SCD carbs come mainly from fruit (ie. bananas are high carb), vegetables (ie. butternut squash is high carb), and honey. Nut butters and nut flours have some carbs, but mostly protein and fat. I've read about people on SCD who follow the kind of training regime you do. Try joining the yahoo group at http://health.groups.yahoo.com/group/BTVC-SCD/ and asking there. I know I've read posts from people who are marathoners, etc.
35 years old, Crohn's disease for 15 of them
Resection of ileocecal valve on 09/22/09
Current Meds: LDN, Pentasa, Effexor XR
Supplements: 3 kinds of Fish Oil, Multi-Vitamin, Vitamin D, Calcium, CoQ10, Enzymes
SCD since 12/01/08 - eating Stage 3 foods