You don't like to hear it. I mean - who wants to hear that something is going to suck and make you feel like crap?
But feedback is a biological necessity. When you burn yourself taking something from the oven, that pain you experience is a feedback loop signaling you that something is wrong. "Don't try touching that pan without an oven mitt again or you'll pay the price."
Without feedback, you'd be a hot mess all the time. And unfortunately, you usually are, because you don't pay attention to the feedback your emotions are sending you either. Yes, feedback does not just come from physical suffering, but emotional suffering as well.
When you eat the McDonald's Big Mac, then feel like crap immediately afterward, guilty, ashamed, those emotions are sending you a biological signal that something is wrong and needs to change.
When you start working out again - you walk back into the gym for the first time in a while and step onto the treadmill, turn it on and start jogging - your body is saying "This sucks! I'd rather be sitting on the couch at home watching The Young and the Restless right now." (Is that show still on TV?!?) This is that same feedback system telling you that you need to make a change. A change where exercise is more recognized as a routine habit by your body.
Because guess what happens when exercise is reintroduced into your routine? When you don't workout for a day or two, you actually get feedback that tells you that you need to make a change! Any routinely active person can tell you that missing a workout or two makes them feel tired, weaker and just "off". But you feel like that all the time anyway!
So how do you start to take action now? Listen to the feedback signals your body is giving you. Do you feel tired at 2 pm every Monday through Friday? What did you eat up to that point? How much physical activity have you had? It's being actively conscious in these moments, then acting on them immediately - see how here - that will turn into positive and productive change that lasts.