Liquid oxygen tank. Usually, oxygen is a gas. But at lower temperatures, it becomes a liquid. It takes up less space than gas, so you can store a lot more liquid oxygen in a thermos-like tank.

You can also place your hands on the treadmill bars for support. If you use an oxygen tank, secure the tube that connects your nasal cannula to the extension tubing.

Maybe I should rush over to the club’s hyperbaric oxygen tank. At $220 per hour, it is even pricier than the lymph treatment, true, but the chamber is so spacious that I could sit upright and work.