So I've been having some back issues over the last two years specific to biking and, more specifically, to climbing. I'll make it brief.

-Been biking for 4 years.
-Back pain began gradually last year.
-Originally attributed to long rides and prone position.
-Play other sports without any back issues at all.

Noticed just this week that it occurs only when climbing. Biked for an hour, 9/10 effort, on flat roads, Tuesday. Not even a twinge.

Just now, biked up a 2 mile hill, ~8-10% avg grade, almost immediate back pain. It's my lower back, btw.

I will say that I was diagnosed with a slightly herniated disk about 2 1/2 years ago but it's so minor, I haven't had it surgically repaired. I mean, I play soccer without any issues at all.

I know the de facto response is to visit a doctor; however, how am I to explain that I have virtually no issues at all EXCEPT when climbing hills on a bike. Unless I miraculously happen across a doctor that knows quite a bit about biking and the kinesiol behind it, I doubt it'll help. I'm just hoping someone on here has had similar issues and can advise.

I can give you my story but YMMV. 9 years ago I had a very large herniated disc that kept me out of work for the first time in my life. I missed about 8 weeks. The pain was so bad I could not get any sleep. They gave me Vicodin but all that did was make me feel loopy for about 30 minutes then gave me an upset stomach....still much pain and no sleep. My Neurologist wanted me to have surgery as he said it was the largest herniation he had seen to date but my chiropractor referred to him as a cut-happy whack job and begged me to give him more time to work with me. One night when I was not sleeping I watched that Teeter hang ups commercial and figured "why the hell not". It was only $300 and I was desperate. To shorten an already too long story I needed no surgery thanks to that inversion table and I can jog, bike, kayak, enjoy sex (sometimes with a partner if I'm lucky) and hike mountains in the Adirondacks all with no pain. I still use that inversion table every morning and do 120 crunches on it.
I'm not saying it's going to be the answer for everyone but it's worth looking into.

A little more info. I was diagnosed with a slightly herniated disc 14 years before it exploded on me. It was a minor annoyance at worst that had me see a chiropractor 2-3 times a year but did not prevent me from playing sports or working. I think you may want to look in to inverting to keep your spine decompressed.

When climbing, your position is different on the bike than when on the flats. It should be possible to adjust your riding position and/or the bike so that it doesn't hurt.

Generally speaking, you should be in a more upright position when riding uphill, though you should really change your riding position as you climb so you can rotate through different sets of muscles.

My lower back is really stiff, most likely due to a stiff psoas (look it up to see if the pain originates in that area.) Based on your other sports activities without any pain, it's quite possible that your issue could be muscular. I was experiencing lower back pain last year, also in rides with a lot of climbing. I tried the following:

1. Let your back rest for several days until it feels normal again. In the meantime, move the saddle forward - You need to experiment with it a few millimeters at a time -- small adjustments.

2. Lowered the saddle about 1 cm. Again, you need to experiment after the first ride.

3. Warm-up for 20 mins. and stop for 2-3 mins. to stretch. This is important before attempting any long climbs. Stretch again on any break opportunity and upon finishing your ride.

Tried the above first. Another thing... Pay attention to your handlebar height if you suffer from stiff lower back. In my case, I can ride with the handlebar about 1" (max.) lower than my saddle. I tried 2" and it was too much (pain!!) With the new fitting, I still can keep up with my fast buddies who have more aggressive geometries.

If your pain is diminished after the first ride, you are on the right track, so make a few more adjustments. With my new geometry, I no longer experience back pain, except some discomfort if I'm off the bike for several weeks. It takes a week of riding (3x) with stretching to eliminate any discomfort again.

Hope it works for you, too!

Lower back pain is lack of core strength. You need a strong core to push from and after hard efforts it becomes fatigued/sore. Try 90 seconds of plank pose and 60 of boat pose every morning. In the mean time when the pain occurs pedal heel down to stretch your hamstrings, this will help.

If you pedal at 60rpm with high watts on the flats, you'll probably get the same back pain. Maybe try a lower gearing if you're in the mountains a lot, and spin up them at 90rpm.

As a person that gets pinched nerves once in a while in my lower back and neck I must first ask this question.
What some call pain to me is kind of a general term.
Can you tell if its muscle pain (tightness) or ache it would be more on the sides of your back or a sharp pain center inside something you fill but cannot touch and a sharp pain?
Muscle pains you can deal with nerve type pains go get looked at is my advice.

Thanks for all the advice. I'm going to research each and every bit of advice. I will admit to probably having a weaker core than most cyclists.

I'm going to try something this weekend. I'm going to do the same climb on different days; one staying out of the saddle and one staying completely in the saddle. Perhaps that would help me pinpoint the issue even more specifically.

I have a very similar history. I couldn't sleep a wink for a solid 3 weeks; vicodin wouldn't touch it. I was about ready to cut my leg off to get away from the pain. Had an epidural shot and two hours later, it was like it never happened. A physical therpist gave me some stretches that really seem to work for me but I have to do them regularly. I still have bouts of back pain but nothing like that 3 week period. The inversion table makes sense to me and I have been looking for a good one. Develping a strong core as suggested above will really help with your cycling endurance in general. Try not to push too big a gear when climbing because that can be very taxing to the back. But again, stretching and flexibility is key.

Yes.
But a 10% hill at 90 rpm with even a 34-29 is a tough 8.5 mph. I often use my 34-29 on a 5% grade, spinning it at 90 rpm, at the same 8.5 mph.

On steep hills, low gears will help anyway, even at low rpms. I go up short 10% grades at 5-6 mph, which is about 55-60 rpm. But with my 34-29, I can mostly do them seated without putting out an extreme effort. It lets me pedal slow enough on an 8% grade with light pedal pressure that it can be a recovery zone on a steeper climb.

I did get temporary low back pain at the top of a 2 mile, 10% average climb with 18% switchbacks. That was standing and grinding up most of the way. It's the "push pedals as hard as possible to keep from falling over" where I get the back pain. (But short steep pitches don't give me any back pain)

If you are getting the pain regularly, a triple might be worth it, so you can keep doing the climbs with faster cadence and less pedal force.

And core exercises are always good anyway. One of those blow up stability balls was recommended to me, and I think it helped. But I'm just not very good at getting around to non-bike exercise.

I get back pain if I pull up on the handlebars while riding hills. Keep your touch light on the bars when you climb.