I am Dr Mbong.
In some people anything that increases pressure in the abdominal cavity (such as push-ups, sports in general, couging, sneezing
, passing hard stool etc) can cause a weakness in the abdominal wall thru which some intestinal organs can slip through (a hernia
), get stuck and become painful from compression.
The hard spot may just be post-sports CRAMPED muscle which feels hard and may be painful.
Please see a physician for a thorough examination to determine the cause.
Best wishes and regards,