It is very common for fitness enthusiast people to have heart rate hovering around 55 BPM.
Normal heart rate range is 60-100 BPM.
However it is very common to find heart rate around 50-55 BPM in sport personalities , fitness freak people.
However it is never associated with light headedness
Next Steps
Do a 2d echo.
Holter monitoring test
Health Tips
Do not indulge in any physical or sport activities until the above-mentioned 2 tests rule out any serious structural Heart ailment.