I'm 58, take no prescription meds or other OTC's except omega 3-6-9. I do vigorous cardio workouts 6x a week for 51 minutes (give or take depending on how I feel, that is the base line).
2-3x a week I'll do a second light to moderate cardio workout for 1/2 an hour (2 mile brisk walk, laps in the pool, something to that extent).
Took Zenerx as directed for a week. Shortly after beginning Zenerx I noticed a steady decline in my main workout. Wrote it off to a "valley" week.
But after my day off, typically my best workout of the week, it was all I could do to make it 20 minutes-less than 40% of my normal workout and I was exhausted. Stopped taking Zenerx (wasn't working anyways) and took 2 days off from working out for the first time since I can't remember when. That was just over 3 weeks ago. Workouts slowly improved, today made it 51 minutes, though one level lower than normal.
Tonight is also the first night in 3 weeks that my heartbeat feels normal and I'm not concerned about permanent damage. After stopping Zenerx within the period for advertised to get money back a note was sent to email@example.com requesting the procedure to send the unused portion to so I could get a refund. That email came back undeliverable. So I called the 800 number during the time indicated on the website.
No live pick up but voice mail promised a quick call back, so a message was left with my phone number. Never heard back.
Reason of review: Bad quality.
Monetary Loss: $64.
Preferred solution: Full refund.
I didn't like: Side effects, Did not work.