44 here and I am able to workout over my lunch. I do it everyday but do different activities so I can recover. I ran a marathon in 2011 before elk hunting and I had more pep up the mountain than when I was 22.
I thnk the key is to commit to doing it as part of you regular schedule. I almost always look forward to my workouts but even when I don't I'm happy I completed them when I leave the gym. If you are new get help from a trainer. If your motivation is gone sign up for a class as you'll build relationships that will help hold you accountable. Pretty soon you'll feel so good you won't want to stop.
