This is what I use. I went to a buddy who is the Vega RHN and he said take this about 20-30 minutes before you do any cardio workout. it gives you an extra jump. It actually has worked and surprisingly it doesn't really have many negatives because its plant based. I'm no gluten-free vegetarian or anything, but this stuff it doesn't matter its incredible. It can be pricey but nowadays if the thing is cheap, it's going to have minimal effects on you.
Try it, I highly recommend it as they have an after workout one as well. You barely use any per workout too.