Howdy. About 3 months ago I developed a severe case of sciatica and have been dealing with milder lower back pain ever since. I reckon some lifestyle choices I made all contributed towards the back pain:

1. I'm very overweight, 360 pounds (down from 470 though!)
2. My bed was 15 years old and severely dilapidated
3. I was biking about 150-200 miles a week at a level that was somewhat uncomfortable to me (trying to keep up with a bike club that I had joined)
4. I have never done a "core" exercise in my life
5. I never stretched, neither before nor after a ride
6. My office closed a year prior and they transitioned me into a "work from home" position, which reduced the amount of distance I walked per day from about 4-5 miles to less than 1/4 of a mile.

In the intervening months I've taken some steps to correct the flaws in my lifestyle that I've identified:

1. I bought a new bed
2. I have started walking 3-4 miles 3 times a week
3. I have been doing some stretching exercises recommended by my Primary physician

These steps have dramatically lowered the amount of back pain I experience (especially the walking), but it's not completely gone yet.

I need to work on my weight, and in order to do so I need to be able to cycle again. But before I get going again, I've decided I need to exercise my core. The only problem is, I have no idea what I'm doing. I mean, literally no idea. I've never done core exercises before, thinking they're just "too boring", but now that I'm paying for that attitude I must finally take an interest in this.

So what are the best resources you guys can recommend? Books, online tutorials, should I perhaps even go join a gym or see a personal trainer? I'm up for anything at this point.

Thanks!

I'd vote for the gym. If you're really unfit like I was when I came back to cycling, you need basic strengthening of, well, everything.
Now that I am fit and racing again I still go to the gym. I do various core exercises because I find that a stronger core helps keep my back from hurting on long rides.

At home you can do planks, crunches and there's a bazillion yoga moves that work the core. (my wife shows them to me, usually followed by my saying "yow! that's hard!").

Stretching is important too. My wife has back problems if she doesn't work on her hamstrings.

If your back is not too bad you could start riding small amounts now.

Congrats on the weight loss!

I have always tended to get back pain if I don't work at it. I've searched online and you can find lists of exercises, or videos of how to do them. I have a few books but my current fave is this one: 7 weeks to 300 sit ups. Despite the title, its got about 30 different ab/back exercises, with specific plans based on your current level. A nice variety, and I like just having to look at a list, and not have to decide which to do for the day. I've tried yoga, I never stick with it because I find it boring -- personal preference I guess, but it probably works too.

When you are obese, it can be difficult to do stretches because the excess weight interferes with proper body mechanics. When I was at my heaviest I was introduced to planks and side planks which as basic as they are, do a good job of increasing core stability and don't require a lot of flexibility. Yoga poses like broken table and the warrior poses also aid in core strengthening. There are plenty of example on You Tube or elsewhere on line.

You don't want to do sit ups. They are OK for
fit people, but very old school.

You will have a medical supply store in your area.
Find it and buy a 16 foot long piece of stretch tubing.
You don't want the thin stuff.

You don't need it to start doing this...
https://www.youtube.com/watch?v=sRA0n...feature=relmfu

But when you do, just loop the tubing on a door knob, and pull it closed so that
the know is on the other side. You can then use it for a wide variety of exercises.

Find some steps. Start high and go down a step at a time. Don't
go down more than a step a week. All you do is lean against a step
like you were going to do a pushup. You then lift each arm and leg one at
a time. When that gets easy, lift an arm and the opposite leg at the same time.

Another exercise is using elbows and feet, suspend yourself over your mattress.
Let you middle sag down, lift it up, repeat.

There are lots of exercises, try some. I have a TRX, which can be used for
core exercises.

From my experience: Don't do crunches or sit-ups. I did crunches every day, and they didn't prevent me from straining my back.

Do planks. Side, front, and back.

There are people who say crunches are great, and there are people who say that crunches will hurt your back. But "nobody doesn't like planks." Don't take a chance, do planks.

I'm overweight, too, about 190 when I probably could be 145. For my back I started doing the Mayo Clinic Back Pain Exercises:

https://www.mayoclinic.com/health/bac...0001_D&slide=5

After a month of so of that, I started their core exercises slide show:

https://www.mayoclinic.com/health/core-strength/SM00047

For the past two years I've been taking an Iyengar yoga class offerred in the local public school Community and Adult Education program, and that has been the best. Not a weight loss thing, but real good for balance, coordination, overall strength, stretching, opening up your joints, posture and relaxing all at the same time. Not aerobic, though a lot of the standing positions can have you anaerobic. Can stand on my shoulders now, but not while riding a bike!

But back pain has been at bay for about a year.

I know in weightlifting, squats and deadlifts are good at working out your core. At 360 lbs, you might even try a few squats without weights. Squat down as low as you can, until your legs are parallel to the ground, then lift your butt back up pulling with your lower back.

Here's a book I'd recommend - bought it myself and thoroughly enjoyed it:

https://www.amazon.com/The-New-Rules-...dp/1583334602/

In addition to the above comments, I thought it good to note that walking is itself a good core exercise. As you get more comfortable walking, push the pace so that you're breathing deeply and sweating. You might think about getting some supportive trail runners or similar from a knowledgeable running store. Walking is wonderful exercise. You can gradually increase until you walk an hour 6 days a week.

walking, 20 min a day at lunchtime