Well luckily for you my girl has high bp, so I know a little about this.
So Lisinopril is just to lower your bp. Too lower it, and keep it low. This in no way should affect your cardio.
Now metoprolol is a beta blocker.
If anything this should make your cardio even better! You should be able to go for longer than ever. Something about how your blood uses the oxygen in your blood.
(I'm not that smart ok)
But your tolerance will go up. Your blood will take in and better use the available oxygen.
Beta blockers are notorious at reducing your heart rate and systolic pressure.
Meaning you can do more work while your heart beats slower.
Now...as far as I know these 2 drugs have no affect on the other. Like taking a antibiotic and a tylenol... 1 will not affect the other. so I really don't think you have anything to worry about.
The fact that you have high blood pressure... I'm sure you know what to look for.
If you're get lightheaded dizzy.. blurred vision... talk to your doctor.
If you don't have a blood pressure monitor for your home I highly recommend it. I recommend it to anyone who is on gear, no less has bp issues. Because $20 on Amazon can save your life!
In case you don't have 1, and are interested.
Now how it will affect your pump... more blood flow and more oxygen to your muscles is only a good thing!