Hi dennis jennings,
Welcome to HCM.
While doing crunches, your inter vertebral
disk might have been displaced, pressing on the nerves exiting from the vertebral column. This could give rise to tingling sensation
along your leg.
You need to consult an orthopedic surgeon or neurologist
and if necessary an MRI
Scan may be needed.
This is not due to any cardiac problem, so you do not have to worry about that.