Lumbosacral spine and sacroiliac joints

Hi
I have been diagnosed with the following below. Can anyone assist with better understanding what is involved in preventing this condition from deteriorating. I love to surf and cannot go without it at least 5 times a week. I also train in a gym at least 3 times a week, love skateboarding and snowboarding. What should I do to continue my lifestyle from deteriorating??Is this serious??
An upper lumbar scoliosis convex to the right is present associated with moderate verbal rotation.
There is a quite severe narrowing of the discs at the left aspects of discs between T12 and L3 and there is a moderate narrowing of the right aspect of the 4/5 disc.
Prominent osteophytes account for density overlying the vertebral bodies adjacent to the 2/3 lumbar disc.
There is a mild modelling deformity of the T12 and L1 vertebral bodies with a few shallow old endplate irregularities, these features suggestive of past vertebral osteochondritis.
No significant verbal compression is seen.
Arthritic changes are present at the right sacroiliac joint with sclerosis and joint erosion being evident. Arthritic changes at the left side appear minimal and consist of slight sclerosis without any significant bone erosion benign evident.

Thanks Martin