58f workout daily with cardio and resistance training. Recently, I had a flu and then the next week a cold and not eating enough and not working out for two weeks, I had a sudden loss of muscle in my arms. At first, I thought it was my skin because now it’s floppy, but now I realize it is muscle loss. I have increased my protein intake this week and gotten back into my full routine and already feeling back to normal in strength and cardiovascular ability. To be fair, I was never as focused on upper body as lower, so I was not as strong. Maybe that’s why I lost muscle mass there. Now I am doing a lot more upper body and pushing myself in that regard. It’s fine and feels good. I have heard that at my age I may not regain lost muscle. Anybody have any words of wisdom and encouragement about building my arms back? I’m very disappointed in having these floppy arms that were not really like this only one month ago. Any recommendations for building my muscle mass back in my arms?