The best thing for you to do is gather some of your mates together and start doing some small group sessions with me, however....
most lower back injuries are due to chronic inappropriate overuse patterns. In other words, your posture and the way you go about doing menial tasks. Most acute injuries result from long term, unnoticed improper movement.
Some injuries can and will occur due to sudden overload and movement under improper biomechanical positioning and, lets face it, overtaxing a system not capable of the work load. ( don't feel bad, I do this all of the time)
A couple of things about posture:
Very few people have correct neutral posture; most people gravitate toward either a Donald Duck posture or a Pink Panther
Most professionals treat lower back injuries either by strengthening the abdominal muscles or increasing the flexibility in the lower back muscles. Doctors seem to like prescribing drugs and sloth.
I think that both of these methods are wrong! How about that!
Most lower back problems are a result of a weak lower back (spinal erectors) and tight hip flexors.
So Mike, after all that blah, blah, blah, what you want to know is ‘how do I treat this man.’
POSTURE:
Good posture generally has the head, shoulders, hips and ankles in alignment.
When you’re standing or walking around you should hold your head up high, shoulder blades back and down and stomach ( tummy) slightly sucked in. Don’t hold your breath. This isn't the army.
Think of yourself as a marionette on a string. Keep the string pulled tight. Pulled upright through the center of your body.
The HIPS:
Lack of hip mobility puts a lot of stress on the lower back. So here are a series of stretches to work on.
The first flexibility drill we want to incorporate is simply sitting on a softball. Sit down one cheek on the ball and roll around on it trying to hit every sore spot. When you find a sore spot hold for a few seconds then roll some more and find the next one. Then swap cheeks.
Hip flexor stretch; the key to the hip flexor stretch is to maintain that neutral spine. I’ve never met anyone who does this stretch correctly. Everyone uses hyper-extension of the lower back to accommodate a great degree of stretch usually pinching the back and stretching the quads at best. They key to this movement is to keep the back straight and tilt the lower pelvis upwards. Point your groin towards the ceiling.
Seated glute stretch; simply sitting down. Back upright, sitting tall, one ankle across the opposite knee, the key to this one is to slowly push the knee not only down , but away from the hip.
Lying hip stretch; laying on your back, feet shoulder width apart knees bent touch the knees together. The key to this one is not to have the knees too close to your butt.
So there's some easy exercises for hip flexibility.
Next lets look at strengthening the back.
The first thing to start is the stretch and reach. Easy. Just start cleaning the walls in your house. Seriously. Reach as high as you can overhead and press against the wall and scrub away the dirt, cobwebs, matrix lines, whatever. The movements should be small and remain small. Think karate kid (the original) wax on wax off but high overhead.
Next and keeping it easy are kick backs. On your hands and knees simply kick one leg back and hold for a second or two and do 20-30 repetitions and then switch legs.
Notice the ass sitting back 
And a third exercise is stiffleg deadlifts: for this you want to stand with your legs wide apart. Bend over as far as you can, from the hips, while keeping your back straight. The key here is not thinking you have to reach the floor. Also, when you bend over, let your butt sit back. take it easy, nice and light. just use a backpack and add milk bottles as you need to.
The secret exercise for back rehabilitation:
Running; now, don’t go starting ultra-marathons, but jog a block or two, make a couple of laps around the track. The key here, maintain your posture. Your not in a hurry, but getting a half mile to a mile jogging in will help loosen your back muscles and strengthen them. It will also strengthen your stomach muscles and respiratory system.
And here’s one I like to do.
Pick up heavy stuff!. To simplify; go to a rocky beach and wander around and pick up the rocks. No hurry, no program, no sets, no reps, no pushing yourself to your limits, just pick up what you think looks like ‘fun’ to pick up.
And
Since you’re at the beach, go for a wade. Get at least chest deep and spend 20 min in the water wading around. The buoyancy of the water will take pressure off your back and the tidal activity will massage it.
One last thing; I don’t know what kind of furniture you have but I have a couch that is just a tiny bit too short, so if I lie on it, I have to draw my knees up a bit, this takes some of the extension out of my back and helps it recover. A couple of nights sleeping on the couch does wonders for my back. Not so much for my marriage, but its only a couple of nights and this helps the heart grow fonder right?
One more last thing: change what you do. Mike, I know you carry all that heavy equipment around on your back, try carrying it around on your front, or get risky and try getting your sweetheart to carry it around .(wink, nudge). You’ll either get a few more nights on the couch or she’ll really be feeling included in your life.
