Cycling

Prior to receiving a diagnosis of vascular and neurogenic TOS, but for a couple of months after experiencing the first symptoms (unknown at the time) I was spending 60 minutes a day cycling on a hardtail (no suspension) hybrid (part road bike, part mountain bike) bike.

I've had a few tentative trial sessions back on the bike since my dx, but do develop pain symptoms during. It is difficult to know whether these are due to TOS or are just normal pain following a long period of inactivity.

I am seriously considering whether acquiring a recumbent bike will be not only a short-term solution, but also be better for the long-term avoidance of issues which can be provoked by riding on upright bikes (low back, upper back, elbows, wrists, neck)

Treadmill, Cross-Trainer, Stepper
Any position where my head and neck are unsupported for periods of 45m+ currently provokes pain in the neck/shoulder region, so extended periods on almost any type of cardio equipment (treadmill, x-trainer, stepper) are not practical.

Before I became aware of the unsupported head and neck trigger, I did spend quite a lot of time on a treadmill. Sometimes whilst running, I would notice numbness developing in the 4th and 5th digits of both hands (ulnar nerve symptoms)

I've also spent time on a x-trainer, but this requires considerable shoulder movement in addition to flexion at the elbow, which provokes both neck/shoulder and ulnar nerve symptoms.

Currently offering hope are recumbent stationary bikes. I've been able to spend up to 60 minutes on one of these, with the help of a dedicated head and neck support to supplement the backrest of the bike itself. This is one of the things that I wish to share a picture of, and will soon.

Versa-Climber
This is another thing I was using almost every day, for about 20-30 minutes a day prior to stopping as a preventative measure against aggravating TOS. Exercising on a Versa Climber involves repetitive overhead movements. I'm concerned that my increased use might have contributed to development of TOS, but my phyiso is skeptical about this possibility.