The significance of a machine's report of mild to moderate LVH may not be very much in an athlete. LVH on the ECG is a reflection of increased wall thickness of the ventricle, i.e. increased cardiac muscle bulk. This can occur in a variety of conditions, including high blood pressure, and athletes often show a degree of LVH too, as their heart is used to working hard. It can also be seen in cardiomyopathies, such as HOCM. In your case, it is most likely due to being very fit.
An echocardiogram, or ultrasound scan, of the heart will reveal all. I wouldn't sweat too much about it.
QDM