My niece Lindsey is training young horses for the race track. Her job is to teach them manners while someone is on their backs. She rides 5 Thoroughbreds for an hour every day. Before they train for racing they have to build their stamina and strength so she rides them on the track but keeps them at 40 mph — not 50 but 40. When ready the pros take over and kick it up a notch. This is how we should work with our bodies. Not going full tilt at 50 mph but holding back until we are ready. Enthusiasm can ruin you and leave you with injury.
It doesn’t have to happen this way when you pace your self. When you start walking go for 10 minutes a day until you can do 20 or 30. If you are breathless and can’t carry on a conversation then you need to slow down. The body will adjust or bust. If you hurt yourself you may never be able to get going again. It is far better to do too little than too much.
Think also about long term goals. If you were to start by lifting 4 days a week with 6 days a week of walking or running how long do you think you could maintain? If you don’t break down and hurt yourself you may see that you need to increase your time at the gym to stay at the same weight. Be reasonable with what you are asking your body to do. Make sure you are making it work and giving it healthy fuel. It will thank you.