Thr warming to avoid excessive heat with the Butran's patch (and any duragesic patch for extended pain relief) is to avoid premature "dumping" of the pain medication from the patch into your system (and a possible drug overdose). Release of the medication is on a predetermined rate in a chemical bond that is linked to normal body temperature.
I am on the fentanyl patch and a physical therapist by profession.
I think your vision that weight loss needs to be coupled with vigorous, all out, drenching in sweat exercise is misplaced. Extreme exercise need not be the expected level of activity to see effective weight loss. As a counter point, I would suggest that extreme exercise leaves you more at risk for muscle and joint damage due to overly stressing joints and muscles that are weakened and at a risk for injury due to prolonged lack of use.
Slow and steady wins the race. The affirmation holds truth and wisdom.
Walking will be your best friend in your goal to lose weight and to sustain the weight loss. No equipment necessary but a pair of quality running or walking shoes. Link up with a friend and find a walking buddy or adopt a dog to accompany you on your walks and to encourage being out and about. Your vision of high intensity cardio work outs will likely leave you sitting on the sidelines with a continuum of minor muscle and joint injuries. Walking will set you on a path for sustained success.
I am a former marathon runner. Running has been my oxygen and source of solace for most of my life. Although I can no longer run, it is my love of long distance running that gives me the resiliency to continue to stand, walk, and put one foot in front of the other. It has also given me a lean body frame that makes it easier for me to remain upright and functional. The beauty of walking is also to be found in appreciating and enjoying the beauty of nature that surrounds you. Go to a park or walk along trails in a forested area where you live. Listen to the chatter of the birds overhead and delights in watching the antics of squirrels. There is much benefit to one's mental and emotional health in walking outdoors and connecting to nature.
Best wishes to you in reclaiming of your health,
Thank you for the advice & encouragement!