>>28459047
If you have no desire to begin jogging/more of normal walking then just do exactly what you're currently doing but 50% of it.

Go fast but don't give it 100%, give it 50% over a prolonged period of time so your body adapts to the extra 400ccs of displacement. Blood flow will improve in time depending how unhealthy you are or if you smoke (restricts blood flow) diet also plays a hand in things