I have been racing duathlons for the last 3 yrs and have been improving consistently.. I usallly compleete the 1st 5km run under 20 min, the 35 km bike at 34-35 avg (flat course) and get huge abdominal pain after t2 and this prevents me from compleeting adequately the last run ..24-25 min for the last 5km . I usually drink 1 bottle of water during the bike ..
any clues, any help would be greatly appreciated .. Thks