Get a workout buddy. Can be a friend or spouse or a trainer, but someone who will make you show up because you know they're going to be there and you'll be a jackass if you bail on them. They'll also make you look forward to the time together, and help you not think about being tired or sore or sweaty or how many left you have, whatever. I'm a trainer and my most valuable skill is making my clients forget they're working out and that they hate working out. The less you hate what you're doing, the more likely you are to do it, so find something you don't mind, and then find someone you like to do it with. Start there.

If you want to get into gym life and weight training, find a good trainer. Date around and find someone you click with. The Internet is full of good and bad advice, but a real(that means certified) trainer will have mostly good advice. If you can't afford a trainer, then stick to the machines because it's harder to hurt yourself on those. Anything is better than nothing, but be sure to take your time because moving too fast causes injuries and injuries only waste time, set you back and possibly stop you for good. Learn to enjoy the process and the journey and this will become the lifestyle change people say it should be.

Good luck and be sure to have fun!

I do something I enjoy 4 days a week, Brazilian Jiujitsu. I augment it with something I don't - strength training once a week for half an hour. One warm up set of 12 reps and one working set of 5-8 reps to complete failure. I use machines to avoid injury from failure. 5 exercises- leg press, chest press, row, lat pulldown and overhead press. It's a pretty intense workout. My goal is to keep the muscle I have and prevent injury in jiujitsu. I feel like I get like 40% of the weight training benefit for like 20% of the work that I've put in before with barbell training (strong lifts, 5/3/1, madcow, etc).

First, ask yourself is there some sport you'd really like to try. Historical European Martial Arts is longsword and sword and shield fighting, there's kendo, tai chi, tennis, a world of options. If you pick a sport you enjoy, it's not exercise, it's play.

If there isn't anything you like to do, try this program. Basically designed for desk jockeys, it's about 15 minutes a day and the only equipment you need is a timer. Starts very low key and you move up at your own pace. Royal Canadian Air Force Exercise Plan

http://www.fit450.com/HTML/5BX_chart1.html

Read "the power of habit", then use it to create healthy habits. Nobody can change his life in an instant. The book explains how to accomplish any habit in small steps.

It's not about what to do specifically, its about moving in the right direction in a healthy way

I felt the same paralysis of making decisions and figuring out the right exercises to do. So I got a personal trainer through an app and it was game changing. They would send me encouraging texts and give me some accountability and do the hard work of coming up with exercise routines for me so I didn’t have to think about it. It was pretty expensive so I switched to a cheaper app that doesn’t have 1 on 1 support and customization, now that I have some confidence in myself and my ability to do it.

The first app I used was called Future and the one I use now is called Ladder. I do weight lifting and some cardio but both apps have a variety of stuff, Future more so because the trainers can totally customize anything.

What’s your goal? Do you want to get strong? Big?

C25k. Simpleses.

Find your limit physically and work your body near that. Over time, the limit will shift. Keep shifting your exercise to match your new limit.

Just start with a small habit. Try doing one push-up per day for a week, then if you don’t skip any days, increase it to five push-ups per day.

I think it's kind of hard to exercise just for health. Athletic goals work better. Try a couch to 5k program, see how many pushups you can do & train to do more, learn to stand on your hands or try to jump higher than you can now.

If you are asking what will help maintain your body for the long run, yoga is so good. In yoga classes I see people older than me in great shape still and able to move in every direction, flexible and strong.

If you want to look better, lifting cannot be beat. Add just a little lean mass and shape, small change but big improvement in looks.

But the most important advice is to do something you actually enjoy and will keep doing. Any sort of activity is much, much better than some ambitious plan you don't actually do. Try a lot of things, and after 6 weeks of consistent exercise of any sort, you will feel enough better that it will stick. You will sleep better too.

Focus on building muscle.

Do you have a doctor? They could give you personal and accurate advice on what would help you, specifically.

It's one of those things where "work hard" isn't the wrong answer. Only hard work forces your body to build muscle.