About "bad backs": most complainants of this malady are suffering from muscular issues. These can be brought on from inactivity, excess activity, imbalances, sudden input arising from ballistic movement intentional or inadvertent in the course of daily function, etc. The percentage of humans that have or will suffer from back pain in their life is amazingly large.
If you suffer from back pain, please get a medical diagnosis to eliminate some serious disorders before going to the gym to "burn your abs"! Some back issues cannot be treated by exercise or even physical therapy and trying to do so can make a bad situation much, much worse.
If you need to relieve common muscular origin back pain, strengthening the "core" can be the ticket. NOTE: that does not necessarily mean lots of ab work; overworking the abdominals can cause back pain and this is especially so if you do exercises like leg lifts, str. leg sit-ups, bicycles, twisting toe touches and others of this sort.
Peeps with weak abs should strengthen them and that means heavier resistance crunches within an 8-15 repetition range. That is: resistance that becomes uncomfortably difficult between 8 and 15 reps; not impossible and certainly not "going for the burn" at reps in excess of 25 or compound sets, total volume in the 100's! High rep range and total volume is good to train muscle endurance at a low strength level; not what we want here.
Peeps with weak lumbars should train them for strength; that means back extensions done properly to move the resistance from a starting position with a flexed back (somersault position) to a finish with an arched (think Roman bridge) back.
Please note that if you have weak lumbars and you train your abs (instead of your spinal erectors) with high rep sets, you will make your back weaker and your problem much worse! As a personal trainer, I have "cured" low back pain in many individuals simply by stopping their excessive ab training and teaching them to do proper back extensions with appropriate resistance. True back extensions are not a function of deadlifts or "good mornings" by the way; these are only "isometric" exercises for the back and not as effective as extensions.
The first step in "curing" back pain is probably reducing bodyweight for many clients through graded, heart-rate monitored cardio exercise as a focus, even as they begin to learn to strengthen the core in totality.
I am 65 BTW and have been diagnosed with severe spinal stenosis (not addressable by exercise); the ZX14 is THE most comfortable bike I have ever ridden and the only one that I can ride for several hundred miles in a day. Who is "too old" to ride a ZX14? I am sure I don't know. I am also sure there are peeps with diagnosis's that would preclude riding anything, but that is not perforce a function of age.
* Last updated by: PaulAB on 2/17/2013 @ 2:14 PM *
Nothing is more responsible for the good old days than a bad memory. (Franklin Pierce Adams)