There aren’t very many studies directly comparing these two forms of exercise. But there are literally hundreds of studies supporting the use of ANY physical activity or exercise for your better health. Even 10 minutes of exercise twice a day has been shown to help.
In the case of chronic low back pain, there have been a few studies looking at Pilates or yoga. Six-weeks of Pilates brought about an eight per cent improvement in function (decreased disability). That’s not really very much change. The same study had a group of chronic back pain sufferers in a 10-week program of Pilates. That group had a 48 per cent improvement. Now, that’s more like it.
On the other hand, a recent study using yoga as a treatment modality for chronic back pain sufferers found the most change took place between 12 and 24 weeks. There were benefits after only six weeks. But the improvements accumulated over time.
Given your time constraints, you may want to pursue a program of lumbar stabilization through Pilates for the first six weeks and then continue on your own for the added benefit during the work-training program. From all the studies done with these two forms of exercise, it appears that consistent and persistent follow-through in either one will bring improvements in many areas — pain reduction, decreased use of pain medications, and both decreased disability and improved function.