After completing an entire, grueling leg workout, my weight lifting partner had me put oxygen to the ultimate test.  He put 780 lbs on the incline leg press machine and told me to do 50 reps without stopping for a rest.  I took 3 long breaths from the can and began the test.  I didn't think I had any chance of doing it, but I completed ALL 50 reps of 780 lbs after working out legs for 1 1/2 hours. 

I had NO difficulties in breathing. 

I did not feel light headed or nauseous.

Muscle endurance was maximized as I crushed the muscle.

I was sore for 4 days and Loved it!

Other Comments:

I have used oxygen in other workouts and it has increased my reps by 20% in most exercises.

My conclusion:

My reputation is really important to me. I only endorse products that really work for me. Oxygen REALLY works. It has greatly increased my muscle failure threshold. That is extremely valuable for anyone wanting to build muscle and strength.