I am a newbie........raced 12 yrs ago and just getting into sprints with my first one back next weekend.

My problem is........I feel great during my runs, I feel great great during my swims, I feel great during my rides.  But when I try to do a BRICK, the minute I get off my bike to go to run, I immediately get a strong pain in my inner thigh.  It is so bad I cannot run at all.  It does not hurt at any othe time or activity.

Any thoughts??  Thank you!