I am male and 46 y.o. I've been on this for 6 weeks and I have ga...

I am male and 46 y.o. I've been on this for 6 weeks and I have gained 6 pounds. I've been eating the same things and going to the gym like I always do. I have also noticed that I can't do the same workout intensity as before. I wear a heart rate monitor and so I can tell that it takes less effort now to get my heart rate to a higher level than before. In short, I can only do about 80-90 percent of my previous intensity. My clothes don't feel tighter but I think it must be fluid gains even though I am on Hydrochlorothiazide as well. I'm concerned I'm going to keep gaining weight. I already have weight issues to begin with and had been keeping my weight steady for 2 years after losing 35 lbs. Has anyone here found an alternative to Lisinopril that treats their bp without the weight gain issues?