I don't know if this is what you do, but I've definitely noticed that working seriously on the power lifts (squat, deadlift, overhead press, bench press) has made my joints feel better throughout the day.
Deadlifts as a recommendation for back pain is, well... controversial. Maybe if you keep the weight low and the only source of the back pain is muscle soreness. I don't doubt it works for you, but in general people with back issues should stay away from deadlifting heavy weights.
Heavy deadlifts fixed my back pain and several people I know. Sure, anecdotal evidence, but back pain isn't well understood and there's no real evidence for your position either.
all people should stay away from heavy deadlifts until they have mastered good form of course.
As an aside, GPs tend to give bad advice on all matters of sports medicine.
Another anecdotal data point: I managed to make my back pain disappear with a combination of deadlifts, squats with good form and stretching of hip flexors. It also fixed some knee issue (side effect of strengthening the legs I guess.) Having recently moved I haven't taken the time to get a gym subscription. After 2 months of sitting all day I managed to hurt my back while sleeping (yep, it's ridiculous); I couldn't bend to tie my shoelaces for one week...
So yep, I'm convinced lifting heavy stuff is good for your back (IF you use good form, of course.)
Back pain can often be caused by having weak stomach muscles and having too much of a gut. The back ends up trying to support the weight at the front which the stomach muscles are unable to support by themselves.
Source: my GP when he told me I was basically fat. :)
Many people might have back pain because of muscle weakness or just too much sitting, I don't doubt deadlifting could help them, so could many other things. But very few of the very many people with various back issues get them properly checked, and if you have any kind of damage to the actual tissues of your spine, than adding 500lbs of extra force acting on them certainly won't help and I don't think we need extra research to see that ;) I guess it also depends what "heavy" means to you - the weight used in a deadlift will always be higher than in most over exercises, but it is not uncommon for people to lift 2, 3 or 4 times their own weight.
It's not as simple as saying that damage to the tissues of the spine are the cause of back pain. for one research example of many, see:
http://www.ncbi.nlm.nih.gov/pubmed/8747239
Studies like this have shown that herniated discs and other types of damage once thought to be the cause of back pain are present in pain-free people with a high rate of incidence.
Further, it's not known what the tradeoffs are in terms of risking damage vs the benefits of increased strength.
I do think extra research is needed.
FWIW your definition of heavy and mine seem to be about the same: A weight the subject can lift with perfect form for a small number of reps, e.g. <= 5. With training, likely to be in the range of bodyweight x 2 and up.
I never claimed damage to the tissues of the spine is the sole and only cause of back pain, I only said that if you do have damage to the tissues of the spine which is not uncommon you clearly risk making it worse by putting your tissues under huge forces - it is clearly not a health beneficial thing whether it happens to cause pain at the moment or not.
It would be strange if having the strength to lift twice your bodyweight or more would somehow be necessary for a healthy back. There are safer ways of increasing strength of the weakened muscles, but first it would be good to identify whether indeed weakened muscles are the cause of one of the causes of your problem. That's all I am saying - deadlifting is not in general a safe recommendation for undiagnosed people with back issues.
Hahaha.. Yeah, I'm healthy and young. I just meant that when my back starts hurting from sitting I know it's getting weak so I need to get my ass back in the gym and strengthen it.
It does nothing, except maybe bad things, if you don't know the cause of the back issues.
They are also extremely hard to do correctly, and any mistake in form can and will injure you, either over time or due to one bad lift. I personally can't understand why they are so often recommended to beginner lifters.
Buying a book like Starting Strength by Rippetoe and starting with low weights goes a long way to getting your form good enough that you won't seriously injure yourself.
Just to add one anecdotal data point, I've done that and so far(for about 1 year) I have not had any problems. I do squat, deadlift, bench press, press, pullups, and situps. I've worked my way up to 230lbs + bar in deadlift and 200lbs + bar in squat. I experience a little muscle soreness in the back but that is all. I still need to watch what I eat and walk to burn calories since I still need to lose a little weight.
