarship.
My doctor confirmed that I had an inguinal hernia and according to him as a public patient my only option was to go on the public hospital waiting list for surgery which being elective surgery meant I could expect to wait around two to three years before I would be operated on (a long time to live in pain).
In the mean time he strongly advised me to stop all heavy lifting and basically give up body building as the abdominal pressure caused by heavy lifting would just make the hernia worse.
So then if I had gone along with my doctors advise and done what he said I would have stopped lifting for three years and gone from a well muscled physique (Im currently 5'9" at 230lb and around 17%BF) to whatever one looks like after ceasing training for three years. I would only be being operated on now three years latter (after spending the last three years in pain).
Whats more after the repair the stitches in the muscles holding the hernia together would periodically cause me pain and prevent me from ever doing heavy lifting again (thus permanently ending my body building career and eventually putting me back to my old 140lb self or perhaps turning me into an ultra fat guy). Fortunately this did not happen because I did not take my doctors advice.
Instead I searched the internet for what the best treatments for hernia were. I discovered that other body builders who had hernias got laproscopic repairs using a mesh with no stitching method and could be back training within two weeks (theoretically within two days).
I forget the name of the technique but a quick search of the internet brings up this site http://www.hernia.org/methodsafter.html which I believe refers to the method I am talking about.
I also discovered that the laproscopic mesh repair technique (for want of a better label) had less than 1% recurrence rate compared to around 15% for the classic method. The down side of the laproscopic repair technique is that it is harder to perform than the classic method and so when done by general surgeons is more likely to lead to complications and to give worse complications (but in the hands of a specialist who only does this type of surgery the risk is no greater than the classic method).
Anyway I found a doctor in Australia who also performed the laproscopic no-stitching mesh repair technique and using my credit card (cost a couple of thousand) I had the surgery (the other bonus of the laproscopic technique is that because it only required an overnight hospital stay as opposed to weeks in hospital recovering it made it affordable for me to do).
I was home the next day and back training after around three weeks. To this day my old hernia is for all intents and purposes completely gone I train as heavy as ever (actually my right shoulder currently limits me from going ultra heavy in the the bench press but thats another story) and at 38 I have more lean mass than Ive ever had.
My current girlfriend and last two girlfriends are what I would consider 9s 10s looks wise and in their mid twenties and I would put that fact down to my body builder physique. What would my life be like if I had just happily accepted my doctors advice that for me heavy lifting was permanently over and gone the classic hernia repair route (my doctor very strongly advised against the laproscopic repair method as too risky), I shudder to think where I would be now if I had taken my doctors advice.
Moral of the story is you are probably right in ignoring your doctor regarding giving up heavy lifting (as long as you don?t have some obvious major need to drop the heavy lifting and you apparently dont) keep doing it. Act like you are old and it will become a self fulfilling prophecy (just as if I had accepted my doctors advice that I could never do heavy lifting again it would also have become a self fulfilling prophecy).
Other moral of the story is to shop around for advice and get second opinions (doctors are only human and don?t know everything and in some cases if you do the research you can be better informed on a particular topic that a particular doctor is).
Good luck with your son too.