U must sleep @ least 8 hrs a night or till properly rested if u
have sleep debt. Adequate sleep is part of healthy lifestyle
(besides controling stress by being nice to others).
U r only damaging your own body if u exercise after inadequate
rest.
If u r Sinkee >35 yrs w IPPT liability, pls tell that to your
MO for FFI IPPT. He may refer u for a threadmill to exclude a heart
problem (in addition to the usual pre IPPT cholesterol,
diabetes, BP, ecg., urine, etc tests). Otherwise talk to GP,
but I still think that adequate rest (for body repair @ end of
every day) is of primary importance.