I have stage 4 emphysema. Fev1 of 19% predicted. My normal spo2 at rest averages 95-96, it drops to mid eighties with exercise. I have golfed all my life and want to continue. I recently started using oxygen at sleep and during exercise. I use an m6 tank which weighs about 7 lbs. I have tried putting the cylinder in a fanny pack and carrying it in a case and carrying it from cart to ball or green then sitting it on ground behind me. Both methods sort of work but are exhausting carrying the extra weight which leaves me breathless even though my spo2 readings stay at 92 or above. I'm thinking of trying to just use the oxygen in the cart and leave the tank there during trips to bunkers, greens etc. has anyone tried this or have any other ideas that will help me stay on the golf course?