ever since I used the rowing machine at the gym, it seems like my legs feel sort of heavy and weak, too. not enough exercise?

I hardly know what to add.  I have been trying to get in shape in a haf hearted way, not knowing how to gain back the strength I have lost.

Yet I certainly know I'm not as strong as I was a couple of years ago, even..and I'm concerned that a statin I   took, at the time   is still  leaving after effects..since it really made me very weak then.

 when i was using the rowing machine at the gym, last week  I noticed that after awhile it was my thighs that were feeling it the most...

Where I work there are a stairs, and yesterday as I went to work, I took the stairs, but was almost sorry, because of the weakness in my legs, after climbing the two flights.

Any ideas or suggestions?

matrona